HomeMy WebLinkAbout3.3Item 3.3
TOWN OF LOS ALTOS HILLS June 2, 2011
Staff Report to the Planning Commission
RE: INITIAL STUDY AND MITIGATED NEGATIVE DECLARATION FOR THE
BARRON CREEK RESTORATION/MAINTENANCE PROJECT; #83-11-MISC.
FROM: Cynthia Richardson, Consulting Planner
APPROVED BY: Debbie Pedro, AICP, Planning Directn;)p
RECOMMENDATION
That the Planning Commission:
Review, make comments, and forward a recommendation that, based on the Initial
Study, the City Council adopt the Mitigated Negative Declaration and Mitigation
Monitoring Program in Attachments 1, 2 and 3; and
2. Forward a recommendation that the City Council approve the requested maintenance
project, based on the environmental document and subject to the mitigation measures
as shown in the Initial Study.
DISCRETIONARY ACTIONS
The following discretionary actions by the City Council are required for approval of the
project:
1. Adoption of the Mitigated Negative Declaration and Mitigation Monitoring Program
2. Approval of the Maintenance Improvement project.
The Planning Commission's actions are recommendations to the City Council.
PROJECT REVIEW
Barron Creek is one of the major creeks that flow through the Town of Los Altos Hills.
Maintaining the creek corridor is important to the proper flow if the creek. Currently
nineteen Willow trees located within the bed of the creek collect debris and -block the
normal flow of water within the creek. The creek has also become full of weeds and silt
which also obstructs the flow of water. This maintenance project and the removal of the
Willow, trees require approval from the Unites States Army Corps of Engineers
(USACE), Regional Water Quality Board (RWQB) and the California Department of
Fish and Game (CDFG) once the California Environmental Quality Act (CEQA)
document is approved. CEQA requires analysis of impacts to the area based on the
proposed project. A Biological Evaluation was prepared by Live Oak Associates dated
Barron Creek Annual Maintenance
June 2, 2011
Page 2 of 3
April 13, 2011 (Attachment #4) the information was used to evaluate biological concerns
stemming from the project.
PROJECT DESCRIPTION
The proposed project is for annual maintenance of a segment of Barron Creek located on
the south side of West Fremont Road in a storm drain easement along west and south
property lines of 26170 West Fremont Road. This portion of the creek is currently
overgrown with non-native, invasive vegetation in its downstream half, and debris has
accumulated at the base of several willows located within the channel bed at the upstream
end, obstructing the flow of water through the channel. To keep the channel clear of
debris and to maintain an unobstructed flow of water, the Town is proposing to clear out
weeds growing within the channel on an annual basis and remove up to nineteen willows
located within the channel bed at the upstream end of the site. The portion of the channel
around the willows will be temporarily dewatered via a cofferdam to allow for their
removal. Willow pole cuttings will be installed along the channel banks to mitigate for
the removal of the willows. A revegetation plan has been prepared by Live Oak
Associates see Attachment # 5.
ENVIRONMENTAL REVIEW
In compliance with the California Environmental Quality Act (CEQA), an Initial Study
(Attachment #1), Mitigated Negative Declaration (Attachment #2) and Mitigation
Monitoring Program (Attachment #3) have been prepared for the project. The review
period for the Negative Declaration will end on June 16, 2011. The Planning Commission
may comment on both the Mitigated Negative Declaration and the maintenance project.
The Mitigated Negative Declaration must be adopted by the City Council before
approving the project. In order to recommend adoption, the Commission must find that
all potential significant environmental effects are addressed through the proposed
mitigation measures.
CONCLUSIONS
Based on -the Initial Study, staff has concluded that the proposed maintenance project, as
mitigated, will not have a significant effect on the environment. The. Negative
Declaration identifies specific mitigation measures and establishes a Mitigation
Monitoring Program_ to address the potentially significant environmental impacts
identified in the Initial Study.
Staff has concluded that the proposed maintenance project is in compliance with the
General Plan and Zoning Ordinance, and would allow the project to occur.
Barron Creek Annual Maintenance
June 2, 2011
Page 3 of 3
ATTACHMENTS
1. Initial Study and Mitigation Monitoring Plan
2. Mitigated Negative Declaration
3. Barron Creek Biological Evaluation prepared by Live Oak Associates dated April
13, 2011.
Attachment 1
INITIAL STUDY
Initial Study Checklist & References
Barron Creek Annual Maintenance 2011
Project #83'7.11.Misc..., ,.,:...
Town of IROS Altos Hills=Planning Department
26379 Fremont Road
Los Altos Hills, CA 94022
Town of Los Altos Hills
Initial Study Barron Creek Annual Maintenance
June 16, 2011
Page 2 of 29
In accordance with the policies regarding implementation of the California
Environmental Quality Act of 1970, this document, combined with the attached
supporting data, constitutes the initial study on the subject project. This initial study
provides the basis for the determination of whether the project may have a significant
effect on the environment. If it is determined that the project may have a significant
effect on the environment, an environmental impact report will be prepared which
focuses on the area of concern identified --by this .initial study. If it is determined that the
project would not have a significant effect on the environment, it is eligible for a
Negative Declaration. If it is determined that the proposed project could have a
significant effect on the environment, however, the significant effects of the project have
been reduced to a less -than -significant level because revisions in the project have. been
made by or agreed to be the project applicant, then the project would be eligible for a
Mitigated Negative Declaration.
Environmental Checklist Form
1. Project Title: Barron Creek Annual Maintenance
2. Lead Agency Name and Address: Town of Los Altos_ Hills, 26379 Fremont Road,
. Los Altos Hills, California 94022
3. Contact Person and Phone Number: Debbie Pedro, AICP, Planning Director
(650) 941-7222
4. Initial Study prepared by: Cynthia Richardson, Consulting Planner
(650) 941-7222
5. Project Location: The project site is located on the south side of West Fremont
Road in a drainage easement along the property line of 26170 West Fremont Road,
Los Altos Hills, CA 94022, APN# 175-35-036.
6. Project Sponsor's Name and Address: Town of Los Altos Hills, 26379 Fremont
Road, Los Altos Hills, California 94022
7. General Plan Designation: R -Residential
S. Zoning: R -A (Residential -Agricultural)
9. Description of Project: The proposed project is for annual maintenance of the
aforementioned reach of Barron Creek. This reach of the creek is currently
overgrown with non-native, invasive vegetation in its downstream half, and debris
has accumulated at the base of several willows located within the channel bed at the
upstream end, obstructing the flow of water through the channel. To keep the
channel clear of debris and maintain an unobstructed flow of water, the Town is
proposing to clear out weeds growing within the channel on an annual basis and
remove up to nineteen willows located within the channel bed at the upstream end
of the site. The portion o f the channel around the willows will be temporarily
Town of Los Altos Hills
Initial Study Barron Creek Annual Maintenance
June 16, 2011
Page 3 of 29
dewatered via a cofferdam to allow for their removal. Willow pole cuttings will be
installed along the channel banks to mitigate for the removal of the willows.
10. Surrounding Land Uses and Setting: The project is located on the south side of
West Fremont Road and along the western property line of 26170 West Fremont
Road. Surrounding land uses include one and two story single-family residences
with minimum lot size -of 1 acre.
11. Other public agencies whose approval is required: United States Army Corps of
Engineers (USACE), Department of Fish and Game (CDFG), Regional Water
Quality Board (RWQB).
Town of Los Altos Hills
Initial Study Barron Creek Annual Maintenance
June 16, 2011
Page 4 of 29
ENVIRONMENTAL FACTORS POTENTIALLY AFFECTED:
The environmental factors checked below would be potentially affected by this project, involving
at least one impact that is a "Potentially Significant
Impact" as indicated by the checklist on the
following pages.
❑ Aesthetics
❑
Agriculture Resources ❑
Air Quality
Biological Resources
❑
Cultural Resources ❑
Geology /Soils
❑ Hazards & Hazardous
Hydrology / Water Quality ❑
Land Use / Planning
Materials
❑ Mineral Resources
❑
Noise ❑
Population / Housing
❑ Public Services
❑
Recreation ❑
Transportation/Traffic
❑ Utilities / Service Systems
❑
Mandatory Findings of Significance
This Initial study has been prepared in accordance with the California Environmental Quality Act.
Information and conclusions in the Initial Study are based upon staff research and the Town's General
Plan and Municipal Code.
DETERMINATION
On the basis of this initial evaluation:
I find that the proposed project COULD NOT have a significant effect on the environment, ❑
and a NEGATIVE DECLARATION will be prepared.
I find that although the proposed project could have a significant effect on the environment, Q
there will not be a significant effect in this case because the mitigation measures described on
attached sheet have been added to the project. A NEGATIVE DECLARATION will be prepared.
I find that the proposed project MAY have a significant effect on the environment, ❑
and an ENVIRONMENTAL IMPACT REPORT is required.
I find that the proposed project MAY have a significant effect(s) on the environment, but at ❑
least one effect 1) has been adequately analyzed in an earlier document pursuant to applicable
legal standards, and 2) has been addressed by mitigation measures based on the earlier analysis as
described on attached sheets, if the effect is a "potentially significant impact" or "potentially
significant unless mitigated." An ENVIRONMENTAL IMPACT REPORT is required, but it must
analyze only the effects that remain to be addressed.
I find that although the proposed project could have a significant effect on the environment, there ❑
WILL NOT be a significant effect in this case because all potentially significant effects (a) have been
analyzed adequately in an earlier EIR pursuant to applicable standards and (b) have been avoided or
mitigated pursuant to that earlier EIR, including revisions or mitigation measures that are imposed upon the
proposed project.
Signature: Date: June 16, 2011
Debbie Pedro, AICP, Planning Director
Town of Los Altos Hills
Initial Study Barron Creek Annual Maintenance
June. 16, 2011
Page 5 of 29
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I. AESTHETICS. -- Would. the project:
a) Have a substantial adverse effect on a ❑ ❑ ❑ Q
scenic vista?
b) Substantially damage scenic resources,
including, but not limited to, trees, rock ❑ ❑ ❑ Q
outcroppings, and historic buildings within
a state scenic highway?
c) Substantially degrade the existing visual ❑ ❑ Q ❑
character or quality of the site and its
surroundings?
d) Create a new source of substantial light ❑ ❑ ❑ Q
or glare which would adversely affect day
or nighttime views in the area?
DISCUSSION:
The proposed project is situated along side property lines, adjacent to five properties which maintain single
family residences. The Los Altos Hills General Plan identifies important vistas, historic sites, and scenic
highways within the Town. None of these resources listed in the General Plan will be significantly
impacted by the proposal.
Aesthetic impacts due to the annual maintenance of the creek channel and tree removal will be limited to
the immediate area. The removal and replacement of the nineteen willow trees will have some visual
impact to the adjacent neighbors opening up views between properties. The impact will be temporary until
the newly planted replacement trees are mature. Therefore there is little or no long term visual impact.
MITIGATION:
Aesthetic Measure 1: A revegetation plan will be prepared and implemented to compensate for the loss of
the nineteen willow trees. A minimum 1:1 replacement -to -removal ratio along the upper banks of the same
reach of the creek where the willows are being removed is required. Willow pole cuttings will be installed
along the channel banks to mitigate for the removal of the willows. This measure will reduce impacts to a
less -than -significant level.
Sources:
1,5,6
Town of Los Altos Hills
Initial Study Barron Creek Annual Maintenance
June 16, 2011
Page 6 of 29
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II. AGRICULTURE RESOURCES—
Would the project:
a) Convert Prime Farmland, Unique
Farmland, or Farmland of Statewide
Importance (Farmland), as shown on the Ll Ll❑ Q
maps prepared pursuant to the Farmland
Mapping and Monitoring Program of the
California Resources Agency, to non-
agricultural use?
b) . Conflict with existing zoning for ❑ ❑ ❑ Q
agricultural use, or a Williamson Act
contract?
c) Involve other changes in the existing
environment which, due to their location or ❑ ❑ ❑ Q
nature, could result in conversion of
Farmland, to non-agricultural use?
DISCUSSION:
The proposed project will have no foreseeable impact on Agricultural Resources. The site is not used as
agricultural land.
MITIGATION:
None
Source:
8
Town of Los Altos Hills
Initial Study Barron Creek Annual Maintenance
June 16, 2011
Page 7 of 29
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substantially to an existing or projected air
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quality violation?
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increase of any criteria pollutant for which the
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standard (including releasing emissions which
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exceed quantitative thresholds for ozone
t^3'
precursors)?
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pollutant concentrations?
III. AIR QUALITY -- Would the project:
a) Conflict with or obstruct implementation of
❑ ❑ ❑
Q
the applicable air quality plan?
b) Violate any air quality standard or contribute
substantially to an existing or projected air
❑ ❑ ❑
Q
quality violation?
c) Result in a cumulatively considerable net
increase of any criteria pollutant for which the
project region is non -attainment under an
applicable federal or state ambient air quality
❑ ❑ ❑
Q
standard (including releasing emissions which
exceed quantitative thresholds for ozone
precursors)?
d) Expose sensitive receptors to substantial
pollutant concentrations?
❑ ❑ ❑
Q
e) Create objectionable odors affecting a
❑ ❑ ❑
Q
substantial number of people?
DISCUSSION:
Santa Clara County is currently a non -attainment basin
for ozone thresholds but achieves an attainment level
for carbon monoxide emissions. The proposed project will not increase any emissions or contribute to
substantial pollutant concentrations.
MITIGATION:
None
Source:
9
Town of Los Altos Hills
Initial Study Barron Creek Annual Maintenance
June 16, 2011
Page 8 of 29
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any species identified as a candidate,
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riparian habitat or other sensitive natural
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IV. BIOLOGICAL RESOURCES --
Would the project:
a) Have a substantial adverse effect, either
directly or through habitat modifications, on
any species identified as a candidate,
❑
Q
❑
❑
sensitive, or special status species in local or
regional plans, policies, or regulations, or by
the California Department of Fish and Game
or U.S. Fish and Wildlife Service?
b) Have a substantial adverse effect on any
riparian habitat or other sensitive natural
community identified in local or regional
❑
Q
❑
❑
plans, policies, regulations or by the
California Department of Fish and Game or
US Fish and Wildlife Service?
c) Have a substantial adverse effect on
federally protected wetlands as defined by
Section 404 of the Clean Water Act
❑
Q
❑
❑
(including, but not limited to, marsh, vernal
pool, coastal, etc.) through direct removal,
filling, hydrological interruption, or other
means?
d) Interfere substantially with the movement
of any native resident or migratory fish or
wildlife species or with established native
❑
Q
❑
❑
resident or migratory wildlife corridors, or
impede the use of native wildlife nursery
sites?
e) Conflict with any local policies or
ordinances protecting biological resources,
❑
❑
Q
❑
such as a tree preservation policy or
ordinance?
f) Conflict with the provisions of an adopted
Habitat Conservation Plan, Natural ❑ ❑ Q ❑
Community Conservation Plan, or other
approved local, regional, or state habitat
conservation plan?
DISCUSSION:
A Biological Evaluation was prepared by Live Oak Associates dated April 13, 2011. The report
specifically covers the area of Barron Creek off of West Fremont Road, across from Donelson Place, in the
Town of Los Altos Hills, Santa Clara County, California. The creek runs within an easement located along
the residential property line at 26170 West Fremont Road. The project is for annual maintenance of
Town of Los Altos Hills
Initial Study Barron Creek Annual Maintenance
June 16, 2011
Page 9 of 29
approximately 624 linear feet of Barron Creek to keep the creek clear of weeds and debris and to maintain
an unobstructed flow of water through the channel. The project also includes the removal of up to nineteen
willows at the upstream end of the onsite channel and hand removal of weeds. Willow pole cuttings will be
installed along the channel banks to mitigate for the removal of the willows. This project would have no
effect on regional populations of special status plant species since the site provides no habitat for special
status plans.
A formal wetland delineation of the site was completed in August 2010. The USACE issued their
jurisdictional determination in March 2011 at which time they claimed jurisdiction over the reach of the
creek occurring onsite. The creek is also subject to the jurisdiction of the CDFG up to the top of bank or
the edge of the associated riparian vegetation, whichever is greater.
Several special status animal species occur, or once occurred, regionally. Proposed channel maintenance
activities would have no effect on these species or their breeding success because there is little or no
likelihood that they are present in the area with the exception of the yellow warbler. Yellow warblers may
utilize the site for nesting. This project may result in the temporary loss of foraging or nesting habitat for
this species but would be considered less than significant.
The willows on the site and surrounding trees provide potential nesting habitat for tree -nesting raptors and
other migratory birds. The maintenance activities could result in the abandonment of active nests or direct
mortality to these birds. This may be considered a significant impact and mitigation measures have been
provided.
The project occurs within jurisdictional waters governed by the United States Army Corps of Engineers
(USACE) and subject to Regional Water Quality Control Board (RWQB) and the California Department of
Fish and Game (CDFG) regulations. The removal of the nineteen willow trees within the channel bed will
result in temporary disturbance to approximately 175 linear feet of waters of the U.S. Vegetation is
expected to naturally recruit from surrounding areas to cover the areas left barren; however the removal of
the willow trees would be considered a significant impact and will require mitigation.
MITIGATION:
Biologic Measure 1: Trees planned for removal should be removed during the non -breeding season
(September 1 through January 31). If it is not possible to avoid tree removal during the breeding season
(February 1 through August 31), a qualified biologist should conduct a pre -disturbance survey for tree -
nesting raptors and migratory birds in all trees planned for removal and immediately adjacent to the
disturbance zone no more than 30 days from the onset. of the removal activities, if such disturbance will
occur during the breeding season. If nesting raptors and migratory birds are detected on the site during the
survey, a suitable activity -free buffer should be established around all active nests. The precise dimension
of the buffer (up to 250 .feet) would be determined at that time and may vary depending on location and
species. Buffers should remain in place for the duration of the breeding season or until it has been
confirmed by a qualified biologist that all chicks have fledged and are independent of their parents: Pre -
disturbance surveys during the non -breeding season are not necessary for tree -nesting raptors and migratory
birds, as they are expected to abandon their roosts during disturbance activities. Implementation of the
above measures would mitigate impacts to tree -nesting raptors and migratory birds to a less -than -
significant level.
Biologic Measure 2: A revegetation plan will be prepared to compensate for the loss of the nineteen
willow trees. A minimum 1:1 replacement -to -removal ratio along the upper banks of the same reach of the
creek where the willows are being removed is required. The portion of the channel around the willows will
be temporarily dewatered via a cofferdam to allow for their removal. Willow pole cuttings will be installed
along the channel banks to mitigate for the removal of the willows. This measure will reduce impacts to a
less -than -significant level.
Town of Los Altos Hills
Initial Study Barron Creek Annual Maintenance
June 16, 2011
Page 10 of 29
Sources:
1,5,6,10,17,18,19
Town of Los Altos Hills
Initial Study Barron Creek Annual Maintenance
June 16, 20.11
Page 11 of 29
V. CULTURAL RESOURCES —
Would the project:
a) Cause a substantial adverse change in the
significance of a historical resource as defined ❑ ❑ ❑ Q
in ' 15064.5?
b) Cause a substantial, adverse change in the
significance of an archaeological resource ❑ ❑ ❑ Q
pursuant to '15064.5?
c) Directly or indirectly destroy a unique
paleontological resource or site or unique ❑ ❑ ❑ Q
geologic feature?
d) Disturb any human remains, including ❑ ❑ ❑ Q
those interred outside of formal cemeteries?
DISCUSSION:
The proposed Barron Creek maintenance project will have no foreseeable impact on Cultural Resources as
defined in Title 14; Chapter 3; Article 5; Section 15064.5 of the California Environmental Quality Act. The
site does not contain a listed historical building and no known archeological resources exist on the subject
property.
However, if any artifacts or human remains are discovered, work in the vicinity of the find shall stop
immediately until a qualified archaeologist can evaluate the site and determine the significance of the find
per the mitigation measure described below.
MITIGATION:
Cultural Measure 1: Upon discovering or unearthing any possible burial site as evidenced by human
skeletal remains or artifacts, the person making such discovery shall immediately notify the County of
Santa Clara Coroner and no further disturbance of the site may be made except as authorized by the County
Coordinator of Indian Affairs.
Sources:
3,5,16
Less Than
4XVz
°:
Less>Than
LPotentially
k r t
Significant with
4
S�gmficant�
Significant;
No Impact
rI4
1Vnlctto�grato�roan
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io�n �
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5
V. CULTURAL RESOURCES —
Would the project:
a) Cause a substantial adverse change in the
significance of a historical resource as defined ❑ ❑ ❑ Q
in ' 15064.5?
b) Cause a substantial, adverse change in the
significance of an archaeological resource ❑ ❑ ❑ Q
pursuant to '15064.5?
c) Directly or indirectly destroy a unique
paleontological resource or site or unique ❑ ❑ ❑ Q
geologic feature?
d) Disturb any human remains, including ❑ ❑ ❑ Q
those interred outside of formal cemeteries?
DISCUSSION:
The proposed Barron Creek maintenance project will have no foreseeable impact on Cultural Resources as
defined in Title 14; Chapter 3; Article 5; Section 15064.5 of the California Environmental Quality Act. The
site does not contain a listed historical building and no known archeological resources exist on the subject
property.
However, if any artifacts or human remains are discovered, work in the vicinity of the find shall stop
immediately until a qualified archaeologist can evaluate the site and determine the significance of the find
per the mitigation measure described below.
MITIGATION:
Cultural Measure 1: Upon discovering or unearthing any possible burial site as evidenced by human
skeletal remains or artifacts, the person making such discovery shall immediately notify the County of
Santa Clara Coroner and no further disturbance of the site may be made except as authorized by the County
Coordinator of Indian Affairs.
Sources:
3,5,16
Town of Los Altos Hills
Initial Study Barron Creek Annual Maintenance
June 16, 2011
Page 12 of 29
VI. GEOLOGY AND SOILS -- Would the project:
a) Expose people or structures to potential
®
❑
❑
Q
substantial adverse effects, including the risk
of loss, injury, or death involving:
Potentially
6Less'Than
#
Less Thant'
1 ;
i) Rupture of a known earthquake fault, as
Significant with
r
delineated on the most recent Alquist-Priolo
Significant'
Significant
No Impact
Earthquake Fault Zoning Map issued by the
a
Ming t►on
r
Impact
s r
State Geologist for the area or based on other
❑
Incorporation
❑
Q
substantial evidence of a known fault? Refer
to Division of Mines and Geology Special
VI. GEOLOGY AND SOILS -- Would the project:
a) Expose people or structures to potential
®
❑
❑
Q
substantial adverse effects, including the risk
of loss, injury, or death involving:
i) Rupture of a known earthquake fault, as
delineated on the most recent Alquist-Priolo
Earthquake Fault Zoning Map issued by the
State Geologist for the area or based on other
❑
❑
❑
Q
substantial evidence of a known fault? Refer
to Division of Mines and Geology Special
Publication 42.
ii) Strong seismic ground shaking?
❑
❑
❑
Q
iii) Seismic -related ground failure, including
❑
❑
❑
Q
liquefaction?
iv) Landslides?
❑
❑
❑
Q
b) Result in substantial soil erosion or the loss
of topsoil?
❑
❑
❑
Q
c) Be located on a geologic unit or soil that is
unstable, or that would become unstable as a
result of the project, and potentially result in
❑
❑
❑
Q
on- or off-site landslide, lateral spreading,
subsidence, liquefaction or collapse?
d) Be located on expansive soil, as defined in
Table 18-1-B of the Uniform Building Code
(1994), creating substantial risks to life or
❑
❑
❑
Q
property?
e) Have soils incapable of adequately
supporting the use of septic tanks or
alternative waste water disposal systems
❑
❑
❑
Q
where sewers are not available for the disposal
of waste water?
DISCUSSION:
No fault trace exists within the vicinity of the proposed project.
MITIGATION:
None
Sources:
12, 17,18
Town of Los Altos Hills
Initial Study Barron Creek Annual Maintenance
June 16, 2011
Page 13 of 29
VII. HAZARDS AND HAZARDOUS MATERIALS --
Would the project:
a) Create a significant hazard to the public or ❑ ❑ ❑ Q
the environment through the routine transport,
use, or disposal of hazardous materials?
b) Create a significant hazard to the public or
the environment through reasonably
foreseeable upset and accident conditions ❑ ❑ ❑ Q
involving the release of hazardous materials
into the environment?
c) Emit hazardous emissions or handle
i'Vf
3 b -� 'k
SWC
-(.: ik rz, 4
Yr �''IL.E y�'.�"v `vcs -+s.
.pin �*Ytik5 i5 �"PA'
'' `� 'i"` 4�
S.t�
b*vr'7k3 �'"°M
s
Sriy""L6iS:i�}�
"C,4 ., fY 3
❑
-�,x x,
r s S - s 3
z �,
f �'�� � ,� x � �k� �,��� �� ���� �� � ,�t 4 t
ft w xk "€
�Potent►all�� g �,�
-�.'Y`L
Less Than
�� � �
is tom£`•
„ _a
# k
of an existing or proposed school?
n�#icant
Significant Wirth
�
rt'
S�gmficant:
No�Impact `�$
d) Be located on a site which is included on a
Impact
HIM
�rt��at�on
�
x x
x ,Impact
pursuant to Government Code Section
d:
❑
❑
Q
65962.5 and, as a result, would it create a
f
E
significant hazard to the public or the
VII. HAZARDS AND HAZARDOUS MATERIALS --
Would the project:
a) Create a significant hazard to the public or ❑ ❑ ❑ Q
the environment through the routine transport,
use, or disposal of hazardous materials?
b) Create a significant hazard to the public or
the environment through reasonably
foreseeable upset and accident conditions ❑ ❑ ❑ Q
involving the release of hazardous materials
into the environment?
c) Emit hazardous emissions or handle
hazardous or acutely hazardous materials,
❑
❑
❑
Q
substances, or waste within one-quarter mile
of an existing or proposed school?
d) Be located on a site which is included on a
list of hazardous materials sites compiled
pursuant to Government Code Section
❑
❑
❑
Q
65962.5 and, as a result, would it create a
significant hazard to the public or the
environment?
e) For a project located within an airport land
use plan or, where such a plan has not been
adopted, within two miles of a public airport
❑
❑
❑
Q
or public use airport, would the project result
in a safety hazard for people residing or
working in the project area?
f) For a project within the vicinity of a private
airstrip, would the project result in a safety
❑
❑
❑
Q
hazard for people residing or working in the
project area?
g) Impair implementation of or physically
interfere with an adopted emergency response
❑
❑
❑
Q
plan or emergency evacuation plan?
h) Expose people or structures to a significant
risk of loss, injury or death involving wildland
fires, including where wildlands are adjacent
❑
❑
❑
Q
to urbanized areas or where residences are
intermixed with wildlands?
DISCUSSION:
The proposed maintenance project does not produce a hazard or hazardous waste and will have no
foreseeable impact related to Hazards and Hazardous Materials. The site is not located in an identified
location according to CA Government Code 65962.5.
Town of Los Altos Hills
Initial Study Barron Creek Annual Maintenance
June 16, 2011
Page 14 of 29
MITIGATION:
None
Sources:
13
Town of Los Altos Hills
Initial Study Barron Creek Annual Maintenance
June 16, 2011
Page 15 of 29
VIH HYDROLOGY AND WATER QUALITY --
: .,4 H"
t k ivY'al+-F`
C:•� .cf iF3 S ?�- '['4Y�'S1�3++rt. },,F�''»$»
+
i
5 J'
c rLessThanfi,
4 # $d+2'�
?
❑ Q
discharge requirements?
s r
art
Potentially
igmficant hky
it
Less)Thafi
t
z $4
S�gmficant r
S�gnilicant
No Impact=
M4
Impact
M►hgat�on A
Impact
,
r F '
a
Incorporation
❑
❑
❑ Q
existing nearby wells would drop to a level
�h
fi.9M"?'i:=
Ky
planned uses for which permits have been
X .-':Zf,.1 .c <_Tf.k.vik". .m .5}._„�",.,Tni •1'
tt Ai
af.
,n$;M r.n:�Ni .,.. wki._ 1.,.`�y`*,,Y&�..'sv+sS�3Y::.�.£,-Y
granted)?
VIH HYDROLOGY AND WATER QUALITY --
Would the project:
a) Violate any water quality standards or waste
❑
❑
❑ Q
discharge requirements?
b) Substantially deplete groundwater supplies or
interfere substantially with groundwater recharge
such that there would be a net deficit in aquifer
volume or a lowering of the local groundwater
table level (e.g., the production rate of pre-
❑
❑
❑ Q
existing nearby wells would drop to a level
which would not support existing land uses or
planned uses for which permits have been
granted)?
c) Substantially alter the existing drainage
pattern of the site or area, including through the
alteration of the course of a stream or river, in a
❑
❑
Q ❑
manner which would result in substantial erosion
or siltation on- or off-site?
d) Substantially alter the existing drainage
pattern of the site or area,. including through the
alteration of the course of a stream or river, or
❑
❑
Q ❑
substantially increase the rate or amount of
surface runoff in a manner which would result in
flooding on- or off-site?
e) Create or contribute runoff water which would
exceed the capacity of existing or planned
❑
❑
❑ Q
stormwater drainage systems or provide
substantial additional sources of polluted runoff?
f) Otherwise substantially degrade water quality?
❑
❑
❑ Q
g) Place housing within a 100 -year flood hazard
area as mapped on a federal Flood Hazard
❑
❑
❑ Q
Boundary or Flood Insurance Rate Map or other
flood hazard delineation map?
h) Place within a 100 -year flood hazard area
structures which would impede or redirect flood
❑
❑
❑ Q
flows?
i) Expose people or structures to a significant
risk of loss, injury or death involving flooding,
❑
❑
❑ Q
including flooding as a result of the failure of a
levee or dam?
j) Inundation by seiche, tsunami, or mudflow?
❑
❑
❑ Q
Town of Los Altos Hills
Initial Study Barron Creek Annual Maintenance
June 16, 2011
Page 16 of 29
DISCUSSION:
The proposed project will have little or no impact on Hydrology and Water Quality as defined in this
section. The existing flow patterns will not be altered by this project. Annual maintenance of the creek will
allow for better and unobstructed flows of existing drainage water. The portion of the channel around the
willows will be temporarily dewatered via a cofferdam to allow for their removal. The applicant will comply
with all state and federal regulations related to work that will impact jurisdictional waters occurring on the site.
MITIGATION:
None
Sources:
11, 14, 17,18,19
Town of Los Altos Hills
Initial Study Barron Creek Annual Maintenance
June 16, 2011
Page 17 of 29
IX.'LAND USE AND PLANNING --
Would the project:
a) Physically divide an established
community? ❑ ❑ ❑ Q
b) Conflict with any applicable land use plan,
policy, or regulation of an agency with
jurisdiction over the project (including, but
not limited to the general plan, specific plan, ❑ ❑ ❑ Q
local coastal program, or zoning ordinance)
adopted for the purpose of avoiding or
mitigating an environmental effect?
c) Conflict with any applicable habitat
conservation plan or natural community ❑ ❑ ❑ Q
conservation plan?
DISCUSSION:
The project complies with the Los Altos Hills General Plan and all applicable Town Ordinances.
MITIGATION:
None
Sources:
4,5,6
utb -
fy qi 'k
d.
%
°.I
.'��i
b�C
5,
r tier F,
r Potentially
HE
„,
ant�vtth
�.ess ThanrY
,,.0016
c
rE�
u h r
sI�hgat�o
Sig nIlcanfS�gmfil
g
r
s Significant E
No Impact ,�� 5
rg}�
��"t �. ..,.�.... � ar,i„L�, r��`i,,., k3•. .a_,t_
� ;�,w'�.��n €'.,3'=.��sR N',
4s�.`,'a`=
IX.'LAND USE AND PLANNING --
Would the project:
a) Physically divide an established
community? ❑ ❑ ❑ Q
b) Conflict with any applicable land use plan,
policy, or regulation of an agency with
jurisdiction over the project (including, but
not limited to the general plan, specific plan, ❑ ❑ ❑ Q
local coastal program, or zoning ordinance)
adopted for the purpose of avoiding or
mitigating an environmental effect?
c) Conflict with any applicable habitat
conservation plan or natural community ❑ ❑ ❑ Q
conservation plan?
DISCUSSION:
The project complies with the Los Altos Hills General Plan and all applicable Town Ordinances.
MITIGATION:
None
Sources:
4,5,6
Town of Los Altos Hills
Initial Study Barron Creek Annual Maintenance
June 16, 2011
Page 18 of 29
"y } '7" dg's " xp'•-`4 i . «filo i 'C, (,.� fgflF„`_,` ;?`-'�'3'zy' `SR 'P
'#.,X '..L.. �.. i n •z.'^`` # •E .i
1,YSy F ',c. �. ;
t-Cq;.
.*r �.i%t;s " '
f. -'a �
<�*.,}n
Ri fi `ty
a'
�Y„
��� P��� *�$,°t 'yc Y� � vk �y, ' �'�R #�fi�.�. § ��`'•'.�S''
.»
P'+sf.�tay�#` �k'�t#� �'e'?1:1
p'Kar'.4 'E �v"'_x �,j°`5��
��,C{:.`z..� ��r'iC,�,
Sa `E•... at- ss���' �f-,4
� � ,� P ��� x , � � „�� �� �� � s
� ,
�� :�,. •._e� �.��� �
`�„�,��
ess�T�#�'�"'b
Lhany���
s '1��'rt.
�. � .� �� _ 4�-�,;
.=i • k # �4 S � `a- `2t '`T�.34' ��f "` �e c'
KnPotentiall �
*a$. sysan�',`iP`,�'? �� `i 4 t
�gn�ficant#'..
cant with 4
,ia iw*<+ -2..� F
<Si ntfc
gqx
� 1-'t° 3
p m
M ngation _
Tmpacl����
z z <k
ncorporation�
re.
.? F4�..'`� Yii.€n "2E(s�..�'3 `� €x .`F`'xz
.e�3t'5.,,�3` .. �i.y
;�-• i§"hf'j�,},y.' _.sa-$4
�
f
:3`t AY'L�4i.,.iC
'r
X. MINERAL RESOURCES --
Would the project:
a) Result in the loss of availability of a known
mineral resource that would be of value to the ❑ ❑ ❑ Q
region and the residents of the state?
b) Result in the loss of availability of a
locally -important mineral resource recovery ❑ ❑ ❑ Q
site delineated on a local general plan, specific
plan or other land use plan?
DISCUSSION:
The proposed maintenance project will not result in a loss of mineral resources. The project is not located
in an area known for valued minerals.
MITIGATION:
None
Sources:
5,6,17
Town of Los Altos Hills
Initial Study Barron Creek Annual Maintenance
June 16, 2011
Page 19 of 29
Fi11's.ia13'Sili
i S }h 'f4i
�+
Y4 . #-." ��'*.Pj
-+nu'k
"-�' d`l},kE, I
iy ",!a 1.
•%2, Y;'.a d4T
J t #4 '. 4
h F
sc�i3§" r lyf riyE £-1'f " L if ``t
R,
43�
3 +�X£ f F #
k
a#
..1`'
,qY
:. qT 3
Y F
M-
L
Than
t r ,w
, .�: "z
Potentially
46
Less
z ,
r R �f
k Si nificantwith
excessive groundborne vibration or
❑
❑
Sigmficant
Impacf X
b3 'SIgn�ficant
Impact h
IYI�t� anon r
X
Tmpat
t
b, ,
r rn 'ap f
�, t ofimrd`'v�4
s, ncouporation $°
v {
h
>
fr
❑
Q
❑
above levels existing without the project?
XI. NOISE --Would the project result in:
a) Exposure of persons to or generation of
noise levels in excess of standards established
❑
❑
Q
❑
in the local general plan or noise ordinance, or
applicable standards of other agencies?
b) Exposure of persons to or generation of
excessive groundborne vibration or
❑
❑
Q
❑
groundborne noise levels?
c) A substantial permanent increase in
ambient noise levels in the project vicinity
❑
❑
Q
❑
above levels existing without the project?
d) A substantial temporary or periodic
increase in ambient noise levels in the project
❑
❑
Q
❑
vicinity above levels existing without the
proj ect?
e) For a project located within an airport land
use plan or, where such a plan has not been
adopted, within two miles of a public airport
❑
❑
❑
Q
or public use airport, would the project expose
people residing or working in the project area
to excessive noise levels?
f) For a project within the vicinity of a private
airstrip, would the project expose people
❑
❑
❑
Q
residing or working in the project area to
excessive noise levels?
DISCUSSION:
The proposed project will have temporary noise generating exposures within the adjacent neighborhood.
Small tractor equipment will be used to clean the creek bed and used for removal of the eleven willow
trees.
MITIGATION:
Noise Measure 1: Noise generating construction activities shall be limited to Monday through Saturday
between the hours of 8:00 am and 5:30 pm. No heavy noise generating equipment is allowed to be used on
Saturdays and no construction is allowed on Sundays or holidays as noted per Chapter 7, Sec.5-7-01 of the
Los Altos Hills Municipal Code.
Sources:
5, 6,
Town of Los Altos Hills
Initial Study Barron Creek Annual Maintenance
June 16, 2011
Page 20 of 29
XII. POPULATION AND HOUSING --
Would the project:
a) Induce substantial population growth in an
area, either directly (for example, by
proposing new homes and businesses) or ❑ ❑ ❑ Q
indirectly (for example, through extension of
roads or other infrastructure)?
b) Displace substantial numbers of existing
housing, necessitating the construction of ❑ ❑ ❑ Q
replacement housing elsewhere?
c) Displace substantial numbers of people,
necessitating the construction of replacement ❑ ❑ ❑ Q
housing elsewhere?
DISCUSSION:
The proposed project will not have a significant impact on population or housing.
MITIGATION:
None
Sources:
3,5
�
`y4h4 �:r
'
Less Than
��
"Po�entiahy
�
Less Than•
+
Sign►ficant with s
t r �TM,
S► n�ficant
M►pgation
5igmficant
No Impaet`
Impact
s
i
Impact41,
, ' t
'zj S y�:'£,c t.
,� i?�..r L fi
i F g 1 �}., ➢
U• �F ' 1
'g is ,
XII. POPULATION AND HOUSING --
Would the project:
a) Induce substantial population growth in an
area, either directly (for example, by
proposing new homes and businesses) or ❑ ❑ ❑ Q
indirectly (for example, through extension of
roads or other infrastructure)?
b) Displace substantial numbers of existing
housing, necessitating the construction of ❑ ❑ ❑ Q
replacement housing elsewhere?
c) Displace substantial numbers of people,
necessitating the construction of replacement ❑ ❑ ❑ Q
housing elsewhere?
DISCUSSION:
The proposed project will not have a significant impact on population or housing.
MITIGATION:
None
Sources:
3,5
Town of Los Altos Hills
Initial Study Barron Creek Annual Maintenance
June 16, 2011
Page 21 of 29
t'�
❑
❑
Q
❑
�'' 1 z � '. �, �i't _ > � �.'�e � „s. � l
�i'f�.s✓ ".i s �. �v"'4
x 's k ��'a�
�' +'e��v"s,
� -- i � #".
_ tk Fn �z. � s'C. :: -^<e� y
� 4-� �.=��y�
�
� .
❑
Q
❑
❑
❑
Q
,_ a , . YSignrficant.,--..
0.S4gntfcant�wi -
44
S�gntficant
No impact}
uVI�hgatron4�;
P b a
Impact
t
2'C.,-."
#Fc
� a .. w�'�'Sa'�-.�rz{ . � �?£ � � h fk�� v ,:yaTk��a..z� ,�.,e�:y
4y",-r� ��,���,-'�.. �,") ��t ,S'.ti,?'S s
SY,�,+'`;Y����.e< $� �'£•.���s�
.� ;M'.2` £�an3�.3
r���z�-���n..'�r.'��s�'�"'� ...:n.;
XIII. PUBLIC SERVICES-- Would the project:
a) Would the project result in substantial
adverse physical impacts associated with the
provision of new or physically altered
governmental facilities, need for new or
physically altered governmental facilities, the
construction of which could cause significant
environmental impacts, in order to maintain
acceptable service ratios, response times or
other performance objectives for any of the
public services:
Fire protection?
Police protection?
Schools?
Parks?
Other public facilities?
❑ ❑ ❑ Q
❑
❑
❑
Q
❑
❑
❑
Q
❑
❑
❑
Q
❑
❑
❑
Q
❑
❑
❑
Q
DISCUSSION:
The proposed project will not have a foreseeableimpact on any public service or facility.
MITIGATION:
None
Sources:
3
Town of Los Altos Hills
Initial Study Barron Creek Annual Maintenance
June 16, 2011
Page 22 of 29
n__ ..h�'"ti F 'i " F k" S N�§'•`k4k'3 k"Y11
.ri
f{x,Yk .�
`5:t,.y_�f t
•t" -i 3.s€q�$ •gG F�i'"N.x k41,.,:`"f'�r�ig
} 3,,��ii q?'W_ i+h21.,.
E
k34. �•3, §&'°5.:�>4..,f.",x
5" `rt;Y _.. 40'x+ t«#:4".'
a �i ^moi_ �,.,?
f
,{A(: h i.:l i.✓ �juu�".."i',.
ri £ v F.,Ln--
�T �,s`zt i
iF:.
>'`"i)
,L d4`'i`�
c i
Pott nuall
_l�� Y ,� ,��
'Sa ndicantty► h� a
,ess Than
�,�:�
a
A tet�li t L
5�gn�fcant y
I7n act...
S�gnicant
Im acts a
cNoImpact__
5rh
p
XIV RECREATION ---Would the project:
a) Would the project increase the use of
existing neighborhood and regional parks or
other recreational facilities such that ❑ ❑ ❑ Q
substantial physical deterioration of the
facility would occur or be accelerated?
b) Does the project include recreational.
facilities or require the construction or
expansion of recreational facilities which ❑ ❑ ❑ Q
might have an adverse physical effect on the
environment?
DISCUSSION:
The proposed project will not have a foreseeable impact on recreation facilities.
MITIGATION:
None
Sources:
5,6
Town of Los Altos Hills
Initial Study Barron Creek Annual Maintenance
June 16, 2011
Page 23 of 29
elf- "J.3F Cry` -§} '�` r g +���� a
T+'
i
F '
3�C
�. dx a 5 2 3 z
t x y
sh�'i'a. W s; * ^" s
w '§d 1'" - z§
p °%
wi �y�i' i�.f'F. 4
': iyzt :} (* F.
fj {.%'�i� 1^ f" ?'3" tj'°5`%a W`;� ,�
+t i "iaY '+° b '.. �"
L 2.�
y f
'Potential)
Less Than
Less Than
Q
t ,jy
1
�
�Significant with .
MR
Pk"i
r
s rig � � � � �,
S► nifcant ,
g
�� �
Significant'
� g p s
Tm act
"i�..r.�i�r�i,
j,
..Y�,i} �xf �'s,�x: �' �r rf ,'s. � s a ms's. .-��'',.� �°�„b. 9�w p5`,i,'n
�� � ..r€M
"�a�.`h,i iSY✓, .�.:E�i, �P, ��},..Y���c.k
x, �Nl. �r� ,�F
s,�,iC'a,#'§, �.,wxtC'�}��. ,��. _.�'r'.c'
XV. TRANSPORTATION/TRAFFIC —
Would the project:
a) Cause an increase in traffic which is
substantial in relation to the existing traffic
load and capacity of the street system (i.e.,
result in a substantial increase in either the
number of vehicle trips, the volume to
capacity ratio on roads, or congestion at
intersections)?
b) Exceed, either individually or cumulatively,
a level of service standard established by the
county congestion management agency for
designated roads or highways?
c) Result in a change in air traffic patterns,
including either an increase in traffic levels or
a change in location that results in substantial
safety risks?
d) Substantially increase hazards due to a
design feature (e.g., sharp curves or dangerous
intersections) or incompatible uses (e.g., farm
equipment)?
e) Result in inadequate emergency access?
f) Result in inadequate parking capacity?
g) Conflict with adopted policies, plans, or
programs supporting alternative transportation
(e.g., bus turnouts, bicycle racks)?
DISCUSSION:
The project has no traffic impacts.
MITIGATION:
None
Sources:
1,3,5
❑ ❑ ❑ Q
❑ ❑ ❑ Q
❑
❑
❑
Q
❑
❑
❑
Q
❑
❑
❑
Q
❑
❑
❑
Q
Town of Los Altos Hills
Initial Study Barron Creek Annual Maintenance
June 16, 2011
Page 24 of 29
XVI. UTILITIES AND SERVICE SYSTEMS—
Would the project:
a) Exceed wastewater treatment requirements
of the applicable Regional Water Quality
❑
Control Board?
❑
b) Require or result in the construction of new
Q
water or wastewater treatment facilities or
expansion of existing facilities, the
❑
construction of which could cause significant
environmental effects?
c) Require or result in the construction of new
t
Fotent►ally , '
❑
LessEThan
could cause significant environmental effects?
$►gn►ficaut w►ti► x
serve the project from existing entitlements
rY
S►gnicant "�
�
S► n►facant
g
No Impact
-� _ k
iVl►t►gat►on r
�, 4
,, ; r
❑
Impact
Incorporation
Impact
'4'`
3�
r
z
f) Be served by a landfill with sufficient
�
3
❑
project's solid waste disposal needs?
EpN
❑
statutes and regulations related to solid waste?
DISCUSSION:
ii
k �
XVI. UTILITIES AND SERVICE SYSTEMS—
Would the project:
a) Exceed wastewater treatment requirements
of the applicable Regional Water Quality
❑
Control Board?
❑
b) Require or result in the construction of new
Q
water or wastewater treatment facilities or
expansion of existing facilities, the
❑
construction of which could cause significant
environmental effects?
c) Require or result in the construction of new
storm water drainage facilities or expansion of
❑
existing facilities, the construction of which
could cause significant environmental effects?
d) Have sufficient water supplies available to
serve the project from existing entitlements
❑
and resources, or are new or expanded
entitlements needed?
e) Result in a determination by the wastewater
treatment provider which serves or may serve
the project that it has adequate capacity to
❑
serve the project's projected demand in
addition to the provider's existing
commitments?
f) Be served by a landfill with sufficient
permitted capacity to accommodate the
❑
project's solid waste disposal needs?
g) Comply with federal, state, and local
❑
statutes and regulations related to solid waste?
DISCUSSION:
The proposed project will not have an impact on utility
and service systems.
MITIGATION:
None
Sources:
1,3,15
❑ ❑ Q
❑ ❑ Q
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Town of Los Altos Hills
Initial Study Barron Creek Annual Maintenance
June 16, 2011
Page 25 of 29
XVII. MANDATORY FINDINGS OF
SIGNIFICANCE -- Would the project:
a) Does the project have the potential to
degrade the quality of the environment,
substantially reduce the habitat of a fish or
wildlife species, cause a fish or wildlife
population to drop below self-sustaining El Ll L3
levels, threaten to eliminate a plant or animal
community, reduce the number or restrict the
range of a rare or endangered plant or animal
or eliminate important examples of the major
periods of California history or prehistory?
b) Does the project have impacts that are
individually limited, but cumulatively
considerable? ("Cumulatively considerable"
means that the incremental effects of a project ❑ ❑ ❑ Q
are considerable when viewed in connection
with the effects of past projects, the effects of
other current projects, and the effects of
probable future projects)?
c) Does the project have environmental effects
which will cause substantial adverse effects on ❑ ❑ ❑ Q
human beings, either directly or indirectly?
DISCUSSION:
The proposed project, as mitigated, will not result in a negative impact to the environment, wildlife, plant or historical
resource. The project does not have any foreseeable cumulative or unmitigated impacts as defined in this Initial Study.
MITIGATION:
None
Sources:
1-21
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XVII. MANDATORY FINDINGS OF
SIGNIFICANCE -- Would the project:
a) Does the project have the potential to
degrade the quality of the environment,
substantially reduce the habitat of a fish or
wildlife species, cause a fish or wildlife
population to drop below self-sustaining El Ll L3
levels, threaten to eliminate a plant or animal
community, reduce the number or restrict the
range of a rare or endangered plant or animal
or eliminate important examples of the major
periods of California history or prehistory?
b) Does the project have impacts that are
individually limited, but cumulatively
considerable? ("Cumulatively considerable"
means that the incremental effects of a project ❑ ❑ ❑ Q
are considerable when viewed in connection
with the effects of past projects, the effects of
other current projects, and the effects of
probable future projects)?
c) Does the project have environmental effects
which will cause substantial adverse effects on ❑ ❑ ❑ Q
human beings, either directly or indirectly?
DISCUSSION:
The proposed project, as mitigated, will not result in a negative impact to the environment, wildlife, plant or historical
resource. The project does not have any foreseeable cumulative or unmitigated impacts as defined in this Initial Study.
MITIGATION:
None
Sources:
1-21
Town of Los Altos Hills
Initial Study Barron Creek Annual Maintenance
June 16, 2011
Page 26 of 29
MITIGATION MEASURES INCLUDED IN THE PROJECT TO AVOID
POTENTIALLY SIGNIFICANT EFFECTS:
Aesthetic Measure 1: A revegetation plan will be prepared and implemented to compensate for the loss of
the nineteen willow trees. A minimum 1:1 replacement -to -removal ratio along the upper banks of the same
reach of the creek where the willows are being removed is required. . .Willow pole cuttings will be
installed along the channel banks to mitigate for the removal of the willows. This measure will reduce
impacts to a less -than -significant level.
Biologic Measure 1: Trees planned for removal should be removed during the non -breeding season
(September 1 through January 31). If it is not possible to avoid tree removal during the breeding season
(February 1 through August 31), a qualified biologist should conduct a pre -disturbance survey for tree -
nesting raptors and migratory birds in all trees planned for removal and immediately adjacent to the
disturbance zone no more than 30 days from the onset of the removal activities, if such disturbance will
occur during the breeding season. If nesting raptors and migratory birds are detected on the site during the
survey, a suitable activity -free buffer should be established around all active nests. The precise dimension
of the buffer (up to 250 feet) would be determined at that time and may vary depending on location and
species. Buffers should remain in place for the duration of the breeding season or until it has been
confirmed by a qualified biologist that all chicks have fledged and are independent of their parents. Pre -
disturbance surveys during the non -breeding season are not necessary for tree -nesting raptors and migratory
birds, as they are expected to abandon their roosts during disturbance activities. Implementation of the
above measures would mitigate impacts to tree -nesting raptors and migratory birds to a less -than -
significant level.
Biologic Measure 2: A revegetation plan wilt be prepared to compensate for the loss_ of the nineteen
willow trees. A minimum 1:1 replacement -to -removal ratio along the upper banks of the same reach of the
creek where the willows are being removed is required. The portion of the channel around the willows will
be temporarily dewatered via a cofferdam to allow for their removal. Willow pole cuttings will be installed
along the channel banks to mitigate for the removal of the willows. 'This measure will reduce impacts to a
less -than -significant level.
Cultural Measure 1: Upon discovering or unearthing any possible burial site as evidenced by human
skeletal remains or artifacts, the person making such discovery shall immediately notify the County of
Santa Clara Coroner and no further disturbance of the site may be made except as authorized by the County
Coordinator of Indian Affairs.
Noise Measure 1: Noise generating construction activities shall be limited to Monday through Saturday
between the hours of 8:00 am and 5:30 pm. No heavy noise generating equipment is allowed to be used on
Saturdays and no construction is allowed on Sundays or holidays as noted per Chapter 7, Sec.5-7-01 of the
Los Altos Hills Municipal Code.
Town of Los Altos Hills
Initial Study Barron Creek Annual Maintenance
June 16, 2011
Page 27 of 29
Source List:
1. Field Inspection
2. Project Plans
3. Planner's Knowledge of the Area
4. Los Altos Hills Land Use and Zoning Map
5. Los Altos Hills General Plan
6. Los Altos Hills Municipal Code
7. Assessor's Maps, Office of County Assessor, Santa Clara County, 2009-2010
8. State Department of Conservation, Farmland Mapping and Monitoring Program
9. 'BAAQMD CEQA Guidelines: Assessing the Air Quality Impacts of Projects and Plans, December
1999
10. State Department Fish and Game CNDDB Map
11. Santa Clara Valley Water District Map.
12. Geotechnical and Seismic Hazard Zones Map of Los Altos Hills, Cotton Shires and Associates,
December 2005
13. DTSC Hazardous Waste and Substance Sites List, California Environmental Protection Agency
14. Federal Emergency.Management Agency, Flood Insurance Rate Map, Los Altos Hills, May 18,
2009
15. Sanitary Sewer Map, Town of Los Altos Hills Engineering Department
16. Santa Clara County Municipal Code Chapter II Indian Burial Grounds (Title B Division B-6)
17. Biological Evaluation prepared by Live Oak Associates, dated April 13, 2011.
18. Investigation of Potential Waters of the United States Barron Creek prepared by Live Oak
Associates, dated December 6, 2010
19. Department of the Army letter date stamped March 29, 2011
20. CEQA Guidelines, 2010
21. Google Earth
Exhibit List:
1. Tree removal Figure 2, prepared by Live Oak Associates
Town of Los Altos Hills
Initial Study Barron Creek Annual Maintenance
June 16, 2011
Page 28 of 29
Mitigation Monitoring Program
Barron Creek Annual Maintenance
File # 83-11 Misc.
Mitigation Measure
Responsible
Department
Must Be
Completed B
Done
1
Aesthetic Measure 1: A
Public Works
After tree
revegetation plan will be
Department
removal.
prepared and implemented to
compensate for the loss of the
nineteen willow trees. A
minimum 1:1 replacement -to -
removal ratio along the upper
banks of the same reach of the
creek where the willows are
being removed is required.
Willow pole cuttings will be
installed along the channel
banks to mitigate for the
removal of the willows.
2
Biologic Measure 1: Trees
Public Works
Prior to the start
planned for removal should be
Department
of tree removal.
removed during the non -
breeding season (September 1
through January 31). If it is
not possible to avoid tree
removal during the breeding
season (February 1 through
August 31), a qualified
biologist should conduct a pre -
disturbance survey for tree -
nesting raptors and migratory
birds in all trees planned for
removal and immediately
adjacent to the disturbance
zone no more than 30 days
from the onset of the removal
activities, if such disturbance
will occur during the breeding
season. If nesting raptors and
migratory birds are detected
on the site during the survey, a
suitable activity -free buffer
should be established around
all active nests. The precise
dimension of the buffer (up to
250 feet) would be determined
at that time and may vary
depending on location and
species. Buffers should
remain in place for the
duration of the breeding
Town of Los Altos Hills
Initial Study Barron Creek Annual Maintenance
June 16, 2011
Page 2 of 29
season or until it has been
confirmed. by a qualified
biologist that all chicks have
fledged and are independent of
their parents. Pre -disturbance
surveys during the non -
breeding season are not
necessary for tree -nesting
raptors and migratory birds, as
they are expected to abandon
their roosts during disturbance
activities.
3
Biologic Measure 2: A
Public Works
Prior to the start
revegetation plan will be
Department
of tree removal.
prepared to compensate for the
loss of the nineteen willow
trees. A minimum 1:1
replacement -to -removal ratio
along the upper banks of the
same reach of the creek where
the willows are being removed
is required. The portion of the
channel around the willows
will be temporarily dewatered
via a cofferdam to allow for
their removal. Willow pole
cuttings will be installed along
the channel banks to mitigate
for the removal of the willows.
4
Cultural Measure 1: Upon
Public Works
During
discovering or unearthing any
Department
maintenance
possible burial site as
and tree
evidenced by human skeletal
remains or artifacts, the person
removal.
making such discovery shall
immediately notify the County
of Santa Clara Coroner and no
further disturbance of the site
may be made except as
authorized by the County
Coordinator of Indian Affairs.
4
Noise Measure 1: Noise
Public Works
During Grading
generating construction
Department
Operations and
activities shall be limited to
Tree removal
Monday through Saturday
between the hours of 8:00 am
and 5:30 pm. No heavy noise
generating equipment is
allowed to be used on
Saturdays and no construction
is allowed on Sundays or
holidays as noted per Chapter
7, Sec.5-7-01 of the Los Altos
Hills Municipal Code.
Attachment 2
TOWN OF LOS ALTOS HILLS
NEGATIVE DECLARATION
PROJECT TITLE: Barron Creek Annual Maintenance
PREPARED BY: Cynthia Richardson, Consulting Planner
NAME AND ADDRESS OF PROJECT SPONSOR:
Town of Los Altos Hills
26379 Fremont Road
Los Altos Hills, CA 94022
LOCATION OF PROJECT: 26170 West Fremont Road, Los Altos Hills, CA 94022
APN #175-35-036
PROJECT DESCRIPTION: The proposed project is for annual maintenance of the aforementioned
reach of Barron Creek. This reach of the. creek is currently overgrown with non-native, invasive
vegetation in its downstream half, and, debris has accumulated at the base of several willows located
within the channel bed at the upstream end, obstructing the flow of water through the channel. To keep
the channel clear of debris and maintain an unobstructed flow of water, the Town is proposing to clear
out weeds growing within the channel on an annual basis and remove up to nineteen willows located
within the channel bed at the upstream end of the site. The portion o f the channel around the willows
will be temporarily dewatered via a cofferdam to allow for their removal. Willow pole cuttings will be
installed along the channel banks to mitigate for the removal of the willows trees.
FINDING: The Town of Los Altos Hills has completed a review of the proposed project, and on the
basis of the attached Initial Study, has determined that the project, as mitigated, will reduce impacts to a
less than significant level.
MITIGATION MEASURES INCLUDED IN THE PROJECT TO AVOID POTENTIALLY
SIGNICIANT EFFECTS:
Aesthetic Measure 1: A revegetation plan will be prepared and implemented to compensate f6r the loss
of the nineteen willow trees. A minimum 1:1 replacement -to -removal ratio along the upper banks of the
same reach of the creek where the willows are being removed is required. . Willow pole cuttings will
be installed along the channel banks to mitigate for the removal of the willows. This measure will
reduce impacts to a less -than -significant level.
Biologic Measure 1: Trees planned for removal should be removed during the non -breeding season
(September 1 through January 31). If it is not possible to avoid tree removal during the breeding season
(February 1 through August 31), a qualified biologist should conduct a pre -disturbance survey for tree -
nesting raptors and migratory birds in all trees planned for removal and immediately adjacent to the
Mitigation Measures
Barron Creek Annual Maintenance
June 16, 2011
Page 2
disturbance zone no more than 30 days from the onset of the removal activities, if such disturbance will
occur during the breeding season. If -nesting raptors and migratory birds are detected on the site during
the survey, a suitable activity -free buffer should be established around all active nests. The precise
dimension of the buffer (up to 250 feet) would be determined at that time and may vary depending on
location and species. Buffers should remain in place for the duration of the breeding season or until it
has been conf rmed by a qualified biologist that all chicks have fledged and are independent of their
parents. Pre -disturbance surveys during the non -breeding season are not necessary for tree -nesting
raptors and migratory birds, as they are expected to abandon their roosts during disturbance activities.
Implementation of the above measures would mitigate impacts to tree -nesting raptors and migratory
birds to a less -than -significant level.
Biologic Measure 2: A revegetation plan will be prepared to compensate for the loss of the nineteen
willow trees. A minimum 1:1 replacement -to -removal ratio along the upper banks of the same reach of
the creek where the willows are being removed is required. The portion of the channel around the
willows will be temporarily dewatered via a cofferdam to allow for their removal. Willow pole cuttings
will be installed along the channel banks to mitigate for the removal of the willows. This measure will
reduce impacts to a less -than -significant level.
Cultural Measure 1: Upon discovering or unearthing any possible burial site as evidenced by human
skeletal remains or artifacts, the person making such discovery shall immediately notify the County of
Santa Clara Coroner and no further disturbance of the site may be made except as authorized by the
County Coordinator of Indian Affairs.
Noise Measure 1: Noise generating construction activities shall be limited to Monday through
Saturday between the hours of 8:00 am and 5:30 pm. No heavy noise generating equipment is
allowed to be used on Saturdays and no construction is allowed on Sundays or holidays as noted per
Chapter 7, Sec.5-7-01 of the Los Altos Hills Municipal Code.
Debbie Pedro, AICP, Planning Director
TOWN OF LOS ALTOS HILLS
Circulated on:
Adopted on:
Date
LIVE OAK ASSOCIATES, INC.
an Ecological Consulting Firm
BARRON CREEK
BIOLOGICAL EVALUATION
TOWN OF LOS ALTOS HILLS, CALIFORNIA
Prepared by
LIVE OAK ASSOCIATES, INC.
. Rick Hopkins, Ph.D., Principal and Senior Wildlife Ecologist
Davinna Ohlson, M.S., Senior Project Manager and Plant/Wildlife Ecologist
Neal Kramer, M.S., Botanist and Certified Arborist
Prepared for
Town of Los Altos Hills
Public Works Department
Attn: John Chau
26379 Fremont Road
Los Altos Hills, CA 94022
April 13, 2011
Attachment 3
PN 1435-01
San Jose: 6840 Via del Oro, Suite 220 *San Jose, CA 95119. Phone: (408) 224-8300. Fax: (408) 2241411
Oakhurst P.O. Box 2697 49430' Road: 426; Suite C r Oakhurst; CA 93644. Phone: (559) 642-4880 . Fax: (559) 642=4883
Bakersfield: 8200 Stockdale Highway, M10-293 . Bakersfield, CA 93311
TABLE OF CONTENTS
1.0 INTRODUCTION.............................................................................................................. 1
1.1 PROJECT DESCRIPTION.............................................................................................
3
2.0 EXISTING CONDITIONS.................................................................................................
4
2.1 BIOTIC HABITATS......................................................................................................
4
2.2 MOVEMENT CORRIDORS..........................................................................................
7
2.3 SPECIAL STATUS PLANTS AND ANIMALS...........................................................
8
2.4 JURISDICTIONAL WATERS.....................................................................................
17
3.0 IMPACTS AND MITIGATIONS....................................................................................
18
3.1 SIGNIFICANCE CRITERIA.......................................................................................
18
3.2 RELEVANT GOALS, POLICIES, AND LAWS .........................................................
19
3.2.1 Threatened and Endangered Species........................................................................
19
3.2.2 Migratory Birds.........................................................................................................
20
3.2.3 Birds of Prey.............................................................................................................
20
3.2.4 Wetlands and Other Jurisdictional Waters................................................................
20
3.2.5 Local Ordinances, Policies, and Habitat Conservation Plans ...................................
22
3.3 IMPACTS AND MITIGATIONS SPECIFIC TO THE PROJECT SITE ....................
22
3.3.1 Loss of Habitat for Special Status Plants..................................................................
22
3.3.2 Loss of Habitat for Special Status Animals..............................................................
23
3.3.3 Disturbance to Active Raptor and Migratory Bird Nests ..........................................
23
3.3.4 Disturbance to Waters of the United States or Riparian Habitats .............................
24
3.3.5 Loss of Habitat for Native Wildlife..........................................................................
25
3.3.6 Interference with the Movement of Native Wildlife .................................................
26
3.3.7 Degradation of Water Quality in Seasonal Drainages, Stock Ponds, and Downstream
Waters...................................................................................................................................
26
3.3.8 Local Ordinances or Habitat Conservation Plans .....................................................
27
REFERENCES.............................................................................................................................
28
APPENDIX A: VASCULAR PLANTS OF THE STUDY AREA ..............................................
30
Live Oak Associates, Inc. Barron Creek Biological Evaluation
PN 1435-61
1.0 INTRODUCTION
Live Oak Associates, Inc. (LOA), has prepared the following report, which describes the biotic
resources of approximately 624 linear feet of Barron Creek located off -of West Fremont Road in
the Town of Los Altos Hills, Santa Clara County, California, and evaluates likely impacts to
these resources resulting from channel maintenance activities. The project site is located in the
Palo Alto 7.5" U.S. Geological Survey (USGS) quadrangle in section 25 of township 6 south,
range 3 west,
Maintenance activities can damage or modify biotic habitats used by- sensitive plant and wildlife
species. In such cases, these activities may be regulated by state or federal agencies, subject to
provisions of the California Environmental Quality Act (CEQA), and/or covered by policies and
ordinances of the Town of Los Altos Hills. This report addresses issues related to: 1) sensitive
biotic resources occurring on the site; 2) the federal, state, and local laws regulating such
resources, and 3) mitigation measures which may be required to reduce the magnitude of
anticipated impacts. As such, the objectives of this report are to:
• Summarize all site-specific information related to existing biological resources;
• Make reasonable inferences about the biological resources that could occur onsite based
on. habitat suitability and the proximity of the site to a species' known range;
• Summarize all state and federal natural resource protection laws that may be relevant to
possible future site development;
• Identify and discuss project impacts to biological resources likely to occur on the site
within the context of CEQA or any state or federal laws; and
• Identify avoidance and mitigation measures that would reduce impacts to a less -than -
significant level as -identified by CEQA and that are generally consistent with
recommendations of the resource agencies for affected biological resources.
1
Live Oak Associates, Inc. Barron Creek Biological Evaluation
IDE
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Live Oak Associates, Inc.
Barron Creek B.E.
Site / Vicinity Map
ate Project # Figure #
3/2512011 1435-01 1
1 ._ J
PN 1435-01
The analysis of impacts, as discussed in Section 3.0 of this report, is -based on the known and
potential biotic resources of the site, discussed in Section 2.0. Sources of information used in the
preparation of this analysis included: 1) the California Natural Diversity Data Base (CDFG
2011), 2) the Inventory of Rare and Endangered Vascular Plants of California (CNPS 2011),
and 3) manuals and references .related to plants and animals of Santa Clara County. A
reconnaissance -level field survey of the study area was conducted on August 4, 2010, by LOA
ecologist Davinna Ohlson and LOA botanist Neal Kramer, at which time the principal biotic
habitats of the site were identified, and the constituent plants and animals of each were noted.
1.1 PROJECT DESCRIPTION
The proposed project is for annual maintenance of the aforementioned reach of Barron Creek.
This reach of the creek is currently overgrown with non-native, invasive vegetation in its
downstream half, and debris has accumulated at the base of several willows located within the
channel bed at the upstream end', obstructing the flow of water through the channel. To keep the
channel clear of debris and maintain an unobstructed flow of water, the Town is proposing to
clear out weeds growing within the channel on an annual basis and remove up to nineteen
willows located within the channel bed at the upstream end of the site. The portion of the
channel around the willows will be- temporarily dewatered via a cofferdam to allow for their
removal. Willow pole cuttings will be installed along the channel banks- to mitigate for the
removal of the willows.
3
Live Oak Associates, Inc. Barron Creek Biological Evaluation
PN 1435-01
2.0 EXISTING CONDITIONS
The project site is located off of West Fremont Road, across from Donelson Place, in the Town
of Los Altos Hills, Santa Clara County, California. The site is bounded by West Fremont Road
to the north, a residential estate to the east, a single-family residence to the south, and a field and
single-family residences to the west. Topographically, the site is relatively level at
approximately 215 ft. (66 m) National Geodetic Vertical Datum. The surrounding land use is
primarily residential.
Three soil types from two soil complexes, Urbanland-Cropley and Literr-Urbanland-Merbeth,
were identified on the project site (Figure 2; NRCS 2010). Urban land soils are derived from
disturbed and human -transported material. Cropley soils consist of alluvium derived from
calcareous shale. Literr-and Merbeth soils consist of old, eroded alluvium. None of these soils
are considered hydric, although hydric inclusions may occur.
Santa Clara County experiences a Mediterranean climate with warm, dry summers and cool, wet
winters. The average annual daytime temperature in the general vicinity of the site is 69° F.
Average annual precipitation in the general vicinity of the site is 15 inches, nearly all of which
falls between November and April. Stormwater runoff infiltrates the soils of upland areas
immediately adjacent to Barron creek, but when field capacity has been reached, gravitational
water drains into the creek.
2.1 BIOTIC HABITATS
The project site includes a reach of Barron Creek and the immediately adjacent upland habitat
along the channel banks. The creek has been channelized and straightened from its original
alignment, and it enters and exits the site via culverts. The immediately upstream and
downstream reaches of the creek are sited underground. This reach of Barron Creek appears to
convey water perennially. Surrounding lands consist of ruderal fields and private residences. A
list of the vascular plant species observed on the project site is provided in Appendix A.
4 "
Live Oak Associates, Inc. Barron Creek Biological Evaluation
PN 1435-01
The bed and banks of the downstream two-thirds of the channel are lined with riprap. The
downstream third of the channel is largely devoid of vegetation within the channel itself and is
lined with arroyo willows (Salix lasiolepis) along its upper banks.
The middle third of the channel supports a moderately dense mixture of native and non-native
herbaceous vegetation. Native plants supported along this reach of the site include .California
willowherb (Epilobium ciliatum ssp. ciliatum) tall flatsedge (Cyperus eragrostis), and broadleaf
cattail (Typha latifolia); non-native vegetation includes Italian thistle (Carduus pycnocephalus),
bristly ox -tongue (Helminthotheca echioides), prickly lettuce (Lactuca serriola), and curly dock
(Rumex crispus). Trees were absent from this portion of the channel. Upland areas along this
reach of the channel immediately beyond the banks consist of ruderal, non-native vegetation
such as Italian thistle, bristly ox -tongue, and ripgut brome (Bromus diandrus).
The upper third of the channel has a natural bottom and banks and is shaded by arroyo willows,
Pacific willows (Salix lasiandra ssp. lasiandra), and red willows (Salix laevigata) occurring in
the channel bed and along the lower banks. Herbaceous vegetation occurring in the channel bed
is relatively sparse and includes California willowherb, water bentgrass (Agrostis viridis), and
rabbitsfoot grass (Polypogon monspeliensis). Upland areas immediately adjacent to this portion
of the channel consist of landscape trees such as coast redwood (Sequoia sempervirens), Italian
cypress (Cupressus sempervirens), liquidambar (Liquidambar styraciflua), and African sumac
(Rhus lancea).
Because it has been manipulated, is isolated from other riparian habitat due to the up- and
downstream reaches of the creek being underground, and lacks structural and floral diversity, the
site does not provide as high a habitat value as other, more natural riparian habitats. The site
provides a source of drinking water for species occurring in the surrounding habitats and may
also provide breeding habitat for amphibians and reptiles such as pacific treefrogs (Hyla regilla)
and western fence lizards (Sceloporus occidentalis). While no stick nests were observed in any
of the trees on the site, birds that could occur on the site include the western scrub jay
(Aphelocoma californica) and northern mockingbird (Mimus polyglottos). Raptors that could
forage over the site include the turkey vulture (Cathartes aura) and red-tailed hawk (Buteo
Live Oak Associates, Inc. Barron Creek Biological Evaluation
PN 1435-01
jamaicensis). Domestic dogs (Canis familiaris) and feral house cats (Fells catus) are likely to
occur on the site. Raccoons (Procyon lotor) may also forage along the creek.
2.2 MOVEMENT CORRIDORS
Many terrestrial animals need more than one biotic habitat in order to perform all of their
biological activities. With increasing encroachment of humans on wildlife habitats, it has
become -important to establish and maintain linkages, or movement corridors, for animals to be
able to access locations containing different biotic resources that are essential to maintaining
their life cycles. Terrestrial animals use ridges, canyons, riparian areas, and open spaces'to travel
between their required habitats.
The importance of an area as a movement corridor depends on the species in question and its
consistent use patterns. Animal movements generally can be divided into three major behavioral
categories:
• Movements within a home range or territory;
• Movements. during migration; and
• Movements during dispersal.
While no detailed study of animal movements has been conducted for the study area, knowledge
of the site, its habitats, and the ecology of the species potentially occurring onsite permits
sufficient predictions about the types of movements occurring .in the region and whether or not
proposed development would constitute a significant impact to animal movements.
As noted in Section 2.1, wildlife species may use the site as part of their home range and
dispersal movements. This reach of Barron Creek may facilitate .their movements within and
through the site. However, the surrounding development serves as a barrier to regional wildlife
movements. Because it originates and terminates on the site, this reach of the creek does not
serve as a wildlife movement corridor or contribute to or link pathways occurring at the regional
level.
7
Live Oak Associates, Inc. Barron Creek Biological Evaluation
PN 1435-01
2.3 SPECIAL STATUS PLANTS AND ANIMALS
Several species of plants and animals within the state of California have low populations and/or
limited distributions. Such species may be considered "rare" and are vulnerable to extirpation as
the state's human population grows and the habitats these species occupy are converted to
agricultural, urban, and other uses. As described more fully in Section 3.2, state and federal laws
have provided the California Department of Fish and Game (CDFG) and the U.S. Fish and
Wildlife Service (USFWS) with a mechanism for conserving and protecting the diversity of plant
and animal species native to the state. A sizable number of native plants and animals have been
formally designated as "threatened" or "endangered" under state and federal endangered species
legislation. Others have been designated as candidates for such listing. Still others have been
designated as "species of special concern" by the CDFG. The CDFG and California Native Plant
Society (CNPS) have developed their own set of lists of native plants considered rare, threatened,
or endangered. Collectively, these plants and animals are referred to as "special status species."
A number of special status plants and animals occur in the site's vicinity (Fig. 3). These species
and their potential to occur in the study area are listed in Table 1 on the following pages.
Sources of information for this table included California's Wildlife, Volumes I, Il, and III (Zeiner
et. al 1988), California Natural Diversity Data Base (CDFG 2011), Endangered and Threatened
Wildlife and Plants (USFWS 2011), State and Federally Listed Endangered and Threatened
Animals of California (CDFG 2011), and The California Native Plant Society's Inventory of
Rare and Endangered Vascular Plants of California (CNPS 2011). This information was used
to evaluate the potential for special status plant and animal species that occur on the site. Figure
3 depicts the location of special status species found by the California Natural Diversity Data
Base (CNDDB). It is important to note that the CNDDB is a volunteer database; therefore, it
may not contain all known or gray literature records:
A search of published accounts for all relevant special status plant and animal species was
conducted for the Palo Alto USGS 7.5" quadrangles in which the project site occurs and for the
eight surrounding quadrangles (Redwood Point, Newark, Mountain View, Cupertino, Mindego
Hill, La Honda, Woodside, and San Mateo) using the California Natural Diversity Data Base
Live Oak Associates, Inc. Barron Creek Biological Evaluation
PN 1435-01
Rarefind (CDFG 2011). All species listed as occurring in these quadrangles on CNPS Lists IA,
1B, 2, 3, or 4 were also reviewed.
Serpentine and alkaline soils are completely lacking from the site; as such, those species that are
uniquely adapted to vernal pools or to serpentine or alkaline conditions are considered absent
from the site. These species include the San Mateo thorn -mint (Acanthomintha duttonii), alkali
milk -vetch (Astragalus tener var. tener), San Joaquin spearscale (Atriplex joaquiniana
Congdong's tarplant (Centromadia parryi ssp. congdonii), fountain thistle (Cirsium fontinale
var. fontinale), San Mateo woolly sunflower (Eriophyllum latilobum), Hoover's button -celery
(Eryngium aristulatum var. hooveri), Hillsborough chocolate lily (Fritillaria biflora var. biflora),
Marin western flax (Hesperolinon congestum), legenere (Legenere limosa), serpentine
leptosiphon (Linanthus ambiguus); Crystal- Springs lessirigia (Lessingia arachnoidea); woolly-
headed lessingia (Lessingia hololeuca), woodland woollythreads (Monolopia gracilens),
pincushion navarretia (Navarretia myersii ssp. myersii), saline clover (Trifolium depauperatum
var. hydrophilum), and caper -fruited tropidocarpum (Tropidocarpum capparideum). Other plant
species occur in habitats not present in the study area (e.g., chaparral, coastal scrub, etc.) and,
therefore, are also considered absent from the site. These species include'Anderson's manzanita
(Arctostaphylos andersonii), Montara manzanita (Arctostaphylos montaraensis), Kings
Mountain manzanita (Arctostaphylos regismontana), coastal marsh milk -vetch (Astragalus
pycnostachyus var. pycnostachyus), Brewer's calandrinia (Calandrinia breweri), Oakland star -
tulip (Calochortus umbellatus), San Francisco Bay spineflower (Chorizanthe cuspidata var.
cuspidata), Santa Clara red ribbons (Clarkia concinna ssp. automixa), San Francisco collinsia
(Collinsia multicolor), Point Reyes bird's -beak (Cordylanthus maritimus ssp. palustris), Ben
Lomond buckwheat (Eriogonum nudum var. decurrens), San Francisco wallflower (Erysimum
franciscanum var. crassifolium), short -leaved evax (Hesperevax sparsiora var. brevifolia),
coast lily (Lilium maritimum), San Mateo tree lupine (Lupinus eximius), arcuate bush -mallow
(Malacothamnus arcuatus), Hall's bush -mallow (Malacothamnus hallii), white -flowered rein
orchid (Piperia candida), Choris' popcorn -flower (Plagiobothrys chorisianus var. chorisianus),
hairless popcorn -flower (Plagiobothrys glaber), Oregon polemonium (Polemonium carneum),
and slender -leaved pondweed (Potamogeton filiformis), and California seablite (Suaeda
californica).
Live Oak Associates, Inc. Barron Creek Biological Evaluation
PN 1435-01
Wildlife species that would not be expected to occur on the site because the habitats necessary to
support them are absent include the Bay checkerspot butterfly (Euphydryas editha bayensis),
Myrtle's silverspot (Speyeria zerene myrtleae), California black rail (Laterallus jamaicensis
coturniculus), California clapper rail (Rallus longirostris obsoletus), western snowy plover
(Charadrius alexandrinus nivosus), California least tern (Sternula antillarum browni), saltmarsh
common yellowthroat (Geothlypis trichas sinuosa), Alameda song sparrow (Melospiza melodia
pusillula), salt -marsh wandering shrew (Sorex vagrans halicoetes), and salt -marsh harvest mouse
(Reithrodontomys raviventris).
Table 1: Special status species that
d occur
in the project
Common and scientific names Status General habitat descnptlon Occurrence in the sturdy area
PLANTS(adapted from CDFG1
. CNPS
2011)
Habitat: Cismonatne
Speciesd as Threatened. ..ngered under the State andlor Federal
t Endangered .-
�
Common,and scientific names Status General habitat descr►ption *O ccurrence`m`thectudy area
Allium peninsulare var.
, ,
Contra Costa goldfields
FE, CRPR
Habitat: Alkaline soils in
Absent. Alkaline soils are absent from
Losthenia conjugens
1B
clay and volcanic soils and
mesic valley and foothill
the site.
often on serpentinite.
grasslands and vernal pools.
Elevation: 52-300 meters.
Elevation: 0-470 meters.
Blooms: May June.
Bent -flowered fiddleneck
CRPR 1B
Blooms: March June.
Absent. The site provides poor habitat
White -rayed pentachaeta
FE, CE,
cismontane woodland, and
Habitat: Cismontane
Absent. The site provides poor habitat
Pentachoeta bellidiflora
CRPR 1B
been observed within ten miles of the
woodland and valley and
for this species and does not support
grasslands.
site.
foothill grasslands, often on
serpentine soils. The nearest
serpentinite.
documented occurrence of this species
Elevation: 35-620 meters.
is more than ten miles from the site.
Blooms: March—May.
Table 1: Special status speciescould occur in the project . a
PLANTS (adapted from CDFG 2011 and CNPSz 2011)
Other special status plants',listed by CNPS
Common and scientific names Status General habitat descnptlon Occurrence in the sturdy area
Franciscan onion
CRPR 1B
Habitat: Cismonatne
Absent. Suitable habitat for this
Allium peninsulare var.
woodland and valley and
species is absent from the site.
franciscanum
foothill grassland. Occurs on
clay and volcanic soils and
often on serpentinite.
Elevation: 52-300 meters.
Blooms: May June.
Bent -flowered fiddleneck
CRPR 1B
Habitat: Coastal bluff scrub,
Absent. The site provides poor habitat
Amsinckia lunaris
cismontane woodland, and
for this species. This species has not
valley and foothill
been observed within ten miles of the
grasslands.
site.
Elevation: 3-500 meters.
Blooms: March—June.
11
Live Oak Associates, Inc. Barron Creek Biological Evaluation
PN 1435-01
(adaptedPLANTS
plantsOther special status by CNPS
y5.'�� k 4 � �J 1 ,�+`�*vE �- 4 5 P''18 {$� J i � �i9Y`✓9b:�*-•F" '3.'� �'.yil i Y3 l3?SS�'"'� �� i'R 3" § .?"� .Y�z-s.L1� 3� o. §`f„p 6 'a1.:. � # �d � . ��
Common and scientific names, Status! ' habitat Tescripti n= `*Occurrencenthe studyareag�' f
�GeneraT
Round -leaved filaree CRPR 1B
Habitat: Cismontane
Absent. Clay soils are absent from the
California macrophylla
woodlands and valley and
site. Upland areas of the site provide
- foothill -grasslands on -clay
very, poor habitat for this species. This
soils.
species has not been observed in the
Elevation: 15-1200 meters.
region since 1896.
Blooms: March -May.
Western leatherwood
CRPR 1B
Habitat: Broadleafed upland
Unlikely. The site provides poor
Dirca occidentalis
forest, closed -cone
habitat for this species. This species
coniferous forest, chaparral,
was observed in 2008 approximately
cismontane woodland,
2.5 miles southwest of the site.
North Coast coniferous
forest, riparian forest, and
.--mesic riparian -woodlands::
- - - — - - -
Elevation: 50-395 meters.
Blooms: January -March.
Fragrant fritillary
CRPR 1B- -
Habitat: Cismontane
Absent. Upland areas of the site
Fritillaria liliacea
woodland, coastal prairie,
provide very poor habitat for this
coastal scrub, and valley and
species. The site does not support
foothill grasslands. Often
serpentine soils.
occurs on serpentinite.
Elevation: 3-410 meters.
Blooms: February -April.
Loma Prieta hoita
CRPR 1B
Habitat: Chaparral,
Absent. The site provides poor habitat
Hoita strobilina
cismontane woodland, and
for this species and does not support
riparian woodland. Usually
serpentine soils. This species was not
occurs on serpentinitic or
observed on the site during the August
mesic soils.
2010 field survey. The only
Elevation: 30-860 meters.
documented occurrence in the region
Blooms: May -October,
is from 1913 more than ten miles from
the site.
Davidson's bush -mallow
CRPR 16
Habitat: Chaparral,
Absent. The site provides poor habitat
Malacothamnus davidsonii
cismontane woodland,
for this species. This species was not
coastal scrub, and riparian
observed on the site during the August
woodland.
2010 field survey. The most recent
Elevation: 185-855 meters.
documented occurrence of this species
Blooms: June -January.
in the region is from 1936.
Robust monardella
CRPR SB
Habitat: Broadleafed upland
Absent. Upland areas of the site
Monardella villoso ssp. globosa
forest openings, chaparral
provide poor habitat for this species.
openings, cismontane
The nearest documented occurrence of
woodland, coastal scrub,
this species is more than four miles
and valley and foothill
southeast of the site.
grasslands.
Elevation: 100-915 meters.
Blooms: June July.
12
Live Oak Associates, Inc. Barron Creek Biological Evaluation
PN 1435-01
Dudley's lousewort
CRPR 1B
Habitat: Maritime chaparral,
Absent. Upland areas of the site
Pedicularis dudleyi
FT, CT, CSC
cismontane woodland,
provide poor habitat for this species.
Ambystoma californiense
North Coast coniferous
This species has not been documented
forest, and valley and
within five miles of the site.
foothill grasslands.
Elevation: 60-900 meters.
California red -legged frog
FT, CSC
Blooms: April—June.
Absent. The reach of Barron Creek
San Francisco campion
CRPR 1B
Habitat: Coastal bluff scrub,
Absent. Upland areas of the site
Silene verecunda ssp. verecunda
chaparral, coastal prairie,
provide poor habitat for this species.
coastal scrub, and valley and
The nearest documented occurrence of
foothill grasslands. Occurs
this species is from 1983 approximately
on sandy soils.
ten miles from the site.
Elevation: 30-645 meters.
Blooms: March June.
San Francisco owl's -clover
CRPR 1B
Habitat: Coastal prairie,
Absent. The site provides poor habitat
Triphysaria floribunda
coastal scrub, and valley and
for this species and does not support
foothill grasslands. Usually
serpentine soils. The nearest
occurs on serpentinite.
documented occurrence of this species
Elevation: 10-160 meters.
is from 1932 more than ten miles from
Blooms: April—June.
the site.
Steel head—central California coast
DPS
Oncorhynchus mykiss irideus
FT
Migrate up fresh water
rivers or streams in the
spring and spend the
remainder of the time in the
ocean.
Absent. Steelhead have not been
documented in Barron Creek.
Substantial barriers exist between any
source population and this reach of
Barron Creek.
California tiger salamander
FT, CT, CSC
Breeds in vernal pools and
Absent. Breeding and aestivation
Ambystoma californiense
stock ponds of central
habitat is absent from the site.
California; adults aestivate in
grassland habitats adjacent
to the breeding sites.
California red -legged frog
FT, CSC
Rivers, creeks and stock
Absent. The reach of Barron Creek
Rana draytonii
ponds of the Sierra foothills
occurring onsite has a shallow water
and coast range, preferring
depth and lacks pooling areas
pools with overhanging
preferred by this species. CRLF have
vegetation.
not been documented along Barron
Creek.
Live Oak Associates, Inc. Barron Creek Biological Evaluation
PN 1435-01
Table 1: Special status species that occur in the project vicinity.
(adaptedANIMALS
Sliecies Listed as Threatened or Endangered under the State andlor Federal Endangered Species Acts
hkx � v � � i �T�b✓z ` t "3 t;'" l ; �, fi k r .fi d � �' r - �t t�' � � b # � ,k'".f
Common and scientific names Status General habitat description > *Occurrence m the studareaF
u_ _.:. � n ,..t
San Francisco garter snake
FE, CE
Freshwater marshes, ponds, Absent. The reach of Barron Creek
Thamnophis sirtalis tetrotaenia
;a
and slow-moving streams, occurring onsite has a shallow water
Foothill yellow -legged frog CSC
Partly shaded, shallow,
preferring dense cover and depth and lacks the dense cover
Rana boylii
swiftly -flowing streams and
water depths of at least one preferred by this species.
riffles with rocky substrate
foot.
Peregrine falcon
CE, CP
Individuals breed on cliffs in Unlikely. Suitable breeding habitat is
Falco peregrinus anatum
the Sierra or in coastal absent from the site. The site would
Western pond turtle
CSC
habitats; occurs in many not be considered suitable foraging
Absent. The reach of Barron Creek
Actinemys marmorata
habitats of the state during habitat for this species.
rivers and creeks of central
occurring onsite has a shallow water
migration and winter.
Bank swallow
Ci'
Nests in large colonies, Absent. Suitable habitat for this
Riparia riparia
excavating nest burrows in species is absent from the site.
This species has not been documented
steep riverbank cliffs, gravel
along Barron Creek or within three
pits, and highway cuts.
Table 1: Special status species that occur in the project vicinity.
(adaptedANIMALS
SpecialCalifornia Species of .-
Common'andscienbfic namesx Status General habitat description
*OccurHrence m the studyareai
;a
. +`
Foothill yellow -legged frog CSC
Partly shaded, shallow,
Absent. Onsite habitat for this species
Rana boylii
swiftly -flowing streams and
is poor. This species has not been
riffles with rocky substrate
documented along Barron Creek, and
in a variety of habitats.
the nearest documented occurrence is
more than ten miles from the site.
Western pond turtle
CSC
Open, slow-moving water of
Absent. The reach of Barron Creek
Actinemys marmorata
rivers and creeks of central
occurring onsite has a shallow water
California with rocks and
depth and lacks suitable basking areas.
logs for basking.
This species has not been documented
along Barron Creek or within three
miles of the site.
White-tailed kite
CP
Open grasslands and
Unlikely. Nesting habitat is marginal,
Elanus leucurus
agricultural areas
and foraging habitat is absent from the
throughout central
site.
California.
Northern harrier
CSC
Frequents meadows,
Absent. Suitable breeding and foraging
Circus cyaneus
grasslands, open rangelands,
habitat is absent from the site.
freshwater emergent
wetlands; uncommon in
wooded habitats.
14
Live Oak Associates, Inc. Barron Creek Biological Evaluation
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15
Live Oak Associates, Inc. Barron Creek Biological Evaluation
in the project
speciesTable 1: Special status d occur
(adaptedANIMALS
Species
California Species of Special Concern and Protected
=Commcnand°scienfic names_l5tatus
General #dab tat description*Occurrence ine studyarea
��
Burrowing owl
CSC
Open, dry grasslands, Absent. Suitable breeding and foraging
Athene cunicularia
deserts and ruderal areas. habitat is absent from the site.
Requires suitable burrows.
This species is often
associated with California
ground squirrels.
Long-eared owl
CSC
Frequents dense, riparian
Absent. Riparian habitat on the site is
Asio otus
and live oak thickets near
marginal and lacks the dense thickets
meadow edges and nearby
preferred by this species. The nearest
woodland and forest
documented occurrence of this species
habitats. Breed in valley
N from 1987 and approximately five
foothill hardwood up to
miles southwest of the site.
-- -------- -- - — ..-_..... _ ....__
--
—- ------
ponderosa pine habitats.
Short -eared owl
CSC
Frequents annual and
Absent. Suitable breeding and foraging
Asio flammeus
perennial grasslands,
habitat is absent from the site.
prairies, meadows, irrigated
land, and saline and fresh
emergent marshes with
elevated vegetated sites for
perches, roosting and
nesting.
Black swift
CSC
Migrants and transients
Unlikely. Suitable breeding and
Cypseloides niger
found throughout many
foraging habitats are absent from the
habitats of state. Breeds on
site. However, this species may
steep cliffs or ocean bluffs,
occasionally pass through the site.
or in cracks and crevasses of
inland deep canyons.
Vaux's swift
CSC
Migrants and transients
Unlikely. Suitable breeding and
Chaetura vauxi
move through the foothills
foraging habitats are absent from the
of the western Sierra in
site. However, this species may
spring and late summer.
occasionally pass through the site.
Breeds in coniferous forests.
Yellow warbler
CSC
Nests in riparian thickets,
Possible. Willows on the site provide
Dendroica petechia brewsteri
especially in willows. Also
potential, albeit limited, breeding
frequents shrubby areas and
habitat for this species.
old fields.
Tricolored blackbird
CSC
Breeds near fresh water,
Absent. Suitable breeding and foraging
Agelaius tricolor
primarily emergent
habitat is absent from the site. The
wetlands, with tall thickets.
nearest documented'occurrence of this
Forages in nearby grassland
species is from 1971 more than ten
and cropland habitats.
miles east of the site.
Pallid bat
CSC
Roosts in rocky outcrops,
Unlikely. Suitable roosting habitat is
Antrozous pallidus
cliffs, and crevices with
absent from the site itself. Foraging
access to open habitats for
habitat is marginal, at best.
foraging. May also roost in
caves, mines, hollow trees
and buildings.
15
Live Oak Associates, Inc. Barron Creek Biological Evaluation
PN 1435-01
San Francisco dusky -footed woodrat
CSC
Found in hardwood forests,
Unlikely. The riparian habitat on the
Neotoma fuscipes annectens
Federally Threatened
oak riparian and shrub
site lacks the dense shrub understory
FPE
Federally Endangered (Proposed)
habitats.
typically favored by this species. No
FC
Federal Candidate
CP
woodrat nests were observed on the
CSC
site.
American badger
CSC
Found in drier open stages
Absent. Suitable habitat for this
Taxidea taxus
Plants Presumed Extinct in California
of most shrub, forest and
species is absent from the site.
113
Plants Rare, Threatened, or Endangered in
herbaceous habitats with
information — a review list
California and elsewhere
friable soils.
Plants of limited distribution —a watch list
*Explanation of Occurrence Designations and Status Codes
Present: Species observed on the sites at time of field surveys or during recent past.
Likely:- Species -not -observed on the site; but it may reasonably be expected to occur there on a -regular basis.
Possible: Species not observed on the sites, but it could occur there from time to time.
Unlikely: Species not observed on the sites, and would not be expected to occur there except, perhaps, as a transient.
Absent: Species not observed on the sites, and precluded from occurring there because habitat requirements not met.
STATUS CODES
FE
Federally Endangered
CE
California Endangered
FT
Federally Threatened
CT
California Threatened
FPE
Federally Endangered (Proposed)
CR
California Rare
FC
Federal Candidate
CP
California Protected
CSC
California Species of Special Concern
CRPR
California Rare Plant Ranking
1A
Plants Presumed Extinct in California
3
Plants about which we need more
113
Plants Rare, Threatened, or Endangered in
information — a review list
California and elsewhere
4
Plants of limited distribution —a watch list
2
Plants Rare, Threatened, or Endangered in
California, but more common elsewhere
Live Oak Associates, Inc. Barron Creek Biological Evaluation
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2.4 JURISDICTIONAL WATERS
Jurisdictional waters include rivers, creeks, and drainages that have a defined bed and bank and
that, at the very least, carry ephemeral flows. Jurisdictional waters also include lakes, ponds,
reservoirs, and wetlands. Such waters may be subject to the regulatory authority of the U.S.
Army Corps of Engineers (USACE), the California Department of Fish and Game (CDFG), and
the California Regional Water Quality Control Board (RWQCB). See Section 3.2.4 of this
report for additional information.
The reach of Barron Creek occurring onsite has been channelized and straightened from its
original alignment, and it enters ,and exits the site via culverts. Barron Creek is presumed to be,
at the very least, a seasonal watercourse, as it has been observed to convey, water by LOA in
December 2009 and in June and August 2010. Water sources include natural runoff upstream of
the site. Additionally, several small pipes convey runoff from adjacent properties into the creek
at the upstream end of the site. The channel ranges from eight to eleven ft. wide at the ordinary
high water level.
A formal wetland delineation of the site was completed on August 4, 2010. The USACE issued
their jurisdictional determination on March 29, 2011, at which time they claimed jurisdiction
over the reach of the creek occurring onsite. The limit of USACE jurisdiction, as well as that of
the RWQCB, is the ordinary high water level. The creek is also subject to the jurisdiction of the
CDFG up to the top of bank or the edge of associated riparian vegetation, whichever is greater.
17
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3.0 IMPACTS AND MITIGATIONS
3.1 SIGNIFICANCE CRITERIA
Approval of general plans, area plans, and specific projects is subject to the provisions of the
California Environmental Quality Act (CEQA). The purpose of CEQA is to assess the impacts
of proposed projects on the environment before they are carried out. CEQA is concerned with
the significance of a proposed project's impacts. For example, a proposed development project
may require the removal of some or all of a site's existing vegetation. Animals associated with
this vegetation could be destroyed or displaced. Animals adapted to humans, roads, buildings,
pets, etc.-, may replace those species formerly occurring on the site. Plants and animals that are
state and/or federally listed as threatened or endangered may be destroyed or displaced.
Sensitive_habitats such as wetlands and riparian woodlands may be_altered.or destroyed -
Whenever possible, public agencies are required to avoid or minimize environmental impacts by
implementing practical alternatives or mitigation measures. According to Section 15382 of the
CEQA Guidelines, a significant effect on the environment means a "substantial, or potentially
substantial, adverse change in any of the physical conditions within the area affected by the
project, including land, air, water, minerals, flora, fauna, ambient noise, and objects of historic or
aesthetic interest."
Specific project impacts to biological resources may be considered "significant" if they would:
• Have a substantial adverse effect, either directly or through habitat modifications,
on any species identified as a candidate, sensitive, or special status species in
local or regional plans, policies, or regulations, or by the California Department of
Fish and Game or U.S. Fish and Wildlife Service;
• Have a substantial adverse effect on any riparian habitat or other sensitive natural
community identified in local or regional plans, policies, regulations or by the
California Department of Fish and Game or U.S. Fish and Wildlife Service;
• Have a substantial adverse effect on federally protected wetlands as defined by
Section 404 of the Clean Water Act (including, but not limited to, marsh, vernal
pool, coastal, etc.) through direct removal, filling, hydrological interruption, or
other means;
Live Oak Associates, Inc. Barron Creek Biological Evaluation
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• Interfere substantially with the movement of any native resident or migratory fish
or wildlife species or with established native resident or migratory wildlife
corridors, or impede the use of native wildlife nursery sites;
• Conflict with any local policies or ordinances protecting biological resources,
such as a tree preservation policy or ordinance; or
• Conflict with the provisions of an adopted Habitat. Conservation Plan, Natural
Community Conservation Plan, or other approved local, regional, or state habitat
conservation plan.
Furthermore, CEQA Guidelines Section 15065(a) states that a project may trigger the
requirement to make a "mandatory findings of significance" if the project has the potential to
Substantially degrade the quality of the environment, substantially reduce the
habitat of a fish or wildlife species, cause a fish or wildlife population to drop
below-self=sustaining-levels, -threaten.-to--eliminate a- plant _or--animal--community,_.__
reduce the number or restrict the range of an endangered, rare or threatened
species, or eliminate important examples of the major periods of California history
or prehistory.
3.2 RELEVANT GOALS, POLICIES, AND LAWS
3.2..1 Threatened and Endangered Species
State and federal "endangered species" legislation has provided the California Department of
Fish and Game (CDFG) and the U.S. Fish and Wildlife Service (USFWS) with a mechanism for
conserving and protecting plant and animal species of limited distribution and/or low or
declining populations. Species listed as threatened or endangered under provisions of the state
and federal endangered species acts, candidate species for such listing, state species of special
concern, and some plants listed as endangered by the California Native Plant Society are
collectively referred to as "species of special. status." Permits may be required from both the
CDFG and USFWS if activities associated with a proposed project will result in the "take" of a
listed species. "Take" is defined by the state of California as "to hunt, pursue, catch, capture, or
kill, or attempt to hunt, pursue, catch, capture or kill" (California Fish and Game Code, Section
86). "Take" is more broadly defined by the federal Endangered Species Act to include "harm"
(16 USC; Section 1532(19), 50 CFR, Section 17.3). Furthermore, the CDFG and the USFWS
are responding agencies under the California Environmental Quality Act (CEQA). Both
agencies review CEQA documents in order to determine the adequacy of their treatment of
endangered species issues and to make project -specific recommendations for their conservation.
Live Oak Associates, Inc. Barron Creek Biological Evaluation
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3.2.2 Migratory Birds
State and federal laws also protect most birds. The Federal Migratory Bird Treaty Act (16
U.S.C., scc. 703, Supp. I, 1989) prohibits killing, possessing, or trading in migratory birds,
except in accordance with regulations prescribed by the Secretary of the Interior. This act
encompasses whole birds, parts of birds, and bird nests and eggs.
3.2.3 Birds of Prey
Birds of prey are also protected in California under provisions of the State Fish and Game Code,
Section 3503.5, which states that it is "unlawful to take, possess, or destroy any birds in the order
Falconiformes or Strigiformes (birds of prey) or to take, possess, or destroy the nest or eggs of
any such bird except as otherwise provided by this code or any regulation adopted pursuant
thereto." Construction disturbance during the breeding season could result in the incidental loss
of fertile eggs or nestlings, or otherwise lead to nest abandonment. Disturbance that causes nest
abandonment and/or loss of reproductive effort is considered "taking" by the CDFG.
3.2.4 Wetlands and Other Jurisdictional Waters
Natural drainage channels and adjacent wetlands may be considered "Waters of the United
States" (hereafter referred to as "jurisdictional waters") subject to the jurisdiction of the U.S.
Army Corps of Engineers (USACE). The extent of jurisdiction has been defined in the Code of
Federal Regulations but has also been subject to interpretation of - the federal courts.
Jurisdictional waters generally include:
• All waters which are currently used, or were used in the past, or may be susceptible to
use in interstate or foreign commerce, including all waters which are subject to the
ebb and flow of the tide;
• All interstate waters including interstate wetlands:
• All other waters such as intrastate lakes, rivers, streams (including intermittent
streams), mudflats, sandflats, wetlands, sloughs, prairie potholes, wet meadows, playa
lakes, or natural ponds, the use, degradation or destruction of which could affect
interstate or foreign commerce;
• All impoundments of waters otherwise defined as waters of the United States under
the definition;
• Tributaries of waters identified in paragraphs (a)(l)-(4) (i.e. the bulleted items above).
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As recently determined by the United States Supreme Court in Solid Waste Agency of Northern
Cook County v. U.S. Army Corps of Engineers (the SWANCC decision), channels and wetlands
isolated from other jurisdictional waters cannot be considered jurisdictional on the basis of their
use, hypothetical or observed, by -migratory birds. However, the U.S Supreme Court decisions
Rapanos v. United States and Carabell v. U.S. Army Corps of Engineers (referred together as the
Rapanos decision) impose a "significant nexus" test for federal jurisdiction over wetlands. In
June 2007, the USACE and Environmental Protection Agency (EPA) established guidelines for
applying the significant nexus standard. This standard includes 1) a case-by-case analysis of the
flow characteristics and functions of the tributary or wetland to determine if they significantly
affect the chemical, physical, and biological integrity of downstream navigable waters and 2)
consideration of hydrologic and ecologic factors (EPA and USACE 2007).
The USACE regulates the filling or grading of such waters under the authority of Section 404 of
the Clean Water Act. The extent of jurisdiction within drainage channels is defined by "ordinary
high water marks" on opposing channel banks. Wetlands are habitats with soils that are
intermittently or permanently saturated, or inundated. The resulting anaerobic conditions select
for plant species known as hydrophytes that show a high degree of fidelity to such soils.
Wetlands are identified by the presence of hydrophytic vegetation, hydric soils (soils saturated
intermittently or permanently saturated by water), and wetland hydrology according to
methodologies outlined in the 1987 Corps of Engineers Wetlands Delineation Manual (USACE
1987).
All activities that involve the discharge of fill into jurisdictional waters are subject to the permit
requirements of the USACE (Wetland Training Institute, Inc. 1991). Such permits are typically
issued on the condition that the applicant agrees to provide mitigation that result in no net loss of
wetland functions or values. No permit can be issued until the Regional Water Quality Control
Board (RWQCB) issues a certification (or waiver of such certification) that the proposed activity
will meet state water quality standards. The filling of isolated wetlands, over which the USACE
has disclaimed jurisdiction under the SWANCC decision, is regulatedby the RWQCB. It is
unlawful to fill isolated wetlands without filing a Notice of Intent with the RWQCB. The
RWQCB is also responsible for enforcing National Pollution Discharge Elimination System
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(NPDES) permits, including the General Construction Activity Storm Water Permit. All projects
requiring federal money must also comply with Executive Order 11990 (Protection of Wetlands).
The California Department of Fish and Game has jurisdiction over the bed and bank of natural
drainages according to provisions of Section 1601 and 1602 of the California Fish and Game
Code (2011). Activities that would disturb these drainages are regulated by the CDFG via a
Streambed Alteration Agreement. Such an agreement typically stipulates that certain measures
will be implemented which protect the habitat values of the drainage in question.
3.2.5 Local Ordinances, Policies, and Habitat Conservation Plans
The Town's municipal code does not appear to contain any tree ordinances applicable to the type
of tree removal being proposed, and no other local ordinances or policies are known to be
applicable to the project. No known habitat conservation plans are in effect for this site.
3.3 IMPACTS AND MITIGATIONS SPECIFIC TO THE PROJECT SITE
The proposed project is for annual maintenance of approximately 624 linear feet of Barron Creek
to keep the creek clear of weeds and debris and to maintain an unobstructed flow of water
through the channel. Maintenance activities include the removal of up to nineteen willows at the
upstream end of the onsite channel, where debris currently accumulates,' and annual hand -
removal of weeds.
Any appreciable difference in either scope or general location of the proposed project would
require an additional impact assessment to ensure that unanticipated impacts to biotic resources
are not likely to occur.
3.3.1 Loss of Habitat for Special Status Plants
Potential Impacts. Thirteen special status vascular plant species are known to occur in the
general project vicinity (Table 1). Site development would have no effect on regional
populations of these species since the site provides no habitat for special status plants.
Therefore, state and federal laws protecting special status plants would not be relevant to
development of the site.
22
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Mitigation. Mitigation measures are not warranted.
3.3.2 Loss of Habitat for -Special Status Animals
Potential Impacts. Twenty special status animal species occur, or once occurred, regionally
(Table 1). With the exception of the yellow warbler, all of these species would-be absent from or
unlikely to occur on the site due to unsuitable habitat conditions. Proposed channel maintenance
activities would have no effect on these species or their breeding success because there is little or
no likelihood that they are present.
Yellow warblers may utilize the site for nesting (section 3.3.3): Project buildout would, at most,
-
---
result in a very small temporary reduction of foraging and/or breeding habitat available
regionally. The temporary loss of foraging or nesting habitat for this species would be
considered less than significant.
Mitigation. Mitigation measures are not warranted.
3.3.3 Disturbance to Active Raptor and Migratory Bird Nests
Potential Impacts. While no stick nests were observed in trees on the site during the August
2010 field survey, the willows occurring on the site and trees adjacent to the site provide
potential nesting habitat for tree -nesting raptors and other migratory birds, including yellow
warblers. If a raptor or migratory bird, regardless of its federal or state status, was to nest on or
adjacent to the site prior to or during proposed tree removal activities, such activities could result
in the abandonment of active nests or direct mortality to these birds: . Any activities that
adversely affect the nesting success of raptors or result in mortality of individual birds constitute
a violation of state and federal laws (sections 3.2.2 and 3.2.3) and would be considered a
significant impact under CEQA.
Mitigation. Trees planned for removal should be removed during the non -breeding season
(September 1 through January 31). If it is not possible to avoid tree removal during the breeding
season (February 1 through August 31), a qualified biologist should conduct a pre -disturbance
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survey for tree -nesting raptors and migratory birds in all trees planned for removal and
immediately adjacent to the disturbance zone no more than 30 days from the onset of the
removal activities, if such disturbance will occur during the breeding season. If nesting raptors
and migratory birds are detected on the site during the survey, a suitable activity -free buffer
should be established around all active nests. The precise dimension of the buffer (up to 250 ft.)
would be determined at that time and may vary depending on location and species. Buffers
should remain in place for the duration of the breeding season or until it has been confirmed by a
qualified biologist that all chicks have fledged and are independent of their parents. Pre -
disturbance surveys during the non -breeding season are not necessary for tree -nesting raptors and
migratory birds, as they are expected to abandon their roosts during disturbance activities.
Implementation of the above measures would mitigate impacts to tree -nesting raptors and
migratory birds to a less -than -significant level.
3.3.4 Disturbance to Waters of the United States or Riparian Habitats
Potential Impacts. Barron Creek is a water of the U.S. and California subject to regulation by
the USACE, RWQCB, and CDFG. Up to nineteen willows in the channel bed and along the
lower banks at the upstream end of the site will be removed, resulting in temporary disturbance
to approximately 175 linear ft. of waters of the U.S. Vegetation is expected to naturally recruit
from surrounding areas in a short amount of time to cover areas left barren as a result of the
willow removal. However, removal of the willows would be considered a significant impact.
Mitigation. The applicant is in the process of preparing a revegetation plan to compensate for
the loss of the removed willows. This mitigation is intended to ensure that the restoration
described in the project description will be implemented with suitable measures to offset this
impact. This mitigation was designed, in part, through informal conversations with the USACE
and CDFG and is conceptually consistent with their requirements (Paula Gill, pers. comm.,
February 2011; Dave Johnston, pers. comm., February 2011). The plan would need to be
approved by the responsible agency prior to the start of project activities. This measure would
compensate for the removal of the willows at a minimum 1:1 replacement -to -removal ratio along
the upper banks of the same reach of the creek where the willows are being removed. The
revegetation plan should:
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1. Designate suitable replanting areas.
2. Describe the -methods by which the revegetation will occur, including species
to be planted and plant installation guidelines.
3. Develop a timetable for implementation of the plan.
4. Outline a monitoring plan and establish appropriate performance criteria.
5. Describe remedial measures to be performed in the event that initial
revegetation measures are unsuccessful in meeting the performance criteria.
6. Describe site maintenance activities to follow revegetation activities. These
may include weed control, irrigation, and control of herbivory.
This measure will reduce impacts to a less -than -significant level.
--- __- -"Regulatory issues.---The-applicant--should--also comply -with all-state--and--federal--regulations--
related to work that will impact jurisdictional waters occurring on the site. This may require
obtaining a Section 404 Clean Water Act permit from the USACE, Section 401 Water Quality
Certification from the RWQCB, and Section 1600 Streambed Alteration Agreement from the
CDFG prior to initiating any maintenance activities within Barron Creek, if deemed necessary.
3.3.5 Loss of Habitat for Native Wildlife
Potential Impacts. Channel maintenance activities will include the removal of up to nineteen
willows currently along the bed and lower banks of the upstream portion of the site (section
3.3.4). However, an equivalent number of trees will be replanted along the upper banks of the
same reach of the creek. All other proposed activities would result in only temporary impacts to
the site. Vegetation that may be impacted would be expected. to naturally recruit in a short
period of time from surrounding areas. The site would be expected to return to its prior habitat
function and value. Therefore, the project would not result in.a permanent or significant loss of
habitat for native wildlife, nor would the project result in a wildlife population dropping below
self-sustaining levels or threaten to eliminate an animal community. The loss of habitat for
native wildlife resulting from the proposed project would constitute a less -than -significant
impact.
Mitigation. Mitigation measures are not warranted.
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3.3.6 Interference with the Movement of Native Wildlife
Potential Impacts. The reach of Barron Creek occurring onsite facilitates the movement of
wildlife through the site itself. However, the project site does not function as a wildlife
movement corridor because it is surrounded by development -and because the creek is below
ground immediately upstream and downstream of the site. Proposed channel maintenance
activities are not expected to have a significant effect on home range and dispersal movements of
native wildlife that may occur in the region. The proposed work may result in a temporary
disruption of local wildlife movements and would be expected to do so only during daylight
hours. Because the site will have functionally been unchanged once construction is complete,
these activities are not expected to result in any permanent or substantial changes in use or
movement patterns. Wildlife species presently utilizing this area are expected to continue
moving through it after maintenance activities have been completed. Therefore, the proposed
project would have a less -than -significant impact on corridor -type movements of native wildlife
within the region.
Mitigation. Mitigation measures are not warranted.
3.3.7 Degradation of Water Quality in Seasonal Drainages, Stock Ponds, and
Downstream Waters
Potential Impacts. Proposed channel maintenance activities will. result in a small area of soils
temporarily left barren in Barron Creek and, therefore, vulnerable to sheet, rill, or gully erosion.
Eroded and soils may be carried as sediment in surface runoff to be deposited in downstream
waters and adjacent wetlands. Furthermore, urban runoff is often polluted with grease, oil,
residues of pesticides and herbicides, heavy metals, and other pollutants, which may eventually
be carried to sensitive wetland habitats used by a diversity of native wildlife species.
The applicant is expected to comply with the provisions of applicable permits, including standard
erosion control measures that employ best management practices (BMPs). Compliance with the
above permit(s) should result in no impact to water quality in seasonal creeks, reservoirs, and
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downstream waters from the proposed project and should not result in the deposition of
pollutants and sediments in sensitive riparian and wetland habitats.
Mitigation. Mitigation measures are not warranted.
3.3.8 Local Ordinances or Habitat Conservation Plans
Potential Impacts. No local ordinances, HCPs, or NCCPs are known to be in effect for this
project. Therefore, the proposed project would not be impacted by any local policies related to
biological resources.
Mitigation. Mitigation measures are not warranted.
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REFERENCES
California Department of Fish and Game. 2011. California fish and game code. Gould
Publications. Binghamton, NY.
_. 2011. State and federally listed endangered and threatened animals of California.
The Resources Agency, Sacramento, CA.
_. 2011. California natural diversity database. The Resources Agency, Sacramento,
CA.
California Native Plant Society. 2011. Inventory of Rare and Endangered Vascular Plants of
California (7th Edition). Rare Plant Scientific Advisory Committee, David P. Tibor,
Convening Editor. California Native Plant Society. Sacramento, CA.
EPA and USACE. 2007. Clean Water Act Jurisdiction Following the U.S. Supreme Court's
Decision in Rapanos v. United States & Carabell v. United States. Environmental
Protection Agency and U.S. Army Corps of Engineers. Washington, D.C.
Natural Resource Conservation Service. 2010. Soil survey of Contra Costa County, California,
USDA. http://websoilsurvey.nres.usda.gov/app/WebSoilSurvey.aspx.
U.S. Corps of Engineers. 1987. Corps of Engineers wetlands delineation manual. Department
of the Army.
USACE. 2001. Minimum standards for acceptance of preliminary wetland delineations. U.S.
Army Corps of Engineers Regulatory Branch. November 30.
_. 2008. Regional Supplement to the Corps of Engineers Wetland Delineation Manual:
Arid West Region (Version 2.0). Engineer Research and Development Center.
U. S. Fish and Wildlife Service. 2011. Endangered and threatened wildlife and plants.
Wetland Training Insitute, Inc. 1991. Federal Wetland Regulation Reference Manual. B.N.
Goode and R.J. Pierce (eds.) WTI 90-1. 281pp.
Zeiner, David C., William F. Laudenslayer, Kenneth E. Mayer and Marshal White. Ed. 1988.
California's wildlife, volume I, amphibians and reptiles. Department of Fish and Game.
Sacramento, CA. 272 pp.
_. 1988. California's wildlife, volume II, birds. Department of Fish and Game.
Sacramento, CA. 731 pp.
_. 1988. California's wildlife, volume III, mammals. Department of Fish and Game.
Sacramento, CA. 407 pp.
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Personal Communications
Gill, Paula. February 22, 2011. U.S. Army Corps of Engineers.
Johnston, Dave. February 17; 2011. California Department of Fish and Game.
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APPENDIX A: VASCULAR PLANTS OF THE STUDY AREA
The plants species listed below were observed on the Barron Creek site during field surveys
conducted by Live Oak Associates in August 2010. The U.S. Fish and Wildlife Service wetland
indicator status of each plant has been shown following its common name.
OBL - Obligate
FACW - Facultative Wetland
FAC - Facultative
FACU - Facultative Upland
UPL - Upland
+/- - Higher/lower end of category
NR - No review
NA - No agreement
NI - No investigation
ANACARDIACEAE --Sumac Family
Rhus lancea*
African sumac
UPI,
APOCYNACEAE — Dogbane Family
Vinca major*
Greater periwinkle
UPI,
ASTERACEAE - Sunflower Family
Carduus pycnocephalus*
Italian thistle
UPI,
Helminthotheca echioides*
Bristly ox -tongue
FAC*
Lactuca serriola*
Prickly lettuce
FAC
CORNACEAE — Dogwood Family
Cornus sericea ssp. sericea
American dogwood
FACW
CUPRESSACEAE — Cypress Family
Cupressus sempervirens*
Italian cypress
NI
CYPERACEAE — Sedge Family
Cyperus eragrostis
Tall flatsedge
FACW
HAMAMELIDACEAE —
Liquidambar styraciflua*
American sweet gum
UPI,
LYTHRACEAE — Loosestrife Family
Lythrum hyssopifolium*
Hyssop loosestrife
FACW
MAGNOLIACEAE — Magnolia Family
Magnolia grandijlora*
Southern magnolia
-
MYRTACEAE — Myrtle Family
Lophostemon confertus*
Brisbane box
UPI,
ONAGRACEAE — Evening Primrose Family
Epilobium ciliatum ssp. ciliatum
Fringed willowherb
FACW
PLATANACEAE — Sycamore Family
Platanus racemosa
Western sycamore
FACW
POACEAE - Grass Family
Agrostis viridis*
Bentgrass
OBL
Paspalum dilatatum*
Dallis grass
FAC
Piptatherum miliaceum *
Smilo grass
UPI,
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Polypogon monspeliensis*
POLYGONACEAE — Buckwheat Family
Rumex crispus *
SALICACEAE — Willow Family
Populus nigra var. Italica*
Salix laevigata
Salix lasiandra ssp. lasiandra
Salix lasiolepis
SAPINDACEAE — Soapberry Family
Cupaniopsis anacardioides*
TAXODIACEAE — Bald Cypress Family
Sequoia sempervirens
TYPHACEAE — Cattail Family
Typha latifolia
VITACEAE — Grape Family
Vitis californica
* Introduced non-native species
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Rabbitsfoot grass
FACW
Curly dock
FACW-
Lombardy poplar
UPL
Red willow
UPL
Pacific willow
OBL
Arroyo willow
FACW
Carrot wood
UPL
Coast redwood
UPL
Broadleaf cattail
OBL
California wild grape
FACW
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