HomeMy WebLinkAboutResolution 29-26 w Exhibit AAdopted April 29, 2026
Land Use Element
Los Altos Hills General Plan
Page LU-1
LAND USE ELEMENT
INTRODUCTION
Purpose
101.Los Altos Hills is a residential community
nestled in the scenic foothills of the Santa Cruz
Mountains. Once a rural agricultural area, the
community has become one of the premier
residential areas in Silicon Valley. Over the
years, the population has grown and land use
patterns have changed. The farmhouses, cattle
ranches and orchards of the past have become
today’s private homes, riding stables and
vineyards. The community has gradually
urbanized over time but still retains a semi-rural
atmosphere, with large lots and expanses of
open space as envisioned by the Town’s founders.
102.Like their forefathers, today’s residents value the semi-rural character of the community.
Although it is nearly fully developed, the community is still evolving. The guiding
principle of the Land Use Element, as with other parts of the General Plan, is to address
long-term needs while preserving the semi-rural character of the community and the overall
quality of life for residents of Los Altos Hills.
Scope
103.This element addresses the factors that contribute to preserving community character
including the protection of its natural setting, the maintenance and improvement of its
residential neighborhoods, and the provision of quality public services and facilities. This
element also helps define the desired balance among the social, environmental and
economic costs and benefits associated with development.
Relationship to Other Elements
104.The Land Use Element is the keystone of the General Plan. It unifies the other elements by
providing an overall policy context. Many subjects reviewed here are discussed in greater
detail in other elements such as the Circulation & Scenic Roadways Element, the Pathways
Element, Housing Element, Conservation Element, and Open Space & Recreation
Element.
State Requirements
105.This element meets the State-mandated requirements for a Land Use Element. It defines
the Town’s land use categories and includes a Land Use Diagram that designates the land
use category of each parcel in the planning area. It also includes standards of population
density and building intensity for various land use categories. The Land Use Diagram and
the goals, policies and programs in this element will determine the location, intensity and
design of new development and ensure that the community’s semi-rural character is
maintained.
We want the sun and air
and quiet of a community
which has given itself
enough space to breathe
in; the relaxed pace of
country life and rural
pursuits.
From the Green Sheets published in 1956 prior
to the Town’s incorporation.
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LAND USE PATTERNS
History of Development
106.After World War II, the pressures of a growing population and increasing urbanization were
felt throughout the San Francisco Peninsula. Many members of the unincorporated Los
Altos Hills community viewed local commercialism as undesirable and felt threatened by
possible annexation by neighboring cities. When adjacent Los Altos incorporated in 1952
with a one-quarter-acre minimum lot size, residents of the Hills knew they had to take
action to defend and preserve the amenities of their rural life, such as one-acre lots and the
right to keep horses on private property.
107.The compelling reasons for the
incorporation of Los Altos Hills were
printed on green paper and distributed
to residents in the fall of 1955. As
stated in this document (referred to as
the “Green Sheets”) one of the primary
reasons the founders of the Town
originally decided to incorporate in
1956 was to maintain the rural
character of the community. This
desire continues today.
108.Existing Land Use
The Town is unique in that it consists
mainly of low-density single-family
residential development, with a
minimum lot size of at least one acre.
There are several limited areas recommended for multifamily use. There are no commercial
or industrial uses within the city limits. As the Town has developed over the past 50 years,
residents have continued to support the preservation of low-density residential
development and the semi-rural character of the community through one-acre zoning and
the protection of open space, creek corridors, wildlife habitat and heritage oak trees.
109.The only non-residential uses within the Town are open space, parks and recreation
facilities, a unique pathways system including miles of well-maintained roadside and
offroad paths, and public and private institutions such as schools, religious facilities and
governmental buildings.
Current Trends
110.With the exception of several small areas identified for future multifamily use, there is
limited land available for additional housing and only slight possibility of change on non -
residential parcels, Los Altos Hills is almost fully developed. However, in addition to infill
development on vacant lots, redevelopment is occurring as existing residences are torn
down and replaced with new homes and accessory dwelling units. The current trend is to
develop residences that maximize the square footage allowed under floor area and
development area regulations established by the Town’s Zoning Ordinance. Between 2017
and 2021, an average of 6 net new single-family homes were developed per year. Following
changes in State Housing Law, Los Altos Hills has seen dramatic growth in interest in and
production of accessory dwelling units (ADUs), averaging 20 per year between 2018 and
2022, increasing to an average of 30 ADUs per year between 2020 and 2024.
From the Green Sheets – 1956
What Kind of Community
Do We Want?
. . . a wide and not over-populated
community of homes in the country. . .
. . . the space and right to keep
animals—rabbits, chickens, dogs,
sheep, cattle and horses. . .
. . . roads that are content to remain
country lanes as long as they are
suitable for the residential traffic of
our area. . .
. . . at least one acre of land. . .
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Population Projections
111.In Projections 2007, the Association of Bay Area Governments (ABAG) forecasted that
the Town’s population within its corporate limits would increase from 8,500 in 2005 to
9,400 in 2035. The number of households was predicted to increase from 2,960 in 2005 to
3,300 in 2035 based on an average household size of 2.87 persons. As of the 2020 Census
Los Altos Hills had 3,016 households, the same population of nearly 8,500 persons, and a
declining average of 2.81 persons per household. ABAG projected a population of 8,600
for 2040. According to World Population Review, Los Altos Hills has an estimated 2025
population of 7,989, a declining at a rate of -1.24% annually and an estimated decline -
5.89% since the 2020 census. The addition of multifamily zones is expected to increase the
number of households by approximately 8 percent and counterbalance the declining
population.
Development Potential
112.A study of vacant and underutilized parcels conducted for
the 2002 Housing Element identified a total of 138 vacant
parcels with the potential to be subdivided. Based on the
size of the lots and known development constraints such
as steep slopes and open space designations, it was
estimated that approximately 58 to 176 additional units
could be developed through subdivision of these parcels.
At an average of 2.8 persons per household, development
of 176 additional units would result in a maximum
population increase of 493, putting the total population at
build-out at 9,100 compared to ABAG’s projection of
9,400 in 2035, but greater than ABAG’s revised projection
of 8,600 for 2040. Although additional households could
be accommodated through the development of secondary
units, it is not realistic to expect the Town’s population to
increase significantly beyond 9,000.
The multifamily designation allows approximately 375
multifamily homes. Multifamily units are much smaller
floor areas and fewer bedrooms than single-family homes
and have significantly smaller household sizes as a result.
Assuming a household size of 2.0 persons per unit the
multifamily zones could result in approximately 750
persons. At an unlikely average of 2.8 persons per multifamily household, the resulting
population could be as high as 1,050 persons. According to the 2020 Census, the total
population of Los Altos Hills was 8,489 persons. Therefore buildout of the new multifamily
zones could increase the population between 8 and 12 percent.
The Town’s
population is not
expected to increase
significantly due to
limited land available
for residential
development for
single-family
housing, and an
estimated 8% with
the addition of
multifamily zones.
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Implementing the General Plan
The Town’s Zoning Ordinance, Site Development
Ordinance and Subdivision Ordinance are the main
tools used to implement the General Plan. Supported
by administrative policies and procedures, the
ordinances establish processes for review and
approval of proposed land uses and regulation of site
development. The General Plan is also implemented
through specific programs that accompany the goals
and policies.
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GOAL 1
Maintain the semi-rural character of the community while providing for
residential uses, open space, and the minimum public and private facilities and
services needed to serve residents on a continuing basis.
Policy 1.1 Uses of land shall be consistent with the semi-rural atmosphere of the
community, minimize disturbance to natural terrain, minimize removal of
the natural vegetation, and create the maximum compatibility of
development with the natural environment through site design and
landscaping.
Policy 1.2 In addition to single-family residences, which may include secondary or
accessory dwelling units, uses within the planning area shall include:
a.Those uses normally accessory to dwellings in a semi-rural area:
vineyards and orchards, the keeping of horses and other domestic
animals, and other agricultural pursuits that are compatible with
residential uses;
b.Those open space preserves, parks and recreational uses necessary to
conveniently serve the residents;
c.Those public and private services and facilities including schools,
religious facilities, fire stations, and community centers needed locally to
serve Town residents;
d.Other uses required by State law including emergency shelters,
transitional housing, and single room occupancy units.
Policy 1.3 Large non-residential structures shall be compatible with the residential
character of the community.
Policy 1.4 Multifamily uses will be limited to areas with suitable access to collector and
arterial roads, freeway and expressway access, and on lands with contiguous
buildable areas excluding steep slopes to accommodate larger buildings and
development footprints, access to public sewer services and on or near non-
residential or institutional uses where possible.
Program 1.1 Establish and maintain zoning that allows and supports the development of single-
family and multifamily residences and accessory structures, as well as appropriate
non-residential uses.
Program 1.2 Continue to implement the Town’s Zoning Ordinance, Site Development
Ordinance, Subdivision Ordinance, and related policies and procedures. Review
and update these regulations as needed to ensure that development occurs in a
manner compatible with the Town’s semi-rural character and its natural
environment.
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Los Altos Hills General Plan
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LAND USE DESIGNATIONS
Land Use Diagram
113.The Town’s Land Use Diagram on the following page illustrates the community’s vision
for the development, redevelopment, and preservation of public and private properties in
the Los Altos Hills. The map designates the distribution and location of land to be used for
housing, open space, recreation, public facilities, and other uses. Each of the land use
categories designated on the Land Use Diagram is described below. The various land use
categories have been applied to geographic land areas within the community to indicate
which land uses the Town believes will be the most appropriate at that location.
Residential (R)
114.The predominant land use shown on the Land Use Diagram is residential. One single-
family dwelling is allowed per parcel. Accessory uses including one secondary dwelling
unit may be permitted. Agricultural activities and conditional uses such as religious
facilities and schools also may be allowed.
Multifamily Residential (MF)
115.The Multifamily Residential designation allows residential densities between 20 and 24
dwelling units per acre of contiguous buildable area exclusive of steep slopes over 25
percent. The maximum floor area of multifamily developments is limited to an average of
750 square feet of total floor area per dwelling unit and a mix of dwelling unit sizes based
on number of bedrooms. No single-family uses are permitted. Senior housing, assisted
living facilities, single-room occupancies, transitional and supportive housing, and
accessory dwelling units are also permitted.
Open Space Preserve (OSP)
115.This designation is applied to undeveloped, natural areas that provide wildlife habitat,
scenic views, and opportunities for nature study and low-impact outdoor recreation such
as hiking and horseback riding. The primary purpose of this designation is the preservation
and enhancement of the natural state of the land and its plants and animals. Allowable
development includes paths and trails, informational signs, restrooms, open fencing,
parking for the use of open space and Public Recreation Areas, and other incidental uses
that are consistent with the protection of open space and the enjoyment of low-impact
outdoor recreation.
Open Space Conservation Area (OSCA)
116.This is an overlay designation that is superimposed upon the residential land use areas on
the Land Use Diagram. The overlay is generally applied to areas of steep slopes, canyons
and ravines associated with major creeks or their tributaries, as well as creek corridors and
other areas of heavy vegetation that should be protected. Within these areas, special
measures should be taken to conserve the natural quality of the area and to avoid
environmental degradation. Residences should be placed on the most buildable portions of
lands designated OSCA and carefully sited so as to preserve existing trees, vegetation and
wildlife habitat.
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Public Recreation Area (RA-PB)
117.This designation identifies publicly owned open space lands used primarily for recreation.
Development related to recreation is allowed. Examples include Westwind Community
Barn, the Purissima Playing Fields (Little League Fields), and the Riding Arena.
Private Recreation Area (RA-PR)
118.This designation identifies privately owned lands used primarily for recreation.
Development related to recreation is allowed. An example is Fremont Hills Country Club.
Institutional (I)
119.This designation identifies academic, governmental and community service uses and lands
that are either publicly owned or operated by non-profit organizations. Examples are
schools, religious facilities, fire stations and Town government.
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DEVELOPMENT STANDARDS
State Requirements
120.State planning and zoning law requires the Land Use Element to include a statement of the
standards of population density and building intensity recommended for the planning area.
As used in this element, the term density refers to population and development capacity of
residential land. Density is described in terms of dwelling units per net acre of land and is
related to the average slope of the parcel or lot. The term intensity refers to the extent of
development on a parcel of land or lot (i.e., maximum development area). The Town’s
development standards for hillside protection, slope density, and other related concepts are
described below.
Hillside Protection
121.The rolling hills of Los Altos Hills are a highly valued natural feature of the community
that should be protected. The hillsides provide important wildlife habitat, recreational
opportunities, and scenic resources. Hillside areas are also subject to potential seismic
hazards, landslides, fires, and other environmental hazards that can create risks to public
safety, expose homeowners to potentially significant damage, and require extraordinary
expenditures for public services. It is important to provide safe residential development
while preserving the natural features, environmental integrity, and scenic character of the
hills.
122.Low-density residential development can be compatible with hillside protection, especially
where slopes are not excessively steep. Higher density and intensity multifamily housing
has larger buildings and larger development footprints than single-family homes.
Multifamily development needs larger contiguous areas for development without
significant environmental constraints, particularly areas without steep slopes. As discussed
in the USGS report in Appendix A, environmental concerns increase progressively as the
slope of the terrain increases. To the maximum extent feasible, steep slopes, canyons and
ravines, as well as natural swales and drainage channels, and geological hazard areas within
areas designated for residential development should be left undisturbed and preserved in
their natural condition.
Slope Density Standards for Subdivisions and Multifamily Development
123.Within those areas designated for low density residential use, net lot area should be not less
than one acre (43,560 square feet) per primary dwelling unit. In addition, the minimum net
lot area for subdivisions should increase with an increase in average slope, based on the
following slope-density standards for parcels designated for low density use:
Average slope of land
to be subdivided Minimum net lot size
0 – 10% slope One acre
10 – 50% slope An increase from one to seven
acres, based on the average
slope of the land.
Over 50% slope These areas generally should
not be developed for residential
purposes.
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Multifamily residential development shall be limited to areas with slopes of less than 25
percent. Limited disturbances to areas with slopes over 25 percent (e.g., not more than 10
percent of the contiguous building area exclusive of slopes greater than 25 percent) may
be permitted where necessary to provide access and overall design efficiency.
Lot Unit Factor
124.The lot unit factor (LUF) for any parcel designated for low density use is based on lot size
and average slope as determined by a formula established in the Town’s Zoning Ordinance.
Newly created lots must have a LUF of one or more. Some lots with a LUF of less than
one were created early in the Town’s history, prior to incorporation. These lots are
considered nonconforming and their development is restricted today. Lots with a LUF of
less than one may not be created today. Lots with a LUF of less than .50 require a
conditional development permit. Multifamily development shall be subject to a minimum
contiguous buildable area requirement (exclusive of steep slopes) instead of a LUF
calculation.
Maximum Floor Area and Maximum Development Area
125.Floor area is the total square footage of a structure as specified in the Town’s Zoning
Ordinance. Development area is the total floor area of a residence, plus the total area of a
parcel covered by other structures and hardscape not included in floor area. The maximum
floor area (MFA) and maximum development area (MDA) for a parcel designated for low
density use is based on the average slope and the Lot Unit Factor (LUF) as determined by
formulas established in the Zoning Ordinance.
The maximum floor area for parcels designated for multifamily development is calculated
by multiplying the maximum permitted average square feet of total floor area by the
number of permitted dwelling units.
In multifamily residential districts, parcels shall instead be subject to a Floor Area Ratio
(FAR) requirement for habitable floor area per acre of contiguous buildable area. The base
FAR shall be 0.45 in multifamily residential districts as set forth in the Zoning Ordinance.
Bonus FAR shall be available for senior and assisted living development projects and
affordable housing, as set forth in the Town’s Zoning Ordinance.
126.Building Setbacks
Setbacks regulate the placement of buildings with respect to their property lines in order to
provide a minimum amount of open space between buildings on adjacent parcels and
between buildings and street rights-of-way. Setbacks for single-family residences are
generally 40 feet from the front property line and 30 feet from the sides and rear property
lines. Increased setbacks are required for estate homes over 10,000 square feet in size.
Setbacks for multifamily residences are generally 3560 feet from the front, side, and rear
abutting single-family residential uses, and 25 10 and 20 feet respectively from side and
rear yards abutting non-residential or institutional uses.
Height Limits
127.The vertical height of buildings is limited to 27 feet for single-family residences in order
to maintain a consistent, low profile that is compatible with the Town’s semi -rural
character. Building height may be increased to a maximum of 32 feet if setbacks are
increased as specified in the Town’s Zoning Ordinance.
The vertical height of multi-family residences is limited to 32 feet, excluding basement and
underground parking where the exposed portions do not exceed 25% of the façade of the
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story above it, and excluding necessary rooftop mechanicals where less than 10% of the
roof area, and other architectural features.
Green Building
128.In response to growing concerns about rising energy costs and dwindling natural resources,
an increasing number of communities are embracing the concept of “green building.” This
whole-systems approach to homebuilding seeks to minimize the use of energy, water and
other natural resources and maximize the use of recycled and renewable construction
materials. The Town should develop programs and development standards regarding green
building practices such as the use of recycled and renewable construction materials,
energy-efficient heating and cooling systems, water conservation and reuse, and energy-
efficient appliances.
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Los Altos Hills General Plan
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GOAL 2
Ensure that all development occurs in a manner that
minimizes disturbance of natural terrain, vegetation and wildlife,
and maximizes the preservation of natural resources and open space.
Policy 2.1 Residential densities shall be guided by considerations of topography,
vegetative cover and significant physical limitations inherent in the natural
environment.
Policy 2.2 The minimum parcel size for single-family dwellings shall be at least one acre
and shall increase as the steepness of the land increases; and approximately
0.53.5 acres for multifamily development over 20 dwelling units per acre.
Policy 2.3 In subdividing land, the number of dwelling units permitted shall decrease
as the steepness of the land increases.
Policy 2.4 Steep slopes, canyons and ravines generally in excess of 30% slope, as well as
natural swales and drainage channels, and geologic hazard areas within
areas designated for residential development shall be left undisturbed and
preserved in their natural condition to the maximum extent feasible.
Policy 2.5 Limits on the development of individual residential lots shall be determined
based on evaluation of such factors as natural vegetation, topographic
characteristics, soils and geology.
Policy 2.6 The natural character of ridgelines shall be preserved to the maximum extent
feasible.
Policy 2.7 Promote the use of green building methods and practices in the planning,
design, construction, renovation, operations, and demolition of buildings.
Policy 2.8 The Town shall encourage the installation of drought-tolerant landscaping
and other methods of reducing water use for landscaping.
Program 2.1 Continue to require the dedication of open space easements where appropriate as
a condition of approval for new development. Each parcel shall be evaluated on a
case-by-case basis during the site development review process to determine
whether an open space easement should be required, based on the extent of steep
slopes generally in excess of 30% slope and the presence of heritage oak trees
and/or creek corridors. Other considerations shall include the size of the proposed
open space easement, its contiguity with existing open space easements, and
whether the property is located within an Open Space Conservation Area.
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Program 2.2 Limit grading on hillsides to the minimum extent necessary to accommodate
structures. Structures should be located so that they are consistent with slope
contours and compatible with the terrain.
Program 2.3 Encourage the preservation of existing trees, rock outcroppings, ridgelines and
other significant natural features.
Program 2.4 Encourage the preservation of native hillside vegetation and, if vegetation must
be removed, require appropriate revegetation and planting in hillside areas.
Program 2.5 Protect the public safety and minimize the risk of damage from natural hazards
by requiring site-specific geologic investigations of proposed building sites.
Program 2.6 Continue to require soil erosion control measures on construction sites and require
revegetation thereof.
Program 2.7 Make green building publications and other sources of information available to
applicants, architects, builders and other individuals involved in the construction
of new homes and major remodel projects.
Program 2.8 Consider developing a green building ordinance for site development and building
applications.
Program 2.9 Develop and implement a program for the reduction and recycling of construction
and demolition waste.
Open Space Easements
Open space easements (OSE’s) may be required as a
condition of approval for site development. When an OSE
is required, the property owner signs an agreement with
the Town to keep the easement area undeveloped and in
its natural condition. Once an OSE has been granted, the
property remains under private ownership; the OSE does
not give public access to the property.
See the Open Space & Recreation Element for additional
information on open space easements.
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COMMUNITY SERVICES AND FACILITIES
Public Schools
129.The Town is served by four public school districts:
•Los Altos School District (K-8)
•Palo Alto Unified School District (K-12)
•Mountain View−Los Altos Union High School District (9-12)
•Foothill Community College District
Historically, the majority of Town residents attending public elementary school were
enrolled at one of three public schools located within the planning area, all of which were
located west of Foothill Expressway. After elementary school, Town residents th en
matriculated to middle schools that were located in either Palo Alto or Los Altos. Students
then attended Gunn High School in Palo Alto or Los Altos High School or Mountain View
High School in Los Altos, based on attendance areas.
130.Over the past 25 years, in spite of significant opposition
from Town government and residents, the school districts
have closed all three elementary schools so that children
in the Town presently must commute to elementary
schools in either Palo Alto or Los Altos. All commutes,
by necessity, require the crossing of Foothill Expressway,
which is a heavily traveled, four-lane roadway. Due to
safety concerns and the long distances involved, few
elementary school children can walk to school. Many
parents, unhappy with this situation, would like to have
neighborhood schools reopened so their children can
walk to school. Bullis-Purissima School, closed in 2003,
is expected to be reopened in 2008. Recent cooperation
between the districts (such as Inter-District Transfer
Agreements) should be encouraged to allow children from both elementary districts to
attend the same neighborhood public elementary schools in Town.
131.There are three existing public school sites within the Town’s planning area. These sites
are owned by either Palo Alto Unified School District (PAUSD) or Los Altos School
District (LASD):
•26800 Fremont Road, formerly Fremont Hills Elementary School (PAUSD
property). The district closed the public school on this site in 1975 and signed
a long-term lease with Pinewood School, a private, non-denominational
school. The Town has some limited use of the athletic fields in the summer.
•25890 Fremont Road, Bullis Purissima Elementary School (LASD
property). The district closed the public elementary school on this site in 2003
despite substantial opposition from the Town government and residents. The
district presently is planning to reopen the renovated elementary school in
2008.
Neighborhood
schools are the basis
for a successful,
vibrant community
where neighbors
interact, establish
common bonds, and
provide a sense of
community for all.
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•11311 Mora Drive, Los Altos (LASD property). This site is located in
unincorporated area within the Town’s sphere of influence. The district has
closed the public elementary school and leased it to the Waldorf School, a
private school. The Town has no rights to use any of this property.
Town surveys indicate that residents view recreational fields and playgrounds at public and
private schools as an important community resource. The Town should work with school
districts to permit public use of these facilities.
132.The Town believes that it is extremely important for its residents to be able to send their
children to local elementary schools, with the majority of children having the ability to
walk or bicycle to school. This can be achieved by reopening public elementary schools on
the two sites noted above that are currently being leased to private institutions. Providing
public schools for kindergarten through grade 6 within the Town boundaries that primarily
serve Town residents is an integral part of imbuing the community spirit of our Town into
our children. Not only do neighborhood schools at this level promote the establishment of
lifelong friendships among the children, but they also encourage positive intercourse and
friendships among the parents. This is the absolute basis for all successful and vibrant
communities where neighbors interact, establish common bonds and provide a sense of
community for all.
133.The Town believes its residents are well served by the middle schools and high schools
operated by Los Altos School District, Mountain View−Los Altos Union High School
District, and Palo Alto Unified School District. These schools provide excellent educational
opportunities and extracurricular activities.
Foothill Community College
134.The Town is served by an excellent
community college in its midst,
Foothill Community College. Like
other public school districts, Foothill
College generally is not subject to the
Town’s zoning and site development
ordinances. However, the district is
required to obtain conditional use
permits for certain uses such as
wireless communication antennas. The
Town continues to work with the
Foothill College administration to
maximize the school’s benefits to
Town residents and minimize any
traffic impacts and disruptions
experienced by residents living near
the campus. The college is an
appropriate location for incorporation
of multifamily housing on
underutilized portions of the property
along with the continued use of the
property for educational institutional
uses. This can help meet the Town’s
housing needs and provide financial
Foothill Community College has
approximately 18,000 students.
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support for the continued use and
health of the college.
Private Schools
135.Private schools in the Los Altos Hills planning area include St. Nicholas School (K-8),
Pinewood High School and the Waldorf School. The latter two are located on public
school sites as discussed above. Like Foothill Community College, the St. Nicholas
School has been identified as an appropriate location for the addition of multifamily
housing on underutilized portions of the property.
Religious Facilities
136.Several religious facilities are located in the Los Altos
Hills planning area, including four that are located
within city limits:
•Poor Clare Monastery (Roman Catholic)
•Congregation Beth Am (Reform Jewish
Synagogue)
•Chapel in the Hills (Episcopal)
•Daughters of Charity (home for retired
Roman Catholic clergy)
All of these religious facilities hold conditional use
permits issued by the Town.
Town Government
137.The first Town Hall was built in the 1950’s on land
donated by the Town’s first Mayor, Arthur E. Fowle, at
the northeast corner of his 30-acre ranch at Fremont and
Concepcion Roads. The original facility served until
2004, when it was torn down because it no longer met
building codes, seismic requirements and accessibility
standards. It was replaced by a new energy efficient
facility that more than doubled the size of the original
building. Dedicated on June 16, 2005, the new facility
was designed to blend with the residential character of
the community. The new facility not only embodies the
rural aesthetic of the community, but also demonstrates
the Town’s commitment to energy and water
conservation.
138.Two other buildings in the Town Hall complex provide a
base for Town staff and services:
•Heritage House, which is a historic
house preserved by members of the
community. The building is used as the
Emergency Operations Center and
local office of the County Sheriff’s
Department.
Chapel in the Hills is in
the old Purissima School,
a historic building.
Energy-efficient Council Chambers
incorporate natural lighting.
Adopted April 29, 2026
Land Use Element
Los Altos Hills General Plan
Page LU-17
•The Parks and Recreation Center, located in the building formerly used by
Purissima Hills Water District.
Both buildings have recently been remodeled in
order to better meet the needs of the community. The Town’s corporation yard is located
on Purissima Road adjacent to the Purissima Playing Fields (Little League Fields). It serves
as the center for the Town’s maintenance crew and mechanical equipment.
Public Recreation Facilities
138.Town-owned parks and recreation facilities include Byrne
Preserve and six other open space preserves; Westwind
Community Barn; Purissima Playing Fields (Little
League Fields); the Riding Arena; and Edith Park. In
addition, the community’s extensive system of roadside
and off-road paths provides recreational opportunities.
Recreation programs sponsored by the Town include
youth camps, fitness programs and the annual Pathways
Run.
Private Recreation Facilities
139.Privately owned recreation facilities in the planning area
include Fremont Hills Country Club and several other
country clubs in neighboring cities, as well as Hidden
Villa, the Stanford University lands, and private boarding
stables.
Fire Protection
140.The Los Altos Hills County Fire Protection District is a
separate public agency, distinct from the Town, that
contracts with the Santa Clara County Fire Department
for the provision of fire protection, suppression and safety
services. The district owns and operates the El Monte Fire
Station near Foothill Community College.
Police Protection
141.The Town contracts with the Santa Clara County Sheriff’s
Department for police protection services. The Sheriff’s
Department typically provides one or two patrol cars at all
times, which is adequate because Los Altos Hills is a low-
crime community. In the event of emergencies, however,
the Town has access to the full resources of the County
Sheriff. The Town also has a public safety officer on staff
and provides a substation at the Heritage House next to
Town Hall for the use of the County Sheriff.
Parks and Recreation Center
is next to Town Hall.
Public and private
recreation facilities are
described in the Open
Space & Recreation
Element, which also
includes related goals,
policies and programs.
Fire and police
protection services are
described in the Safety
Element, which also
includes related goals,
policies and programs.
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Los Altos Hills General Plan
Page LU-18
Emergency Services
142.Ambulance and paramedic services are provided by Santa
Clara County on contract with the Los Altos Hills County
Fire District. In the event of a major disaster such as
earthquake or fire, emergency response services are
coordinated by the Town as established in the Emergency
Operations Plan. The Town’s Emergency Operations
Center (EOC) is located in the Heritage House adjacent to
Town Hall.
Emergency response
services are described
in the Safety Element,
which also includes
related goals, policies
and programs.
Adopted April 29, 2026
Land Use Element
Los Altos Hills General Plan
Page LU-19
GOAL 3
Encourage the development of community services and facilities that are easily
accessible, properly related to adjacent land uses, and in harmony with the semi-
rural, residential character of the community.
Policy 3.1 School districts shall be encouraged to restore neighborhood public
elementary schools in Los Altos Hills, particularly at the public school sites
listed in Paragraph 131.
Policy 3.2 The Town will encourage institutional uses that are necessary to serve local
residents, such as public schools, religious facilities, governmental buildings,
public recreational facilities and fire stations.
Policy 3.3 Major community facilities should be located where they can be served
directly by collector, or where possible, arterial roads so that they are
reasonably convenient to residents. The primary consideration should be
compatibility with adjacent land uses and with preserving the semi-rural,
residential character of the Town. However, given the lack of commercial
buildings and minimal number of institutions in the Town, some institutional
structures by necessity will be adjacent to residential properties.
Policy 3.4 Every effort should be made to ensure that recreational areas and playing
fields at both public and private schools are available for use by Town
residents during non-school hours.
Policy 3.5 School service areas should be defined so as to maximize the number of
children who can walk to schools within the Town borders, with particular
emphasis on the use of the Town pathway system, using both on-road and off-
road paths.
Policy 3.6 Public buildings should be of a size and scale conducive to maintaining the
semi-rural atmosphere of Los Altos Hills. The architectural design of non-
residential buildings should incorporate those principles that guide our
residential homes such as modest height and bulk appearance.
Program 3.1 Work with Palo Alto Unified School District and Los Altos School District to
reopen public elementary schools in Los Altos Hills.
Program 3.2 Cooperate with school districts in providing demographic data and other
information supporting the need for new schools.
Program 3.3 Continue to assist school districts by requiring the payment of school impact fees
as per Government Code Section 65995 prior to issuance of building permits.
Program 3.4 Explore innovative ways for the community to use school facilities and grounds
jointly with the school districts.
Adopted April 29, 2026
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Los Altos Hills General Plan
Page LU-20
Program 3.5 Work with school districts in the design and development of school facilities to
provide for community needs in the areas of parks and recreation, community
meetings, and similar activities.
Program 3.6 Work with school districts to minimize potential impacts on neighboring
residential areas.
Program 3.7 Continue to require conditional use permits for the location and operation of
private schools, religious facilities, and other institutional uses. Monitor and
mitigate potential impacts on neighboring residential areas by limiting the hours
of operation, the location of parking, and other factors as appropriate.
The Purissima Playing Fields, Town Riding Arena and Fremont Country Club
are in the foreground of this aerial photo looking northeast from Interstate 280
towards San Francisco Bay.
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Land Use Element
Los Altos Hills General Plan
Page LU-21
UTILITIES
Anticipated Needs
143.The Town is expected to experience very modest growth mostly through infill development
and redevelopment of underdeveloped parcels. As a result, the need for a full range of
public facilities and urban services is expected to grow very modestly in the fut ure. To
preserve the natural environment and semi-rural atmosphere desired by the residents of Los
Altos Hills, it is important that the installation and/or extension of utilities be conditioned
by concerns for preventing damage to the natural beauty and environmental integrity of the
area. Standards for the extension of utilities, sewers in particular, must be based on health
and safety considerations as well as environmental protection.
Water Supply
144.The Town’s drinking water is provided by two water suppliers: Purissima Hills Water
District and the California Water Service Company (Cal Water). As discussed in the
Conservation Element, the amount of water available is constrained. Purissima Hills
presently obtains all of its water from San Francisco’s Hetch Hetchy system and currently
is exceeding its supply assurance by 25-35 percent. Capacity limitations in the Hetch
Hetchy system may be reached in six to eight years, or sooner in times of drought. Cal
Water obtains the water supplied to Los Altos Hills from the
Santa Clara Valley Water District via pipelines from the Santa
Clara Valley Water District’s Rincoñada treatment plant and
from company-owned wells. During the dry season, the plant
and pipelines are at capacity. According to Purissima Hills Water
District, over two-thirds of the water used each year is for the
irrigation of landscaping.
Sanitary Sewer
145.There are more than 3,100 parcels within the Town, of which less than half are currently
connected to the municipal sanitary sewer system. The existing municipal system includes
approximately 52 miles of 6- to 12-inch diameter gravity pipelines, several reaches of force
mains, 1,305 manholes, and 2 lift stations. The Town straddles two drainage basins,
including the Palo Alto Basin to the north and the Los Altos Basin to the south. Sewage
collected by the Town’s existing system is conveyed to sewer trunk lines owned by the
cities of Los Altos and Palo Alto, with the portion of the Town in the Palo Alto Basin
draining into the City of Palo Alto municipal sewer system, and the Los Altos Basin
draining into the City of Los Altos municipal sewer system. The use of conveyance and
treatment systems owned by these cities is governed by separate service agreements with
the Town. The wastewater from all three communities eventually drains into the Palo Alto
wastewater treatment plant for treatment and disposal.
146.While there has always been sufficient capacity in the Palo Alto system to accommodate
all residences on the north side, the Town has been constrained by capacity limitations in
the Los Altos system. However, in 2007, the Town and the City of Los Altos signed a new
contract that provides additional capacity that will now allow all residences within
corporate limits of the Town and its sphere of influence to access sewers.
147.The Town prefers that as many residences as practicable connect to the sewer system.
While a properly constructed and maintained septic system typically does not present an
environmental hazard, the failure of a septic system can induce contaminants into t he
underground water table. Also, smaller lots may not be able to replace a failed system due
Water resources are
also discussed in the
Conservation Element,
which also includes
related goals, policies
and programs.
Adopted April 29, 2026
Land Use Element
Los Altos Hills General Plan
Page LU-22
to issues regarding the construction of a new leach field. The Santa Clara County Health
Department requires all new residences to connect to the sewer system if there is an existing
sewer main within 200 feet of the new residence.
148.All new residences resulting from new subdivisions and multifamily development should
be served by sanitary sewer trunk lines. All new residences resulting from the teardown of
an existing residence or a newly constructed home on an existing lot should be required to
connect to sanitary sewer trunk lines, provided there is an existin g trunk line within 200
feet of the new residence. Wherever the possibility of biological harm from septic tank use
exists, requirements for conversion to sanitary sewers should be established. Standards
should reflect Bay Area Water Quality Control Board and Santa Clara County Health
Department requirements.
149.The Town has appointed a committee to review the existing issues in regard to bringing
sewer mains to as many neighborhoods as possible. This committee has conducted a survey
among residents on septic tanks to determine the major issues that prevent these residents
from connecting to the system. Through various methods such as sewer reimbursement
districts, sewer assessment districts and the extension of sewer mains up main arteries to
make sewer connection more accessible, the Town hopes to significantly increase the
number of residences connected to the sewer system.
Storm Drainage System
150.The Town’s storm drainage system consists of a combination of roadside drainage ways,
cross culverts, and underground pipes. Stormwater in Los Altos Hills initially flows over
land, following the natural contours of the terrain and then moving to roadside flow routes.
Some of these are paved with asphalt concrete, but most roadside flow routes are dirt
ditches, which help preserve the natural, semi-rural feel of the community. Stormwater in
the roadside flow routes travels downhill to culverts, pipes or creeks that eventually carry
the storm runoff to the San Francisco Bay.
151.Silt and debris in the storm drain system sometimes cause water to back up and flood the
surrounding areas. The Town provides maintenance of the stormwater facilities in the
public right-of-way, including culverts crossing under public
roads and public roadside flow routes. This also includes areas
where the Town has permanent storm drain easements for public
drainage structures on private property. Although regular
maintenance helps prevent flooding problems, in some cases the
repair of deteriorated facilities and construction of new facilities
are needed to improve the storm drainage system.
152.The Storm Drainage Master Plan prepared in November 2004 identifies the location of
drainage problem areas in the Town and proposes solutions ranging from the installation
of new pipes and catch basins to the regrading of ditches and provision of riprap protection.
The Master Plan ranks the proposed projects in order of priority and estimates the costs
involved. Each year the Town adopts a Capital Improvement Program that includes some
of these projects and budgets for their completion.
Areas subject to
flooding are identified
on the map included in
Appendix B and
addressed in the
Safety Element.
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Land Use Element
Los Altos Hills General Plan
Page LU-23
153.The National Pollutant Discharge Elimination System (NPDES) permit program controls
water quality by regulating point sources of pollution, including municipal storm drain
systems, that discharge pollutants into surface waters. The Town is a co-permittee with
other members of a regional association known as the Santa Clara Valley Urban Runoff
Pollution Prevention Program (SCVURPPP), which shares a joint permit issued by the
Regional Quality Control Board to discharge stormwater into
the San Francisco Bay. The conditions of the permit require the
Town to reduce pollution in urban runoff to the maximum
extent possible. Recent changes strengthen the regulations for
projects that replace or create new impervious surface. The
permit must be reissued every five years. Policies and programs
related to stormwater quality are contained in the Conservation
Element.
Purissima Hills Water District
is a county special district
that provides water to many
residents of Los Altos Hills.
The district office is located
near Town Hall on Fremont
Road. Constructed in 2007,
the building was designed to
blend with the residential
character of the community.
PRIVATE UTILITIES
The following companies provide utilities
to residents of Los Altos Hills:
Cal Water Service Company Water
Pacific Gas & Electric (PG&E) Electrical power and gas
Comcast Cable TV and broadband
SBC Communications Local landline telephone and
DSL internet connections
Multiple providers Wireless telecommunication
Stormwater pollution is
also discussed in the
Conservation Element,
which includes related
goals, policies &
programs.
Adopted April 29, 2026
Land Use Element
Los Altos Hills General Plan
Page LU-24
Wireless Communication Facilities
154.The residents of Los Altos Hills depend on cell phones and other forms of wireless
communication services for convenience, business activities and security. As one of the
premier residential areas of the Silicon Valley, the Town should have a high level of
wireless service available to its residents in order to meet increasing demands for new and
better services. However, the Town’s topography, with its steep slopes and canyons, have
made cell phone reception problematic. To meet the demands for new and better services,
providers need an adequate number of wireless communication facilities in the planning
area.
155.The Town currently has 11 cell sites, each shared by multiple service providers who have
co-located antennas and equipment. Because the Town is entirely residential, with no
commercial or industrial areas, wireless
communication facilities are most appropriately
located on Town property or other public or
institutional sites such as schools and religious
facilities. The location of new facilities on or near
existing buildings, the co-location of antennas
owned by two or more companies, and landscape
screening should be utilized to minimize any
adverse visual impacts. To ensure that new facilities
are appropriately located, the Town has developed
policies and siting criteria for wireless
communication antennas and equipment shelters.
These policies and siting criteria should be
reviewed and updated as needed.
GOAL 4
Provide adequate, reliable utilities and urban services that will protect
the health and safety of all residents, while minimizing environmental
and aesthetic impacts on the community.
Policy 4.1 All utility installations shall be sited, designed, developed and landscaped so
as to blend with the natural character of the vicinity.
Policy 4.2 New and existing developments shall be adequately served by utilities and
infrastructure in accordance with Town standards. New projects that require
construction or expansion of public improvements shall pay their fair share
of the costs necessary to improve or expand infrastructure to serve them,
including street improvements, parks, pathways, sewer and water services,
storm drainage, and other urban services.
Policy 4.3 Power transmission lines, power distribution lines, and telephone lines
serving new development shall be placed underground.
The wireless communication facility
at Westwind Barn is designed to
blend in with the scenery.
Adopted April 29, 2026
Land Use Element
Los Altos Hills General Plan
Page LU-25
Policy 4.4 A systematic program for the undergrounding of all existing overhead lines
shall be developed and implemented.
Policy 4.5 All new residences and major additions shall be served by sanitary sewer
trunk lines or other disposal systems meeting adequate health standards.
Connection to sanitary sewer systems shall be required if available facilities
are within 200 feet.
Policy 4.6 The Town shall coordinate with the City of Los Altos and the City of Palo
Alto in the provision of sewer services to residents of Los Altos Hills.
Policy 4.7 New wireless communication facilities shall preferably be located on Town
property or other public or institutional sites such as schools and religious
facilities.
Policy 4.8 The co-location of wireless communication facilities with other facilities shall
be encouraged to the maximum extent feasible.
Policy 4.9 Wireless communication facilities shall be adequately screened by
landscaping in order to minimize any visual impacts.
Program 4.1 Prepare, adopt and implement an annual Capital Improvements Program
supporting policies in the General Plan to maintain, improve or expand public
utilities and infrastructure.
Program 4.2 Continue to require the payment of fees such as road impact fees, sewer hook-up
fees, and storm drainage fees for the costs of providing and maintaining public
utilities and infrastructure that serves new development.
Program 4.3 In coordination with the Santa Clara Valley Urban Runoff Pollution Prevention
Program, continue to implement measures consistent with the Santa Clara
Countywide NPDES Stormwater Permit.
Program 4.4 Continue to implement the Town’s policies and siting criteria for wireless
communications facilities, and review and update them as needed.
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Land Use Element
Los Altos Hills General Plan
Page LU-26
GROWTH BOUNDARIES
Sphere of Influence (SOI) Boundary
156.As required by state law, the Local Agency Formation Commission (LAFCO) has adopted
a sphere of influence (SOI) for each city and special district in Santa Clara County. The
SOIs are intended to ensure that urban development takes place in an orderly manner, to
preserve agricultural and open space lands, and to ensure that the land use and development
policies of a city are recognized in areas that will eventually be part of a city.
157.The SOI indicates areas that may be annexed to the Town and for which urban services, if
available, could be provided. The Town’s existing SOI, which was adopted in February
1985, is coterminous with the town limits to the north, west, and most of the east. The
boundaries of some of the Town’s unincorporated islands, unincorporated hillside lands,
lands within the Midpeninsula Regional Open Space District’s Rancho San Antonio Open
Space Preserve, and lands within the County of Santa Clara’s Rancho San Antonio Park
help form sections of the southern and southeastern portion of the Town’s SOI boundary.
Permanently preserved open space areas such as MROSD’s Rancho San Antonio Preserve
do not require urban services, but are appropriately included in the SO I due to their
location.
Unincorporated Pockets in Urban Serviced Area (USA)
158.The urbanized unincorporated areas within the Urban Service Areas (USA) of Los Altos
Hills are referred to as urban pockets or islands. The pockets are a result of development
that occurred in the County in the 1950s and 1960s. Santa Clara County and LAFCO have
adopted policies that state that urban islands and pockets should be annexed. There are
seven unincorporated urban pockets within the Los Altos Hills urban service area (USA).
Figure 1-2 shows current Town boundaries and urban pockets subject to future annexation
within the Town’s planning area.
Prezoning
159.The purpose of prezoning an area is to establish the zoning district that will apply in the
event of subsequent annexation to the Town. The proposed zones must be consistent with
the General Plan, and the prezoning has to be approved by the City Council at a public
hearing. There are two advantages to prezoning. First, the Town will have zoning in effect
immediately upon annexation. Local residents will thereby have prior knowledge of the
land use regulations that would affect them should annexation occur. Secondly, prezoning
acts to serve notice to LAFCO of the city's intentions regarding its adjacent areas.
Prezoning is the procedural first step necessary to ultimately annex a particular territory.
However, the act of prezoning does not compel the Town to initiate annexation
proceedings.
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Land Use Element
Los Altos Hills General Plan
Page LU-27
Definitions of Key Terms
Incorporated Town
Limits
Delineates lands currently within or annexed to the Town
Sphere of Influence
(SOI)
The probable physical boundaries and service area of the Town.
Inclusion of an area in the Town’s SOI is not necessarily an indication
that the area would be annexed to the Town or receive urban services.
Urban Service Area
(USA)
Delineates incorporated and unincorporated areas authorized to
receive urban services or proposed to receive urban services when
they are available.
Planning Area Encompasses incorporated and unincorporated territory that bears a
relation to the Town’s planning.
Adopted April 29, 2026
Land Use Element
Los Altos Hills General Plan
Page LU-28
160.In August 2002, the Town prezoned approximately 245 parcels in unincorporated county
lands known as San Antonio Hills. The prezoned area is generally between Ravensbury
Avenue and Interstate 280, including portions of West Loyola Drive, Mora Drive, and
Berkshire Drive. In March 2006, the Town prezoned an additional 82 parcels between
Magdalena and Eastbrook Avenues including properties on Spalding Avenue, Par Avenue,
Winding Way, Putter Avenue and Putter Way.
Annexation
161.Subsequent to the prezoning of San Antonio Hills in 2002, the Town annexed 118 parcels
totaling 142 acres within the unincorporated urban pocket. (Ravensbury Annexation,
March 2002; West Loyola Annexation, September 2007) The properties in the annexed
areas are mostly developed with single-family homes on parcels of one acre or more. There
remain approximately 280 acres of unincorporated land within the Town’s Urban Service
Area that may be subject to annexation in the future. The Town should conduct a
comprehensive evaluation of all future annexations to ensure that they are compatible with
the land use patterns and zoning designations of the Town and that such annexations do not
negatively impact the Town’s finances, facilities and services.
Areas of Direct Concern
162.Areas of Direct Concern are within the planning area but beyond the Town’s corporate
limits and the sphere of influence. These areas include several pockets of existing
residential and commercial/industrial development as described below:
Residential Areas
Portions of several residential areas in Los Altos and Santa Clara County are
included within the planning area. These areas, although in other jurisdictions, are
of direct and immediate concern to the planning area because of common problems
relating to drainage, circulation, public facilities, and visual amenities.
Existing development within the portion of Los Altos that is within the planning
area is low-to-medium density residential. Development of existing vacant land
immediately adjacent to Los Altos Hills should be no more intense than one -half
acre per dwelling unit in order to provide a gradual transition between residential
densities as previously agreed to by the City and the Town.
Commercial/Industrial Areas
The planning area includes commercial areas within the City of Los Altos and light
industrial development in the Stanford Industrial Park. These areas, however, do
not occur within the Town limits or its SOI.
Adopted April 29, 2026
Land Use Element
Los Altos Hills General Plan
Page LU-29
GOAL 5
Ensure that the Town’s growth will proceed in an orderly, planned manner
in order to provide efficient and economical urban services.
Policy 5.1 Issues within the sphere of influence shall be monitored for their effects on
the Town.
Policy 5.2 Any proposed annexations shall be consistent with the Town’s General Plan
land use designations and adopted annexation procedures.
Policy 5.3 Maintain a cooperative working relationship with Santa Clara County
regarding land use issues.
Program 5.1 Request that Santa Clara County and other applicable agencies refer all proposed
projects and programs within the sphere of influence to the Town of Los Altos
Hills for review and comment, and act favorably on the Town’s recommendations.
Program 5.2 Review annexation proposals to assure that they are consistent with sphere of
influence boundaries, General Plan land use designations and established
annexation procedures and criteria.
Program 5.3 In evaluating proposed annexations, require the preparation of a fiscal impact
analysis to determine the costs and benefits to be received by the Town as a result
of the proposed annexation.
Adopted April 29, 2026
Land Use Element
Los Altos Hills General Plan
Page LU-30
APPENDIX A
Excerpt of 2002 USGS Report by Suzanna K. Brooks,
Arthur H. Lachenbruch, and Carl M. Wentworth (2002)
Planning with Slope
Problems of regulating the creation of flat space and impermeable surface and their community impacts are
generally greater for steeper slopes (Nilsen and others, 1979, p.80). Whether such problems might require
regulation in any particular community depends upon the community’s physical setting and planning goals.
For the example of Los Altos Hills, Figure 3 shows that about one third of the community has slopes less
than 10%, a category in which experience has shown that grading, erosion, and other development alterations
to the natural terrain can generally be handled without difficulty (Mader and others, 1988).
According to Figure 3, almost half of the community has slopes from 10% to 30%, a slope category usually
targeted for residential development but with progressively increasing concerns and regulatory restrictions
toward the upper limit. In the one fifth of the town with slopes greater than 30% (Figure 3), residential
development without extensive modification of the surroundings becomes increasingly difficult, and much
of the land may be classified for limited uses with conservation easements, or with an open space designation.
Because slope is a fundamental physical parameter affecting land use in hillside communities, the community
general plan and many controlling ordinances (e.g. for grading, lot size, house size, development intensity,
foundation design, impermeable surface area, erosion control, and conservation easements) are often
formulated in terms of the slope of the land. The slope map (Figure 2) provides a useful means of viewing
the distribution of these potential problem areas, and of visualizing the community-wide implications of
various regulations proposed to deal with them.
Flat Space and Grading
Typically, to create a square one-acre flat pad with balanced amounts of cut and fill on a hillside where the
neutral slope is 20%, a total of two acres of natural terrain must be altered by grading (Figure 4) – the second
acre is occupied by the steep compensating cut and fill banks (typically 67% and 50% respectively). Similarly,
where the natural slope is 30%, about three acres must be graded to produce one flat acre (see dots, Figure
4A) – the remaining 2 acres are occupied by cut-and-fill banks that are roughly twice as steep as the original
surface. . . The graded cut-and-fill slopes are not only steeper than the natural surface, they are stripped of
existing trees and other vegetation; both factors can contribute to the instability and visibility of the graded
slope.
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