HomeMy WebLinkAbout3.1TOWN OF LOS -ALTOS HILLS
Staff Report to the Planning Commission
SUBJECT: A REQUEST FOR A SITE DEVELOPMENT PERMIT
NEW RESIDENCE WITH A BASEMENT, A DETAC
GRADING POLICY EXCEPTIONS; LANDS OF JA
26495 ALTAMONT ROAD; FILE #1-14-ZP-SD=GD
FROM: Nicole Horvitz, Assistant Planner
ITEM 3.1
June 5, 2014
FOR A TWO STORY
:HED BUNKER, AND
INVESTMENTS LLC;
APPROVED: Debbie Pedro, AICP, Community Development Director
RECOMMENDATION: That the Planning Commission:
Deny the requested Site Development Permit and Grading Policy exceptions based on the Findings
of Denial in attachment 1;
ALTERNATIVE
Offer the applicant the option to continue the project and return with a plan that conforms to the
Town's Grading Policy.
BACKGROUND
The subject property is located at the eastern side of Altamont Road. There is currently a 3,766
square foot single story residence built in 1969 on the 1.044 acre property. The surrounding uses
include one and two story single-family homes on adjacent parcels to the north, south, across
Altamont Road to the west and across Dezahara Way to'the east.
The applicant is requesting approval of a Site Development Permit to demolish the existing house
and construct a 4,987 square foot two story residence with a 4,859 square foot multi-level basement
and 1,499 square foot detached bunker.
CODE REQUIREMENTS
As required by Section 10-2.301 (c) of the Municipal Code, this application for a new residence
has been forwarded to the Planning Commission for review. The Zoning and Site Development
sections of the Municipal Code are used to evaluate proposed projects including floor and
development area limitations, grading, drainage, height, setbacks, visibility and parking
requirements.
In addition, pursuant to Section 10-1.202 of the Municipal Code this .application has been
forwarded to the Planning Commission for review because a bunker is proposed. "Bunkers which
are not located within the footprint of the building above, may be permitted by the Planning
Commission when it finds that such structures do not encroach in setbacks, are a minimum of
eighteen (1.8) inches below natural grade, are wholly underground except for required exiting,
Staff Report to the Planning Commission
Lands of Ja Investments_ LLC
26495 Altamont Road
June 5, 2014
Page 2 of 8 -
lighting and ventilation and are counted as development area except when placed under a surface
already counted as development area."
DISCUSSION
Site Data:
Net Lot Area: 1.044 acres
Average Slope: 19.10%
Lot Unit Factor: .0841
Floor Area and Development Area:
Area (sgft)
Maximum Existing
Proposed
Increase Remaining
Development
10,245* 10,605
10,039
-566 206
Floor -
5,000 3,766
4,987
1,221 13
Basement
- 0
(4,859)
(4,859) -
Bunker
- 0
(1,499)
(1,499) -
*Includes 500 sq.
ft. development area bonus per Section 10-1.502.b.6 (Solar
Ordinance)
Site and Architecture
The proposed project meets the setback, height, floor area,. and development area requirements
established in Title 10, Zoning and Site Development, of the Los Altos Hills Municipal Code.
The proposed two story residence with a basement and bunker is located a minimum of 47' from
the west (front) property line, 200' from the east (rear) property line, 35' from the north (side)
property line, and 57' from the south (side) . property line. The maximum building height on a
vertical plane is 27' and the maximum overall height of the building (including chimneys and
appurtenances) from the lowest point to the highest point is 27'. Proposed exterior materials consist
of a board form concrete fagade with a flat roof.
The lower floor of the residence consists of a total of 2,741 square feet with two (2)
bedroomsibathrooms, a library, and a tea room. The upper level has 2,246 square feet with an entry
way, living/dining area, kitchen, and library.
The 4,859 square foot basement is comprised of multi-level space consisting of an art collection
room, library, and storage rooms. The 1,499 square foot bunker contains a two (2) car garage and
storage room.
Driveway & Parking
The existing driveway along the north property line will be removed and replaced with a new
driveway that goes into the bunker garage along the south property line.
Pursuant to Section 10-1.601 of the Municipal Code, a total of four (4) parking spaces are required.
The proposed garage can accommodate two (2) cars and five (5) exterior parking spaces are
proposed above the proposed bunker.
Staff Report to the Planning Commission
Lands of Ja Investments LLC
26495 Altamont Road
June 5, 2014
Page 3 of 8
Outdoor Lighting
The applicant is proposing forty seven (47) shielded/down lights located on the exterior of the
residence and on the surrounding walls and steps. The applicant has submitted lighting
specifications indicating that all proposed fixtures will be either shielded, down lights, or have
frosted glass.
Trees & Landscaping
There are ten (10) trees proposed to be removed as apart of this application, including fruit, maple,
and a redwood tree. No heritage oaks are proposed to be removed with this application.
Drainage
Water runoff generated from the new development will be collected in to an 80' long 36" wide .
solid pipe detention system at the east side of the property, and then metered out though a 1.5"
wide pipe.
Pursuant to Section 10-2.503, Drainage Facilities Standards, of the Municipal Code, the
Engineering Department has reviewed and determined that the proposed drainage design complies
with Town requirements.
Grading Policy Exception
Total grading quantities for this project
include 5,450 cubic yards of cut for the
residence, basement, bunker, and yard areas.
Grading quantities for fill include 375 cubic
yards for the yard areas. The Engineering
Department has reviewed the proposed plans
and concluded that the proposed grading is
not in conformance with the Town's grading
policy.
The applicant is requesting a grading policy
exception for the residence and yard areas.
The Town's Grading Policy allows up to 8'
of cut for a house, excluding basements, and
4' of cut for driveway, parking, and yard areas.
® Up to 11'6"' of cut where 8 is
allowed for the house
® Up to 18"' of cut where 4 is
allowed for yard areas
Up to 18' of cut where 4 is
mo..
allowed
Up to 8'6' of cut where
4
- V
\
is allowed
Up to 11'6' of cut
(n es nce
e
- \
where 81s allowed
tt+'c4'
\(n)
lightwell \ti
i
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_— '\`
i
, :
�'
® Up to 11'6"' of cut where 8 is
allowed for the house
® Up to 18"' of cut where 4 is
allowed for yard areas
Staff Report to the Planning Commission
Lands of Ja Investments LLC
26495 Altamont Road
June 5, 2014
Page 4 of 8 .
Location
Grading Policy
Proposed
11'6 cut (house)
House with Basement
8' cut
32' cut. (basement)
43'6" overall
Yard Areas
4' cut
18' Cut
The purpose of the Town's Grading Policy is to assure that proposed construction retains the
existing site contours and landforms, to the greatest extent possible. It is also intended to provide
guidance for "stepping" structures down sloped hillsides and emphasizes cut to lower the profile
of structures over fill.
Staff has prepared Findings of Denial for the Grading Policy exceptions included in Attachment
1.
Basement and Bunker
The applicant is proposing a 4,859 square foot basement and 1,499 square foot detached bunker.
The proposed design of the basement is unique in that it is multi-level and necessitates a cut of up
to 43'6" deep. In addition, a 1,215 square foot light well with a 33'6" cut is proposed. The Town's
Grading Policy is intended to provide guidance for "stepping" structures down sloped hillsides.
The proposed residence and basement do not step with the site but is designed in a way that there
is a two story structure underground with an additional two story mass above, with an overall cut
of 43'6" from natural grade.
-
-=
.Lightwell ,
32' .
Basemedt
Staff Report to the Planning Commission
Lands of Ja Investments LLC
26495 Altamont Road
June 5, 2014
Page 5 of 8
The Los Altos Hills Municipal Code does not establish a maximum limit for basement excavation,
however, the General Plan Land Use Element and the Site Development Ordinance addresses
grading, siting, and disturbance to the site.
General Plan -Land Use Element
Policy 1. l- 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.
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.
Los Altos Hills Municipal Code
10-2.102 - The provisions of this chapter are adopted to permit reasonable development of land
while preserving the natural scenic character of the town, protecting the natural amenities, and
providing for the safety, benefit and welfare of its citizens by establishing minimum standards
and requirements relating to: (1) land grading, (2) drainage and erosion control, (3) the siting
of buildings and other development; (4) the planting of landscaping, (5) the installation of
driveways; (6) preservation of ridgelines; (7) the implementation and maintenance of the
Master Path Plan; and (8) outdoor lighting, and procedures by which such standards and
requirements may be enforced. It is intended that the provisions of this chapter be administered
with such purposes in mind.
• 10-2.401 - It is the purpose of this article to minimize erosion, soil compaction; topsoil
displacement, siltation of water courses, and other adverse effects of grading, including
alteration of the scenic qualities of the natural terrain. It is also the purpose of this article to
insure that at the completion of the project, the visible alteration of the natural terrain be
minimized,
• 10-2.702 (c) - The location of all structures should create as little disturbance as possible to the
natural landscape. The amount of grading, excavation, or fill shall be the minimum necessary
to accommodate proposed structures, unless grading is proposed to lower the profile of
buildings. Additional grading may be allowed for the purpose of lowering the profile of the
building provided that at the completion of the proj ect the visual alteration of the natural terrain
is minimized. The removal of vegetation and alteration of drainage patterns shall be the
minimum necessary to accommodate the proposed structure.
If the Commission decides to approve the project as proposed staff should be directed to prepare .
findings of approval for the Grading Policy exceptions and conditions of approval for the new
residence.
Staff Report to the Planning Commission
Lands of Ja Investments LLC
26495 Altamont Road
June 5, 2014
Page 6 of 8
Architectural Peer Review
As a part of the application process, the applicant agreed to have a peer review conducted by Town
consultant Duxbury Architects. In the report dated April 9, 2014 (Attachment 2), Peter Duxbury
states that the architecture of the new residence is consistent with the design guidelines of the Los
Altos Hills Fast Track Guide. In addition, the proposal "results in a lower profile than a more
conventional project stepping down the side and using retaining walls and grading." He believes
the project is a superior project as designed and recommends approval of the project as designed.
Neighbor Concerns
To date, staff has not received comments from the public.
Fire Department Review
The Santa Clara County Fire Department has reviewed the proposal and is requiring a sprinkler
system throughout all portions of the new the new residence. (Attachment 3)
Geotechnical Review
The Berrocal Fault runs along the west property line at a depth of approximately 5 to 10 feet below
the surface. Portions of the proposed bunker and lightwell are located within the fault zone. The
Town's geotechnical consultant Cotton, Shires & Associates, Inc. has reviewed the soil and
foundation report prepared by the project geotechnical consultant, and believes the proposed
"interstitial seismic buffer" (lightwell retaining wall) is intended to address potential future
earthquake ground motion. The project is designed to mitigate forces and deformations from the
fault. Cotton, Shires & Associates, Inc have recommended geological approval of the project.
(Attachment 4)
Committee Review
The Environmental Design and Protection Committee noted that this is a four story residence and
the extensive excavation will have a profound effect on the site. (Attachment 5)
The Pathways Committee recommends a type 2B pathway be constructed within the existing
pathway easement in the Altamont Road right of way. (Attachment 6)
Green Building Ordinance
This project is required to comply with the Town's Green Building Ordinance. The new residence
is designed to achieve 128 points in Build it Green's GreenPoint Rated program. .
CEQA STATUS
The project is categorically exempt under CEQA per Sections 15303 (a).
Staff Report to the Planning Commission
Lands of Ja Investments.LLC
26495 Altamont Road
June 5, 2014
Page 7 of 8.
ATTACHMENTS
1. Recommended Findings of Denial
2. Architectural Peer Review by Duxbury Architects dated April. 9, 2014
3. Recommendations from Santa Clara County Fire Department dated January 16, 2014.
4. Recommendations from Cotton, Shires and Associates, Inc dated March 27, 2014
5. Comments from Environmental Design and Protection Committee dated. January 17, 2014
6. Pathway Committee Meeting Minutes dated February 24, 2014
7. Worksheet #2
'8. Site Development Plans
Staff Report to the Planning Commission ATTACHMENT 1
Lands of Ja Investments LLC
26495 Altamont Road
June 5, 2014
Page 8 of 8'
ATTACHMENT 1
RECOMMENDED FINDINGS OF DENIAL FOR GRADING POLICY EXCEPTIONS
LANDS OF JA INVESTMENTS LLC, 26495 ALTAMONT ROAD
File # 1-14-ZP-SD-GD
The proposed grading is not in conformance with the General Plan Land Use Element
Policy 1.1 which states that "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". In addition, Program 2.2 of the
Land Use Element states that "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."
The requested grading exceptions exceed the minimum necessary to accommodate a new
residence. The total grading export quantity is 5,075 cubic yards. The subject property is
not unique in size or shape to prevent the design of a new residence and associated retaining
walls which would minimize disturbance to the natural terrain. The proposal exceeds the
minimum grading necessary in order to accommodate a new residence on this property.
The proposed cut for the multi-level basement and light well is up to 43'6".
2. The proposed grading exception is not consistent with Section 10-2.702 (c) of the Los Altos
Hills Municipal Code: "The location of all structures should create as little disturbance as
possible to the natural landscape. The amount of grading, excavation, or fill shall be the
minimum necessary to accommodate proposed structures, unless grading is proposed to
lower the profile of buildings. Additional grading may, be allowed for the purpose of
lowering the profile of the building provided that at the completion of the project the visual
alteration of the naturalterrain is minimized. The removal of vegetation and alteration of
drainage patterns shall be the minimum necessary to accommodate the proposed structure."
One of the reasons for the excessive. grading is to site the new residence at an elevation
where the multi-level basement will be exempt from floor area calculations, resulting in a
two story structure underground.
3. The proposed Grading Policy exceptions do not comply with the Town's Grading Policy
which is intended to provide guidance for "stepping" structures down sloped hillsides.
_D U X B U R Y A R C H I T E C T S
.............ATTACHMENT .2....:....... .
April 9, 2014
Debbie Pedro, Planning Director
The Town of Los Altos Hills
26379 Fremont Road
Los Altos Hills, CA 94022
Re: 26495 Altamont Road, Los Altos Hills, California
New House by: Lundberg Design
Dear Debbie,
I have reviewed the Architecture plans for 26495 Altamont Road, prepared by Lundberg
Design, dated 03/07/2014. 1 have met with the project architect at the site and viewed
the project architect's scale model of the project. I have visited the site once with the
project architect and twice independently.
The architecture for this project is very strong and appropriate for a hillside. The project
has a strong modernist approach with an interior light well. I believe this result creates
an architecture that is consistent with the Los Altos Hills Design Guidelines.
The house is a simple, elegant mass with flat roofs and an interior light well that is
embedded into the site, instead of a more conventional house stepping -down the site as
encouraged by the Design Guidelines and Grading Policy. The architect has taken great
care in working with and understanding the Planning Code, Grading Policy and the
Design Guidelines.
Geometry and Site -
A simple mass geometry, set into the site, results in a lower. profile than a more .
conventional project stepping down the site and using retaining walls and grading. This
elegant mass is set into the site with very little change to the existing adjacent grades.
The simplicity of the geometry, flat garden roof and interior light well allows this projedt
to be less visible from off site. The nature of the geometry set into the site allows the
north, east, south and west elevations to seem lower in profile. A good .portion of .the
Floor Area is at or below the existing natural grade line.
y'.
Cc: Nicole Horvitz, Assistant Planner
The use of a flat roof allows the property to have an overall lower geometry, in particular
from the Altamont and Julietta vantage points. The flat roof close to Altamont is well
below the 27'-0" line. Since Altamont and Julietta are higher in elevation, you are
looking down on and "over" the roof, which is a garden planted roof that will blend into
the adjacent rolling hills. The geometry of the overhangs and deck facing north and
east will cast shadows, which will help this project integrate with the existing
topography.
Interior Light Well
The interior light well is an extension and part of the basement. Basements require light,
ventilation and egress, usually and best provided by a light well. The advantage on this
project, the light -well is fully an interior space or basement. This project is designed so
that there are no visible vertical cuts, high retaining walls, or any offsite intrusion to the
natural topography. This light well provides natural light and egress and is completely
inboard and creates no artificial grade cuts or inconsistencies with the current Planning
Code.
The light well is a clever and important way of detaching the bunker garage and entry
hardscape from the main house and from the seismic fault that has been identified with
this property. By disengaging these two items and only connecting them by a bridge, or
"simple expansion joint", it creates a much safer, smart solution that is part of the
architecture.
Garage Bunkers/Access
I will let the engineers and the planners work out the definition of a bunker with the
solution presented by Lundberg Design. I believe the new garage, bunker and entry
design is a more consistent and fluid design solution with more planting than what is
currently there. The entry and car court design solution, along with the flat roof, makes a
much more appealing and natural look from offsite then the existing awkward cut
driveway and garage solution currently at the existing house.
Construction Operations/Excavation/Export
I believe the project design and construction team is fully experienced in projects such
as this and is fully capable of managing and executing this construction project to the
performance specifications and requirements of the Engineering and Planning staff. The
General Contractor will need to prepare a detailed Construction Operations Plan and
carefully comply with all the requirements as to grading, site preparation, erosion control
and the scheduling of construction traffic.
Overall, I think this is a superior project and I believe the design should be approved as
designed.
Cc: Nicole Horvitz, Assistant Planner
It is my opinion that the Engineering and Planning staff, the Planning Commission and
the City Counsel will see more designs like 26495 Altamont Road. Today, there is a
strong interest in developing "Important Architecture". I believe the Los Altos Hills
community should embrace innovative architecture and help Owners and Architects
create great architecture that I believe will blend and integrate into the existing Los Altos
Hills topography.
Peter H. Duxbury, AIA, NCARB, C-12811
Cc: Nicole Horvitz, Assistant Planner
C1,ARlq O� ',
FIDE DEPARTMENT ATTACH . 3
Ta'T7? 7; P��A SANTA CL.ARA COUNTY .,,�
14700 Winchester Blvd., Los Gatos, CA 95032-1818
(408) 378-4010 • (408) 378-9342 (fax) • www.sccfd.org
PLAN REVIEW No. 4 po54
BLDG
DEVELOPMENTAL REVIEW COMMENTS PERMIT No. n
.Proposed 11,630 square -foot two-story single-family residence with basement, decks and attached
;garage. JA IV
2241 .
Comment #1: Review of this Developmental proposal is limited to acceptability ofs 99,Ver and
water supply as they pertain to fire department operations, and shall not be construed asaHES
substitute for formal plan review to determine compliance with adopted model codes. Prior to
performing any work the applicant shall make application to, and receive from, the Building
Department all applicable construction permits.
Comment #2: Wildland-Urban Interface: This project is located within the designated Wildland-
Urban Interface Fire Area. The building construction shall comply with the provisions of California
Building Code (CBC) Chapter 7A. Note that vegetation clearance shall be in compliance with CBC
.Section 701A.3.2.4 prior to project final approval. Check with the Planning Department for related
.landscape plan requirements.
Comment #3: Fire Sprinklers Required: An automatic residential fire sprinkler system shall be
;installed in one- and two-family dwellings as follows: In all new one- and two-family dwellings and
;in existing one- and two-family dwellings when additions are made that increase the building area to
more than 3,600 square feet. Exception: A one-time addition to an existing building that does not
.total more than 1,000 square feet of building area. NOTE: The owner(s), occupant(s) and any contractor(s)
or subcontractor(s) are responsible for consulting with the water purveyor of record in order to determine if any
:modification or upgrade of the existing water service is required. NOTE: Covered porches, patios, balconies,
.and attic spaces may require fire sprinkler coverage. For buildings in excess of 6200 square feet, the (4) four most
hydraulically demanding heads in a room or compartment shall be calculated. Fire Department Connection:
For buildings in excess of 6200 square feet, a fire department connection (FDC) shall be provided. The FDC shall
consist of at least one 2.5" hose connection that is connected to the sprinkler riser with a pipe not less than the
diameter of the sprinkler riser. A State of California licensed (C-16) Fire Protection Contractor shall submit
plans,calculations, a completed permit application and appropriate fees to this department for -review and
approval prior to beginning their work. Section R313.2 as adopted and amended by LAHTC
City PLANS SPECS NEW RMDL AS
OCCUPANCY
CONST. TYPE
AppllcantName
DATE IPAGE
LAH
® ❑ ®
❑ ❑
SFR
V -B
Lundberg 01/16/2014
1 oF[i 2:]
SEC/FLOOR
AREA
LOAD
PROJECT DESCRIPTION
PROJECT TYPE OR SYSTEM
2 stry +
11630
Residential Development
Design Review
NAME OF PROJECT
LOCATION
SFR -
26495 Altamont Rd
Los Altos Hills
TABULAR FIRE FLOW
3000
REDUCTION FOR FIRE SPRINKLERS
REQUIRED FIRE FLOW Q 20 PSI
1500
BY
Harding, Doug
50 0
Organized as the Santa Clara County Central Fire Protection District
Serving Santa Clara County and the communities o/ Campbell, Cupertino, Los Altos,
Los Altos Hills, Los Gatos, Monte Sereno, and Saratoga
rLAR'A �,
41th-.1-4
/ or'
VT1? T v
FIDE DEPARTMENT
SANTA CLARA COUNTY
14700 Winchester Blvd., Los Gatos, CA 95032-1818
(408) 378-4010 •(408) 378-9342 (fax) • www.sccfd.org
DEVELOPMENTAL REVIEW COMMENTS
PLAN
REVIEW No.
14 054
BLDG
AppllcantName
PERMIT No.
PAGE
2 of 2
Comment #4: Water Supply Requirements: Potable water supplies shall be protected from
contamination caused by fire protection water supplies. It is the responsibility of the applicant and
any contractors and subcontractors to contact the water purveyor supplying the site of such project,
and to comply with the requirements of that purveyor. Such requirements shall be incorporated into
the design of any water-based fire protection systems, and/or fire suppression water supply systems
or storage containers that may be physically connected in any manner to an appliance capable of
causing contamination of the potable water supply of the purveyor of record. Final approval of the
system(s) under consideration will not be granted by this office until compliance with the
requirements of the water purveyor of record are documented by that purveyor as having been met
by the applicant(s). 2010 CFC Sec. 903.3.5 and Health and Safety Code 13114.7
Comment #5: Construction Site Fire Safety: All construction sites must comply with applicable
provisions of the CFC Chapter 33 and our Standard Detail and Specification SI -7. Provide
appropriate notations on subsequent plan submittals, as appropriate to the project. CFC Chp. 33
Comment #6: Premises Identification: Approved numbers or addresses shall be placed on all new
and existing buildings in such a position as to be plainly visible and legible from the street or road
fronting the property. Numbers shall contrast with their background. CFC Sec. 505
Plans not approved. To prevent plan review and inspection delays, the above noted Developmental Review
Conditions shall be addressed as "notes" on all pending and future plan submittals and any referenced
:diagrams to be reproduced onto the future plan submittal.
City PLANS SPECS NEW RMDL AS
LAH ® ❑ ® ❑ ❑
OCCUPANCY
SFR
CONST. TYPE
V -B
AppllcantName
DATE
Lundberg 01/16/2014
PAGE
2 of 2
SECIFLOOR
2 stry +
AREA
11630
LOAD
PROJECT DESCRIPTION
Residential Development
PROJECT TYPE OR SYSTEM
Design Review
NAME OF PROJECT
SFR -
LOCATION
26495 Altamont Rd
Los Altos Hills
TABULAR FIRE FLOW
3000
REDUCTION FOR FIRE SPRINKLERS
REQUIRED FIRE FLOW @ 20 PSI
1500
BY
Harding, Doug
1 5070 .
Organized as the Santa Clara County Central Fire Protection District
Serving Santa Clara County and the communities o/ Campbell, Cupertino, Los Altos,
Los Altos Hills, Los Gatos, Monte Sereno, and Saratoga
COTTON, SHIRES ANASSOCIATES, INC. ATTACHMENT 4
D
CONSULTING ENGINEERS AND GEOLOGISTS
TO: Nicole Horvitz
Assistant Planner
TOWN OF LOS ALTOS HILLS
26379 Fremont Road
Los Altos Hills, California 94022
March 27, 2014
L5163A
WEND
MAR 2 8 2014
TOWN OF LOS ALTOS HILLS
SUBJECT: Geotechnical Peer Review,
RE: Jayco Investments LLC, Guest House and Bunker
#1-14-ZP-SD-GD Revision
26495 Altamont Road
At your request, we have completed a geotechnical peer review of the site
develop and planning permit applications using:
• Preliminary. Plan Review_ &, Response to " Review Comments
(letter) prepared by Murray Engineers, Inc., dated February 28,
2014;
• Engineering Geologic and Geotechnical Investigation (report)
prepared by Murray Engineers, Inc., dated December 19, 2013;
• Civil Plans (7 sheets, various scales) prepare_ d by Lea & Braze
Engineering, revised March 6, 2014; and
Architectural Plans (22 sheets, various scales) prepared by
Lundberg Design, dated March 7, 2014.
In addition, we have reviewed pertinent documents and maps from our office
files and been in communication with the Project Geotechnical Consultant.
DISCUSSION
Based on our review of the referenced documents,. we understand that the
applicant proposes to demolish the existing residence at' the subject property and
construct a new guest house (with basement), and a separate garage/storage bunker.
Northern California Office Central California Office Southern California Office
330 Village Lane 6417 Dogtown Road 550 St. Charles Drive, Suite 108
Los Gatos, CA 95030-7218 San Andreas, CA 95249-9640 Thousand Oaks, CA 91360-3995
(408) 354-5542 • Fax (408),354-1852 (209) 736-4252 • Fax (209) 736-1212 (805) 497-7999 • Fax (805) 497-7933
www.cottonshires.com
Nicole Horvitz. March 27, 2014
Page 2 L5163A
The two structures.are to be connected by a bridge located 20 feet above a light well
between the two buildings. The proposed garage/storage bunker has been revised from
the previous design to be a single -story structure with open-air parking above.
The proposed design includes an "interstitial seismic buffer' intended .to
address potential future earthquake ground motion induced forces from the adjacent
Berrocal Fault. This fault is locally inclined in a southwesterly direction forming an
angle of approximately 12 degrees from horizontal. Planned project excavations will
remove shallow portions of the upper fault plane. Project design measures are proposed
to mitigate forces and deformations from the fault (as described below).
RECENT GEOTECHNICAL EVALUATIONS
We understand that the Project Geotechnical Consultant has worked with the
Project Architect to develop a method for mitigation of potential forces and deformations
along the Berrocal Fault. The excavations for the proposed project will remove a portion
of the existing fault trace and associated fault plane that descends into the ground to the
southwest.
Collected geologic data indicates that the fault plane is at a depth of
approximately 5 to 10 feet below the ground surface along the proposed western side of
the bunker. Approximate 10 -foot wide blocks of compressible foam are proposed to be
placed between the western bunker wall and the fault plane. Potential future forces/
displacement along the fault plane (estimated to be several inches to a few feet) is
anticipated to crush a portion of the foam without substantial adverse impacts to the
bunker structure or guest house. Murray Engineers have concluded that the proposed
innovative design is feasible from a geotechnical perspective.
CONCU-TSIONS AND RECOMMENDED ACTION
Proposed project construction is constrained- by the coincident location of the
Berrocal Fault, potential impact forces and displacements along the fault plane, seismic
ground shaking, and proposed deep project excavations. The Project Geotechnical
Consultant has recommended design measures to mitigate potential structural damage
associated with impact forces and displacement along the Berrocal Fault: In addition, the
Consultant has recommended sequenced excavation and top-down, staged construction of
retaining walls. Recommended construction methods should significantly reduce the
potential for instability of construction excavations.
COTTON, SHIRES AND ASSOCIATES, INC.
Nicole Horvitz
Page 3
March 27, 2014
L5163A
Based on our review of referenced documents, we conclude that proposed design
measures are feasible from a geotechnical perspective. We do not have geotechnical
objections to proposed design measures to mitigate potential impact forces and
displacement along the Berrocal Fault. We also do not have geotechnical objections to
the proposed site development layout or: issuance of permits for project grading. We
recommend that the following conditions. be attached to the project:
1. Geotechnical Plan Review - The applicant's geotechnical
consultant should review and approve all geotechnical aspects of
the project building and grading plans (i.e., site preparation and
grading, site drainage improvements and design parameters for
foundations, retaining walls and driveway) to ensure that their
recommendations have been properly incorporated.
The results .of the plan review should be summarized by the
geotechnical. consultant in a letter and submitted to the Town
Engineer for review and approval prior to issuance of building
permits.
2. Geotechnical Construction Inspections - The geotechnical
consultant should inspect, test (as needed), and approve all
geotechnical aspects of the project construction. The inspections
should include, but not necessarily be limited to: site preparation
and grading, site surface and subsurface drainage improvements,
and excavations for foundations and retaining walls prior to the
placement of steel and concrete. Encountered fault locations
should be documented (and photographed) and . adequate
positioning of compressible materials should be confirmed.
The results of these inspections and the as -built conditions of the
project should be described by the geotechnical consultant in a
letter and submitted to the Town Engineer for review prior to
final . (granting of occupancy) project approval. Construction
observation information about the determined fault position
should be kept with the parcel file.
LIMITATIONS
This geotechnical peer review has been performed to provide technical advice to
assist the Town with its discretionary permit decisions. Our services have been limited
to review of the documents previously identified, and a visual review .of .the property.
Our opinions and conclusions are made in accordance with generally accepted
COTTON, SHIRES AND ASSOCIATES, INC.
Nicole Horvitz
Page 4
March 27, 2014
L5163A
principles and practices of the geotechnical profession. This warranty is in lieu of all
other warranties; either expressed or implied.
TS:DTS:kd
Respectfully submitted,
COTTON, SHIRES AND ASSOCIATES, INC.
TOWN GEOTECHNICAL CONSULTANT
Ted Sayre
Principal Engineering Geologist
CEG 1795
1,
David T. Schrier
Principal Geotechnical Engineer
GE 2334
COTTON, SHIRES AND ASSOCIATES, INC.
m
ATTACHMENT 5 ^ OQ,.
RECMW
ENVIRONMENTAL DESIGN and PROTECTION COMMIT W014
=N QF HILLS
AQplicatian for:
,82plicant Name.
. . ...........
C)
7'N
Applicant Address:
Reviewed b
Date:
COMMENTS
Site Impact.
cy
77
.. ...... . ....fr
J: ...... . .. ..... . ... ..... .......
............. .. . . .. ... ....... .......
Creeks
Drains e'
....... . .............
Easements
. . ..... . .....
,�n�—Netiqtlon
Mitigation
. ...........................
. .............
_..._»—_..__.
. ..... . ............
. ........... .................... ...................... ...... ....... . ............... . ....... . ....
I
ATTACHMENT 6
Los Altos Hills Pathway Committee FINAL APPROVED
Minutes of Regular Meeting of Monday, February 24,2014
1. ADMINISTRATIVE
Chairman Joe Kleitman called the meeting to order at 7:03 PM
Members present: Weegie Caughlan, Ann Duwe, Nick Dunckel, Eileen Gibbons, Vic Hesterman, Breene
Kerr, Rachelle Mirkin, Tim Warner, Sue Welch, Denise Williams
Members/Associates absent: Tim Warner (excused); Bob Stutz (Associate member; excused)
Council Members present: Courtney Corrigan (PWC Council Liaison).
Members of public present: Bill Balson (Dori Lane)
The agenda was unanimously approved as written.
2. APPROVAL OF MINUTES
Minutes from the January 27, 2014 meeting were approved without -amendments.
3. Properties for Review. The following properties were reviewed for pathway recommendations:
A. 12501 Zappettini Court (File 12-14-ZP-SD-GD). Reason for pathway review is construction of a new
residence. The developer was not present. The parcel is on the west side of Zappettini Court at the
intersection with Altamont Road and has frontage on both roads. Altamont is a "two-sided" public road
designated by Council as a road for which roadside paths on both sides are recommended. Zappettini is a
public cul-de-sac serving four residences and has an off-road path exiting from the end: that runs along the
southwestern border of 12660 and 12620 Zappettini. The off-road connection to Central Drive and Byrne
Preserve has not yet been completed, although the Town holds the necessary easements. The Town already
holds a pathway easement along the Zappettini Court frontage of this parcel, but not on the Altamont
frontage. (See attachments.) The existing path along Altamont is narrow and partially blocked by a utility
pole near the western border of the parcel. The fence appears to be located in the road ROW. This path is
close to Byrne Preserve and is heavily used by equestrians, hikers, and cyclists. Auto traffic along Altamont
is heavy and cars often speed along this section. So a path separated from the roadside would be safer. WC
moved that the Town ask the developers of 12501 Zappettini Court to build a standard IIB path along
Altamont Road either in the road right-of-way or in an easement on the parcel. No one seconded. BK
moved that the Town ask that the developers of 12501 Zappettini Court, because of the high traffic volume
on Altamont, to construct a IIB path along Altamont with separation from the road, especially in the area of
the utility poles; said pathway is to be within the road right-of-way to the.extent possible or within an
additional easement as needed. SW seconded and the vote was unanimously in favor.
B. 26495 Altamont Road (Lands of Battenfield: File 1-14-ZP-SD-GD). Review is continued from the January
meeting. The homeowner reported at the January meeting that he is amenable to a roadside path along
Altamont that is located down the slope and separated from the road edge. Because the PWC had not
considered this option, the decision was deferred until after second site visit to explore this option.
Altamont is a "two-sided" public road designated by Council as a road for which roadside paths on both
sides are recommended. The Town already holds a pathway easement along the full Altamont frontage of
this property as well on the adjacent properties to the east (27022 and 27010 Dezahara) and on at least one
additional property further to the east (26385 Altamont Road). (See attachments.) PWC members who
walked these easements report they are amenable to construction of a pathway separated from the road. AD
moved the Town ask the owner of 26495 Altamont Road to build a IIB pathway in the existing easement
below the road along Altamont Road and to remind the owners that the path across their driveway needs to
be etched to be safe for equestrians. EG seconded. The need for a IIB path versus a native path on the
section below the road was discussed. BK amended the motion to specify "construction of a IIB path along
Altamont from the western border extending across the driveway approximately to where Julietta meets
Altamont. Along Altamont to the east and below this point, homeowners are asked to build a native path
within the existing pathway easement. ND seconded and the vote was unanimously in favor.
4. NEW BUSINESS
A. Pathway Blockages. Bill Balson, LAH resident, presented a proposal to install gates on pathways to block
wildlife. (See, attachments.) PWC discussed at length concerns about blocking pathways and limiting
wildlife movement. Issues of expense and feasibility were also raised and it was pointed out that LAH
ordinances do not allow blocking paths. All members spoke in opposition to this proposal and no action
was taken.
Fina1PWC_Min_14-0224 3/28/14
ATTACHMENT 7
TOWN OF LOS ALTOS HILLS
PLANNING DEPARTMENT
26379 Fremont Road - Los Altos Hills, California 94022 • (650) 941-7222 6 FAX (650) 941-3160
WORKSHEET #2
EXISTING AND PROPOSED DEVELOPMENT AREA AND FLOOR AREA
• TURN 1N W[TH YOUR APPLICATION •
PROPERTY OWNER'S NAME j . y C .: 0 Oy e s t r-. •�� > ; ra �•
PROPERTY ADDRESS z C: H y y
'ALCULATED BY Le .% L J 'w z - N Dc t: I DATE S"- 25; 1'l
1..
DEVELOPMENT AREA
Exi_ sting
Proposed
DA Credit Total
A.
House and Garage (from part 2.A)
-t q 3
, 5 �i
Lt
B.
Decking
UK -R
C.
Driveway and Parking
R; . 17 '5'
-
t • 3 Z
D.
Patios and Walkways
E.
Tennis Court
—
F.
Pool and Pool Decking
—
G.
Accessory Building (from part 2.13)
_Y4 3
?'i 3
H.
Solar Panels (ground mounted)
I.
Any Other Coverage
t,
tz
Li -I
Total
io,�o
et,
Roof Mounted Solar Bonus
(LAHMC Section 10-1.502)
yes x
No_ SF
Maximum Development Area -MDA (from worksheet #1)
Maximum Development Area w/ Solar Credit
2. FLOOR AREA
A. HOUSE AND GARAGE
a.. First Floor
b. Second Floor
c. Attic
d. Basement
e. Garage
f. Are over 17'
g. Bunter
B, ACCESSORY BUILDINGS
Existing Proposed
a. First Floor
b. Second Floor c.
c. Attic
d. Basement
Total > +�
Maximum Floor Area -MFA (from worksheet #1)
- °-t L Z.
Total
TOWN USE ONLY I CHECKED BY � DATE
<"A