HomeMy WebLinkAboutASRPC20201104 6.1
PLANNING COMMISSION STAFF REPORT 6.1
TO: Chair and Planning Commission November 10, 2020
SUBJECT: Resolution No. 2020-10, approving Minor Subdivision request MS 851-
2020 and Tree Removal request TR20-0039 allowing for the subdivision
of an existing five-acre parcel into four single family residential parcels
located 1475 Lawrence Road (APN# 206-160-016)
DESCRIPTION
This application is a request to subdivide a five-acre parcel, located at 1475 Lawrence
Road, into four single-family residential parcels. The Tree Removal request would allow
for the removal of two Town-protected Oak trees, with 10 and 14 inch diameters, and six
California Sycamore trees with diameters of 22 to 24.5 inches. There is an existing 5,300
square foot residence which would be retained on proposed Parcel B.
EVALUATION/ DISCUSSION
Conformance with General Plan and Zoning District
The site has a General Plan Land Use Designation of Residential – Country Estates, which
requires a minimum lot size of one acre. The parcel is zoned P-1; Planned Unit
Development District consistent with the requirements of the Lawrence/Leema Road
Specific Plan, with R-40; Single Family Residential District (minimum 40,000 square foot
parcel size minimum) zoning standards. The proposed minor subdivision complies with
all of the minimum requirements of the zoning district, including net lots sizes and
dimensions.
Tree Removal
An arborist report was prepared for this project by Traverso Tree Service (Attachment
C). Approximately 33 trees on the site qualify as Town-protected trees under the Town’s
Tree Protection Ordinance. The 10 inch and 14 inch diameter Valley Oak trees (#25 & 26)
proposed for removal are located within the entrance of the development and are within
the proposed roadway improvements and bio-retention facility near proposed Parcel 1.
The six California Sycamore trees (#5, 6, 7, 8, 9 & 16) are all located within the proposed
private street infrastructure and are recommended for removal. Three California
Sycamore tree (#11, 13 & 15) and the Coast Live Oak (#14) which are proposed to be
removed on proposed Parcel 3 are not recommended for approval at this time. As
recommended, any additional tree removals would be considered in conjunction with
individual Development Plan applications for the development of each parcel. Many of
the existing non Town-protected trees on the site are proposed to be removed. Six Town-
1475 Lawrence Road 2 November 10, 2020
protected Oak trees and one California Sycamore tree located on proposed Parcel 2 would
be preserved.
C.3. Stormwater Control
In compliance with the Town’s Stormwater Management and Discharge Control
Ordinance, future development would be subject to compliance with the Town’s C.3
stormwater pollution control requirements as found in the Stormwater Control Plan .
Individual stormwater treatment facilities are proposed for each of the four proposed
parcels. The storm drain system would be required to be maintained by the homeowners
through a maintenance agreement. The storm drain facilities would be inspected by the
Town on an annual basis.
Parcel Development
As recommended through conditions of approval, the future development of single-
family residences on the proposed Parcels 1, 3 & 4 would be subject to review by the
Design Review Board under separate Development Plan applications. Each residence,
including the existing residence, would be required to connect to public water and sewer
services.
ENVIRONMENTAL REVIEW
The project has been found to be Categorically Exempt from the requirements of the
California Environmental Quality Act (CEQA) Section 15315, Class 15 (Minor Land
Division).
PUBLIC CONTACT
Public notice of the November 10, 2020 hearing was mailed to property owners within
750 feet and posted online. A total of 27 notices were mailed to surrounding property
owners.
RECOMMENDATION
Approve Minor Subdivision request MS 851-2020 and Tree Removal request TR20-0039
allowing for the subdivision of a five-acre parcel into four single family residential
parcels, subject to the findings and conditions of approval contained within Resolution
No. 2020-10.
Prepared by:
David Crompton
Chief of Planning
1475 Lawrence Road 3 November 10, 2020
Attachments: A - Resolution No. 2020-10
B - Public Notification, Notification Map & Notification List
C - Arborist Report (Traverso Tree Service)
D - Tentative Map 851-2020
RESOLUTION NO. 2020-10
APPROVING MINOR SUBDIVISION REQUEST MS 851-2020 AND
TREE REMOVAL REQUEST TR20-0039 ALLOWING FOR THE
SUBDIVISION OF AN EXISTING FIVE-ACRE PARCEL INTO FOUR
SINGLE FAMILY RESIDENTIAL PARCELS LOCATED AT
1475 LAWRENCE ROAD (APN: 206-160-016)
WHEREAS, HAVEN DEVELOPMENT has requested approval of Minor Subdivision
application MS 851-2020 to subdivide an existing five-acre parcel into four single family
residential parcels; and
WHEREAS, the subject site is located at 1475 Lawrence Road and further identified as
Assessor’s Parcel Number 206-160-016; and
WHEREAS, the Town of Danville Subdivision Ordinance requires Planning Commission
approval of a tentative parcel map prior to recordation of a final map; and
WHEREAS, the project is Categorically Exempt from the requirements of the California
Environmental Quality Act (CEQA), Section 15315, Class 15, Minor Land Divisions; and
WHEREAS, the Planning Commission did review the project at a noticed public hearing on
November 10, 2020; and
WHEREAS, the public notice of this action was given in all respects as required by law;
and
WHEREAS, the Planning Commission did hear and consider all reports, recommendations,
and testimony submitted in writing and presented at the hearing; now, therefore, be it
RESOLVED that the Planning Commission approves Minor Subdivision request MS 851-
2020 subject to the conditions contained herein, and make the following findings in support
of this action.
Minor Subdivision:
1.The proposed subdivision is in substantial conformance with the goals and policies
of the 2030 General Plan.
2.The design of the proposed subdivision is in substantial conformance with the
applicable zoning regulations.
ATTACHMENT A
PAGE 2 OF RESOLUTION NO. 2020-10
3.The design of the subdivision and the type of associated improvements will not
likely cause serious public health problems because water and sanitary facility
services will be available to the new parcels.
4.The design of the proposed subdivision and improvements are not likely to cause
substantial environmental damage or subsequently injure fish or wildlife or their
habitat since this property is in an area where residential development has
previously occurred.
5.The design of the proposed subdivision and proposed improvements will not
conflict with easements, acquired by the public at large, for access through or use of,
property within the proposed subdivision.
CONDITIONS OF APPROVAL
Conditions of approval with an asterisk ("*") in the left-hand column are standard project
conditions of approval. Unless otherwise specified, the following conditions shall be
complied with prior to the approval of the final map for the project. Each item is subject to
review and approval by the Planning Division unless otherwise specified.
A. GENERAL
1.This approval is for a Minor Subdivision application MS 851-2020 to
subdivide an existing five-acre parcel into four single family residential
parcels. Development shall be substantially as shown on the project
drawings as follows, except as may be modified by conditions contained
herein;
a.Tentative Parcel Map MS 851-2020 titled “1475 Lawrence Road,” as
prepared by CBG Civil Engineers, consisting of five sheets, dated
October 6, 2020.
b.Tree Survey Report prepared by Traverso Tree Service dated August 22,
2020.
c.Stormwater Control Plan prepared by CBG Civil Engineers, dated
October 6, 2020.
2.All Town and other related fees that the property may be subject to shall be
paid by the applicant. These fees shall be based on the current fee schedule in
effect at the time the relevant permits are secured and shall be paid prior to
issuance of said permit and prior to any Town Council final approval action.
PAGE 3 OF RESOLUTION NO. 2020-10
The following fees are due at final map approval for the above -mentioned
project:
1.Map Check Fee $ 3,406.00
2.Improvement Plan Check Fee 3% of cost estimate
3.Engineering Inspection Fee 5% of cost estimate
4.Grading Inspection, Plan Check & Permit Fee TBD
5.Park Land in Lieu Fee (3 lots)$ 35,012.00
6.Base Map Revision Fee $ 388.00
7.Stormwater Control Plan Review 33% of Consultant Fee
The following fees are due at building permit issuance for the above-
mentioned project:
1.Child Care Facilities Fee $ 335/lot
2.Finish Grading Inspection Fee $ 86/lot
3.Stormwater Pollution Fee $ 56/lot
4.SCC Regional Fee $ 1,544/lot
5.SCC Sub-Reginal Fee $ 4,259/lot
6.Residential TIP Fee $ 2,000/lot
7.Tri-Valley Transportation Fee $ 4,902/lot
3.Prior to issuance of building permit the applicant shall reimburse the Town
for notifying surrounding residents. The fee shall be $304.82 ($130 plus 27
notices x $0.83 per notice x two notices).
* 4. Prior to the issuance of grading or building permits, the applicant shall
submit written documentation that all requirements of the San Ramon Valley
Fire Protection District (SRVFPD) and the San Ramon Valley Unified School
District (SRVUSD) have been, or will be, met to the satisfaction of these
respective agencies.
* 5. In the event that subsurface archeological remains are discovered during any
construction or pre-construction activities on the site, all land alteration work
within 100 feet of the find shall be halted, the Town Planning Division
notified, and a professional archeologist, certified by the Society of California
Archeology and/or the Society of Professional Archeology, shall be notified.
Site work in this area shall not occur until the archeologist has had an
opportunity to evaluate the significance of the find and to outline
appropriate mitigation measures, if they are deemed necessary. If prehistoric
archaeological deposits are discovered during development of the site, local
PAGE 4 OF RESOLUTION NO. 2020-10
Native American organizations shall be consulted and involved in making
resource management decisions.
* 6. Construction activity shall be restricted to the period between the weekday
hours of 7:30 a.m. to 5:30 p.m. (Monday through Friday), unless otherwise
approved in writing by the City Engineer for general construction activity
and the Chief Building Official for building construction activity. Prior to
any construction work on the site, including grading, the property owner
shall install a minimum 3’ x 3’ sign at the project entry which specifies the
allowable construction work days and hours, and lists the name and contact
person for the overall project manager and all contractors and sub-
contractors working on the job.
* 7. The applicant shall provide security fencing, to the satisfaction of the City
Engineer and/or the Chief Building Official, around the site during
construction of the project.
* 8. The applicant shall require their contractors and subcontractors to fit all
internal combustion engines with mufflers which are in good condition, and
to locate stationary noise-generating equipment as far away from existing
residences as feasible.
* 9. A watering program which incorporates the use of a dust suppressant, and
which complies with Regulation 2 of the Bay Area Air Quality Management
District shall be established and implemented for all on and off-site
construction activities. Equipment and human resources for watering all
exposed or disturbed soil surfaces shall be supplied on weekends and
holidays as well as workdays. Dust-producing activities shall be
discontinued during high wind periods.
* 10. As part of the initial submittal for the final map, plan check review process,
the applicant shall submit a written Compliance Report detailing how the
conditions of approval for this project has been complied with. This report
shall list each condition of approval followed by a description of what the
property owner has provided as evidence of compliance with that condition.
The report must be signed by the applicant. The report is subject to review
and approval by the City Engineer and/or Chief of Planning and/or Chief
Building Official, and may be rejected by the Town if it is not comprehensive
with respect to the applicable conditions of approval.
PAGE 5 OF RESOLUTION NO. 2020-10
* 11. Planning Division sign-off is required prior to final Building Inspection sign-
off.
12.For all new parcels created by this subdivision, the following statement shall
be recorded to run with the deed of the property acknowledging the historic
rural nature of the area, and the rights of surrounding property owners to
continue existing and/or future legally established rural and agricultural
uses:
IMPORTANT: BUYER NOTIFICATION
This property is located in a historically rural area with existing rural and
agricultural uses. Any inconvenience or discomfort from properly conducted
agricultural operations, including noise, odors, dust, and chemicals, will not
be deemed a nuisance.
B. SITE PLANNING
* 1. All lighting shall be installed in such a manner that lighting is generally
down-directed and glare is directed away from surrounding properties and
rights-of-way.
2.Any on-site wells and septic systems shall be destroyed in accordance with
Contra Costa County Health Services Department - Environmental Health
Division regulations. Environmental Health Division permits and inspections
for this work shall be obtained. The maintenance of existing on-site wells
shall be allowed for landscape irrigation purposes subject to review and
approval by the Contra Costa County Health Services Department –
Environmental Health Division.
3.The development and use of the parcels created by this subdivision shall
comply with all requirements of the Town’s R-40; Single Family
Residential District Ordinance.
C. LANDSCAPING
1.Preliminary landscape plans shall be submitted for review and approval by
the Design Review Board as part of the individual Development Plan
application for the development of each lot created by this subdivision.
2.This approval allows for the removal of two protected Valley Oak trees (#25
& 26) and the removal of six California Sycamore trees (#5, 6, 7, 8, 9 & 16)
PAGE 6 OF RESOLUTION NO. 2020-10
D. ARCHITECTURE
* 1. All ducts, meters, air conditioning and/or any other mechanical
equipment whether on the structure or on the ground shall be effectively
screened from view with landscaping or materials architecturally
compatible with the main structures.
* 2. The street numbers for each structure in the project shall be posted to be
easily seen from the street at all times, day and night.
3.The development of all four parcels created by this subdivision, including
associated landscaping, shall be subject to the review and approval by the
Town and Design Review Board under a separate Development Plan
application(s).
E. GRADING
* 1. Development shall be completed in compliance with a detailed soils report
and the construction grading plans prepared for this project. The engineering
recommendations outlined in the project specific soils report shall be
incorporated into the design of this project. The report shall include specific
recommendations for foundation design of the proposed buildings and shall
be subject to review and approval by the Town’s Engineering and Planning
Divisions.
* 2. Where soils or geologic conditions encountered in grading operations are
different from that anticipated in the soil report, a revised soils report shall
be submitted for review and approval by the City Engineer. It shall be
accompanied by an engineering and geological opinion as to the safety of the
site from settlement and seismic activity.
* 3. All development shall take place in compliance with the Town Erosion
Control Ordinance (Ord19-4). Restrictions include limiting construction
primarily to the dry months of the year (May through October) and, if
construction does occur during the rainy season, the developer shall submit
an Erosion Control Plan to the City Engineer for review and approval. This
plan shall incorporate erosion control devices such as, the use of sediment
traps, silt fencing, pad berming and other techniques to minimize erosion.
* 4. All new development shall be consistent with modern design for resistance
to seismic forces. All new development shall be in accordance with the
Uniform Building Code and Town of Danville Ordinances.
PAGE 7 OF RESOLUTION NO. 2020-10
* 5. Stockpiles of debris, soil, sand or other materials that can be blown by the
wind shall be covered.
* 6. If toxic or contaminated soil is encountered during construction, all
construction activity in that area shall cease until the appropriate action is
determined and implemented. The concentrations, extent of the
contamination and mitigation shall be determined by the Contra Costa
County Health Department. Suitable disposal and/or treatment of any
contaminated soil shall meet all federal state and local regulations. If
deemed appropriate by the Health Department, the property owner shall
make provisions for immediate containment of the materials.
* 7. Runoff from any contaminated soil shall not be allowed to enter any
drainage facility, inlet or creek.
* 8. All grading activity shall address National Pollutant Discharge Elimination
system (NPDES) concerns. Specific measures to control sediment runoff,
construction pollution and other potential construction contamination shall
be addressed through the Erosion control Plan (ECP) and Storm Water
Pollution Prevention Plan (SWPPP). The SWPPP shall supplement the
Erosion Control Plan and project improvement plans. These documents shall
also be kept on-site while the project is under construction. A NPDES
construction permit may be required, as determined by the City Engineer.
9.The applicant shall create a construction staging plan that addresses the
ingress and egress location for all construction vehicles, parking and material
storage area. All staging of construction materials and equipment shall occur
on-site. This plan shall be subject to review and approval by the Town prior
to the issuance of a grading permit.
F. STREETS
* 1. The applicant shall obtain an encroachment permit from the Engineering
Division prior to commencing any construction activities within any public
right-of-way or easement.
* 2. All mud or dirt carried off the construction site onto adjacent streets shall be
swept each day. Water flushing of site debris or sediment or concrete washing
is expressly prohibited.
* 3. All improvements within the public right-of-way, including driveways,
paving and utilities, shall be constructed in accordance with approved
standards and/or plans and shall comply with the standard plans and
PAGE 8 OF RESOLUTION NO. 2020-10
specifications of the Development Services Department and Chapters XII and
XXXI of the Town Code. At the time project imp rovement plans are
submitted, the applicant shall supply to the City Engineer an up-to-date title
report for the subject property.
4.A satisfactory private road and private storm drain maintenance agreement
shall be submitted for review and approval by the Town prior to recordation
of the final map.
5.The abutters rights shall be relinquished along Lawrence Road that abuts to
Parcel 1.
G. INFRASTRUCTURE
* 1. The new and existing residences shall be required to connect to public water
and sewer facilities, subject to all permitting requirements and conditions
imposed by EBMUD and CCCSD.
* 2. Drainage facilities and easements shall be provided to the satisfaction of the
City Engineer and/or the Chief Engineer of the Contra Costa County Flood
Control & Water Conservation District (CCCFC & WCD).
* 3. All runoff from impervious surfaces shall be intercepted at the project
boundary and shall be collected and conducted via an approved drainage
method through the project to an approved storm drainage facility, as
determined by the City Engineer. Development which proposes to contribute
additional water to existing drainage systems shall be required to complete a
hydraulic study and make improvements to the system as required to handle
the expected ultimate peak water flow and to stabilize erosive banks that
could be impacted by additional storm water flow.
* 4. Roof drainage from structures shall be collected via a closed pipe and
conveyed to an approved storm drainage facility in the street curb. No
concentrated drainage shall be permitted to surface flow across sidewalks.
* 5. If a storm drain must cross a lot, or be in a n easement between lots, the
easement shall be equal to or at least double the depth of the storm drain.
* 6. The applicant shall furnish proof to the City Engineer of the acquisition of all
necessary rights of entry, permits and/or easements for the construction of
off-site temporary or permanent road and drainage improvements.
PAGE 9 OF RESOLUTION NO. 2020-10
* 7. Electrical, gas, telephone, and cable TV services, shall be provided
underground in accordance with the Town policies and existing ordinances.
All utilities shall be located and provided within public utility easements,
sited to meet utility company standards, or in public streets.
* 8. All new utilities required to serve the development shall be installed
underground.
* 9. All street, drainage or grading improvement plans shall be prepared by a
licensed civil engineer.
H. MISCELLANEOUS
* 1. The project shall be constructed as approved. Minor modifications in the
design, but not the use, may be approved by staff. Any other change will
require Planning Commission approval through the subdivision review
process.
* 2. Pursuant to Government Code section 66474.9, the applicant (including the
applicant or any agent thereof) shall defend, indemnify, and hold harmless
the Town of Danville and its agents, officers, and employees from any claim,
action, or proceeding against the Town or its agents, officers, or employees to
attack, set aside, void, or annul, the Town's approval concerning this Minor
Subdivision application, which action is brought within the time period
provided for in Section 66499.37. The Town will promptly notify the
applicant of any such claim, action, or proceeding and cooperate fully in the
defense.
* 3. Use of a private gated entrance for more than one parcel is expressly
prohibited.
* 4. The proposed project shall conform to the Town’s Stormwater Management
and Discharge Control Ordinance (Ord. No. 2004-06) and all applicable
construction Best Management Practices (BMPs) for the site. For example,
construction BMPs may include, but are not limited to: the storage and
handling of construction materials, street cleaning, proper disposal of wastes
and debris, painting, concrete operations, dewatering operations, pavement
operations, vehicle/equipment cleaning, maintenance and fueling and
stabilization of construction entrances. Training of contractors on BMPs for
construction activities is a requirement of this permit. At the discretion of the
City Engineer, a Storm Water Pollution Prevention Plan (SWPPP) may be
required for projects under five acres.
PAGE 10 OF RESOLUTION NO. 2020-10
* 5. The project shall conform to the Regional Water Quality Control Board post-
construction C.3 regulations which shall be designed and engineered to
integrate into the project’s overall site, architectural, landscaping and
improvement plans. These requirements are contained in the project’s
Stormwater Control Plan and are to be implemented as follows:
▪Prior to issuance of permits for building, site improvements, or
landscaping, the permit application shall be consistent with the
applicant’s approved Stormwater Control Plan and shall include
drawings and specifications necessary to implement all measures in the
approved plan. The permit application shall include a completed
Stormwater Control Plan for a Small Land Development Project as
published by the Contra Costa Clean Water Program.
APPROVED by the Danville Planning Commission at a special meeting on November 10,
2020, by the following vote:
AYES:
NOES:
ABSTAINED:
ABSENT:
_____________________________
CHAIR
APPROVED AS TO FORM:
_______________________________ ______________________________
CITY ATTORNEY CHIEF OF PLANNING
ATTACHMENT B
4080 Cabrilho Drive · Martinez, CA 94553 · Telephone (925) 930-7901 · Fax (925) 723-2442
August 6, 2020 (revised 9/22/20)
Premdip Dhoot
925-963-2114 | Pdhoot@haven-development.com
Re: Arborist Report for 1475 Lawrence Road, Danville
Dear Prem,
This arborist report addresses the proposed subdivision improvements at 1475 Lawrence Road.
Per the Town of Danville’s Tree Preservation Ordinance Chapter 32-79, the scope of work
includes:
•Tag, identify and measure all protected trees on or overhanging the property, within 50’
of proposed improvements.
•Note protected trees, defined as:
o Any of the following native trees with a trunk 10” or greater in diameter measured
at 4.5’ above grade, or for a multi-trunked tree, a combination of trunks totally 20”
or greater in diameter: Canyon Live Oak (Quercus chrysolepis), Blue Oak (Q.
douglasii), California Black Oak (Q. kelloggi), Interior Live Oak (Q. wislizenii),
White Alder (Alnus rhombifolia), California Bay (Umbellularia californica), Coast
Live Oak (Q. agrifolia), Valley Oak (Q. lobata), California Buckeye (Aesculus
californica), California Sycamore (Platanus racemosa), Madrone (Arbutus
menziesii), London Plane Tree (Platanus acerifolia)
o Any Heritage (> 36” diameter) or Memorial tree.
o A tree shown to be preserved on an approved Development Plan or specially
required by the Planning Commission to be retained as a condition of approval.
o A tree required to be planted as mitigation for the removal of a protected tree.
•Identify dripline locations and tree numbers on site plan.
•Assess individual tree health and structural condition.
•Assess proposed improvements for potential encroachment.
•Based on proposed encroachment, tree health, structure, and species susceptibility,
make recommendations for preservation.
•Provide appraised values for all trees whose driplines will be encroached.
9/22/20 revision: A minor change was made on page 7, per Planning comments (adding tree
#24 to list of trees to be saved).
Project Summary
The subject property consists of 5 acres in a relatively rural area of Danville, just south of
several subdivisions. The site currently has an existing home, barn, and large open areas that
may have been used for livestock in the past. A large drainage swale runs immediately west of
the house, parallel to Lawrence Road, and continues off-site to the north and south. The house
is primarily accessed via a gated driveway at the south property line, but a secondary driveway
is available along the north property line.
ATTACHMENT C
Revised Arborist Report, 1475 Lawrence Road August 6, 2020 (revised 9/22/20)
Jennifer Tso, Certified Arborist 2
I found thirty-two (32) protected trees on the property. 60% of the trees consist of our native
sycamore (Platanus racemosa; 19 trees), with the remainder consisting of native oaks (eleven
valley oaks, two coast live oaks). Three massive valley oaks in the existing drainage swale are
considered “Heritage” trees on account of their size. Although the species diversity appears low,
my inventory did not include non-protected trees, which comprise a far greater quantity and
variety of trees.
The proposed project consists of a 4-lot subdivision, with the existing home remaining in place
on the second parcel. Site-wide improvements include an enlarged driveway to the north, bio-
retention basins along the driveway, and storm drains between parcels. Building pads and
footprints have yet to be determined, but will likely not affect protected trees except on Parcel 3.
Several trees are found in the center of the lot, where they will likely conflict with the future
home.
It is my opinion that a total of fourteen (14) trees will
need to be removed to accommodate the proposed
project. Two additional oaks next to the proposed
driveway may need to be removed if root loss is high
(Figure 1). The remaining sixteen (16) trees can be
retained given that the protection measures within this
report are followed.
Assumptions & Limitations
This report is based on my site visit on 7/21/20, and the
preliminary site plan (7/22/20) and tree locations plan
(7/28/20) by CBG. It was assumed that the trees and the
proposed improvements were accurately surveyed. Tree
tags #4 & 28 appear to be assigned to the wrong trees,
so I noted the correct locations in my tree protection
plan.
This report only addresses the proposed subdivision
improvements and the potential building pad for Parcel 3
–revisions to the report may be necessary in future
phases of development and/or as designs change. In
particular, the proposed storm drains next to the
heritage oaks (#22-24) currently present a significant encroachment, but my understanding is
that there may be flexibility in future plans to provide additional clearance.
The health and structure of the trees were assessed visually from ground level. No drilling, root
excavation, or aerial inspections were performed. Internal or non-detectable defects may exist
and could lead to part or whole tree failures. Due to the dynamic nature of trees and their
environment, it is not possible for arborists to guarantee that trees will not fail in the future.
Figure 1. Two valley oaks (#1 shown above) may
be subjected to high encroachment from the
proposed driveway, which is located slightly closer
to their trunks than the existing driveway.
Revised Arborist Report, 1475 Lawrence Road August 6, 2020 (revised 9/22/20)
Jennifer Tso, Certified Arborist 3
Tree Inventory & Assessment Table
#s: Each tree was given a square metal tag with numbers ranging from #1-33 (tag #7 was omitted as it was accidentally tagged).
Their locations are given in the tree protection plan.
DBH (Diameter at Breast Height): Trunk diameters in inches were measured at 4.5’ above average grade with a diameter tape.
Height of measurement may deviate from the standard on atypical trunks; deviations are noted under the “Comments” section.
Health & Structural Condition Rating
Dead: Dead or declining past chance of recovery.
Poor (P): Stunted or declining canopy, poor foliar color, possible disease or insect issues. Severe structural defects that may or may
not be correctable. Usually not a reliable specimen for preservation.
Fair (F): Fair to moderate vigor. Minor structural defects that can be corrected. More susceptible to construction impacts than a tr ee
in good condition.
Good (G): Good vigor and color, with no obvious problems or defects. Generally more resilient to impacts.
Very Good (VG): Exceptional specimen with excellent vigor and structure. Unusually nice.
Dripline: Canopy radius was visually estimated in each cardinal direction.
Age
Young (Y): Within the first 20% of expected life span. High resiliency to encroachment.
Mature (M): Between 20% - 80% of expected life span. Moderate resiliency to encroachment.
Overmature (OM): In >80% of expected life span. Low resiliency to encroachment.
DE: Dripline Encroachment (X indicates encroachment)
CI: Anticipated Construction Impact (L = Low, M = Moderate, H = High)
# Species DBH Health Structure Dripline
N E S W
Age DE CI Comments Action
1 Valley oak
(Quercus
lobata)
18 G F 15 0 15 25 Y X M-
H
Upper canopy asymmetrical to west. Minor
clearance pruning from power lines down
driveway. Proposed curb/driveway 4’ to S.
Wrap lower 6’ of trunk
with straw wattle.
Arborist on site during
excavation for driveway.
Trees may need to be
removed if
encroachment is high.
2 Valley oak 20.5 G F 20 20 20 8 M X H co-dominant stems at 10' above grade. Minor
pruning for power line clearance. Proposed
curb/driveway 1’ to S.
3 Valley oak 11.5 G G 15 4 15 8 Y X H Most canopy in upper half due to shading by
shrubs below. In proposed driveway.
Remove.
Revised Arborist Report, 1475 Lawrence Road August 6, 2020 (revised 9/22/20)
Jennifer Tso, Certified Arborist 4
# Species DBH Health Structure Dripline
N E S W
Age DE CI Comments Action
4 California
sycamore
(Platanus
racemosa)
19.5 VG G 18 15 15 10 M X H Nice specimen, compacted gravel 2' to N and
utilities at base of trunk. Within 1’ of
proposed bio-retention basin and driveway.
Remove.
5 California
sycamore
22 VG G 18 18 18 18 M X H Gravel driveway curves around tree. In
proposed bio-retention basin.
Remove.
6 California
sycamore
15.5 G-F G-F 15 15 15 15 M X H co-dominant stems at 7' with wide
attachment. Slightly sparse canopy from
anthracnose. Gravel driveway approximately
8' from base of tree. Trunk engulfing old
stake tie. In proposed driveway.
Remove.
8 California
sycamore
14 G G-F 15 15 15 15 Y X H Upper trunks not straight, minor anthracnose.
In proposed driveway.
Remove.
9 California
sycamore
24.5 VG G 20 20 20 20 M X H Nice tree, minor anthracnose. Strong
structure. Large surface roots - 5" root at 10'
north of trunk. 2’ from proposed bio-retention
basin.
Remove.
(Can be retained if bio-
retention is moved to 10’
from trunk)
10 California
sycamore
23.5 G G-F 20 20 20 20 M X M Large visible surface roots (3.5" root 10'-12'
N) and large buttress root mass to W. 2 roots
girdling approx. half of circumference. 14’
from proposed bio-retention basin; 22’ from
proposed storm drain.
Install temporary
protection fencing.
Cleanly prune roots > 2”
diameter.
11 California
sycamore
23 G-F F 15 15 18 15 M X H Co-dominant stems at 7' above grade with
relatively narrow attachment. Massive
surface roots within 8'-10' of trunk (3" at 10').
Minor cracking of concrete curb. Canopy
slightly sparse at top due to anthracnose. In
likely building footprint.
Remove.
12 California
sycamore
21 VG G 15 15 20 15 M X M One branch elongated to S. Suckers. 11’
from proposed storm drain.
Install temporary
protection fencing.
Cleanly prune roots > 2”
diameter.
Revised Arborist Report, 1475 Lawrence Road August 6, 2020 (revised 9/22/20)
Jennifer Tso, Certified Arborist 5
# Species DBH Health Structure Dripline
N E S W
Age DE CI Comments Action
13 California
sycamore
17 G G-F 15 15 15 15 M X H Multiple stems at 25' above grade. 2.5"
surface root 10' to S. Curb around NE side of
trunk with minor cracking. Gravel around N
side of dripline and to S outside curb. In likely
building footprint.
Remove.
14 Coast live
oak (Quercus
agrifolia)
17,
23
G P 25 25 25 20 M X H Two co-dominant trunks previously failed
(included bark); remaining 2 trunks
compromised. Canopy predominantly to N &
W except for one secondary branch. Minor
sycamore borer. In likely building footprint.
Remove.
15 California
sycamore
14 F F 15 15 15 15 M X H Slightly understory tree - dominated by oak
and wisteria. In likely building footprint.
Remove.
16 California
sycamore
17.5 VG G 10 15 10 15 M X H Asymmetrical canopy due to crowding. Large
secondary stem at 5.5' becoming vertical. 2'
from concrete (may be causing lift). 1’ from
proposed storm drain.
Remove.
17 California
sycamore
22.5 G G-F 15 15 15 15 M L Large secondary branch at 5' becoming
vertical; co-dominant stems at 15' with
narrow attachment. Brick wall/patio 3' to W.
Upper canopy slightly sparse (anthracnose).
Clear of construction.
None.
18 Valley oak 12 G F 35N-20NW Y L 20° phototrophic lean to N. Co-dominant
stems at 15'. Trunk flare appears slightly
buried. Clear of construction.
None.
19 Valley oak 14.5 G F 0 20 0 0 Y L 25° phototrophic lean to E. Trunk flare
appears slightly buried. In crowded grove,
canopy leaning over driveway. Clear of
construction.
None.
20 California
sycamore
10.5,
12
F F 6 10 10 0 M L Asymmetrical due to shading. Parallel co-
dominant stems at 2.5' above grade. Sparse
canopy. Proposed storm drain to be installed
south of driveway.
None.
Revised Arborist Report, 1475 Lawrence Road August 6, 2020 (revised 9/22/20)
Jennifer Tso, Certified Arborist 6
# Species DBH Health Structure Dripline
N E S W
Age DE CI Comments Action
21 Valley oak 32.5 G G-F 35 35 35 35 M L Located on face of creek bank. Sprouting
along scaffold branches. Proposed storm
drain 45’ to W & 29’ to S. Proposed storm
drain to be installed south of driveway.
None.
22 Valley oak 52 F F 15 40 35 35 M X H Heritage tree. Closed cankers on lower
trunk; 2.5' scar at 10' with cement paint.
Moderate small dieback with bare interior
scaffolds (not much sprouting). Some large
diameter deadwood and decay of old pruning
cuts. Elongated scaffolds. 20’ from proposed
storm drain.
Move storm drain at
least 40’ from trunk; any
encroachment closer
than 40’ will need to be
review by arborist and
will be subject to more
tree protection. Install
temporary 6’ protection
fencing. Consult arborist
if roots > 2” diameter are
encountered during
excavation.
23 Valley oak 47 G-F G-F 25 30 30 30 M X M-
H
Heritage tree. Droopy foliage (unknown
cause), good interior sprouting. Multiple large
stems at 15' above grade. Sprinkler 5' W of
trunk. 18" scaffold removed to N with minimal
wound closure. Structural root damaged to E
(electrical nearby). Canopy opened to N due
to scaffold branch removal. 32’ from
proposed storm drain.
24 Valley oak 46 G-F F 20 20 25 35 M X H Heritage tree. Phototrophic lean to W.
Torsioned appearance to trunk. 25’ from
proposed storm drain.
25 Valley oak 10 G F-P 20SW Y X H Understory tree. Phototropic lean to SW
(right next to English oak). In proposed
driveway.
Remove.
26 Valley oak 14 G G-F 10 10 10 15 Y X H Partially clearance pruned for power lines.
Trunk flare slightly buried; small oak at base.
In proposed driveway.
Remove.
27 Coast live
oak
16,
12.5,
21
(31 at
base)
G-F F 15 15 20 20 M L-
M
Curb approximately 6' from trunk. Trunk
staining with multiple stems at 3'; wide
attachment but appears to be
separating/included bark/decayed. 17’ & 23’
from proposed storm drain.
Install temporary
protection fencing.
Cleanly prune roots > 2”
diameter.
Revised Arborist Report, 1475 Lawrence Road August 6, 2020 (revised 9/22/20)
Jennifer Tso, Certified Arborist 7
# Species DBH Health Structure Dripline
N E S W
Age DE CI Comments Action
28 California
sycamore
13,
12.5
G F 15 12 12 5 M X H Parallel vertical co-dominant stems at 2.5'.
Curb cracked to N, 2' from base of trunk and
extending half the width of driveway.
Proposed SD 2’ to E.
Remove.
29 California
sycamore
15 G-F G-F 15 5 15 8 M L Very little branching in lower half of tree,
mostly from suckers. 5" sucker growing low
to N. Clear of construction.
Install temporary
protection fencing.
30 California
sycamore
10 G-F F 15 10 10 6 Y L Tall skinny tree. 3' from existing curb. Clear
of construction.
None.
31 California
sycamore
16 G-F G 18 10 18 8 M L Suckers. Clear of construction. None.
32 California
sycamore
14 F F 20 5 15 6 Y L Suckers. Co-dominant vertical stems with ok
attachment at 15'. Dieback from anthracnose,
slightly sparse canopy. Clear of construction.
None.
33 California
sycamore
14.5 G G-F 15 6 15 10 Y L All branching in upper half of tree. Clear of
construction.
None.
Tree Encroachment Summary
• Trees that will need to be removed: 3-6, 8, 9, 11, 13-16, 25, 26, 28 (14 trees)
• Trees to be saved that will be subjected to dripline encroachment: 1, 2, 10, 12, 21-24 (8 trees, revised 9/22/20)
• Trees to be saved whose driplines will not be encroached: 17-21, 27, 29-33 (11 trees)
Revised Arborist Report, 1475 Lawrence Road August 6, 2020 (revised 9/22/20)
Jennifer Tso, Certified Arborist 8
Tree Appraisal
Per city ordinance, appraisals are required for all protected trees whose driplines will be
encroached. The following appraised values were determined using the Trunk Formula Method,
used for larger trees that cannot be readily replaced by equal-sized specimens. All figures
below were calculated using a worksheet formatted from The Guide for Plant Appraisal (10th
Edition) written by the Council of Tree & Landscape Appraisers. Trunk unit cost was adapted
from the Species Classification and Group Assignment Guide from the Western Chapter of the
International Society of Arboriculture.
# Species DBH Basic
Reproduction
Cost
Condition Functional
limitations
External
limitations
Depreciated
Reproduction
Cost
1 Valley oak 18 $ 19,604.34 66% 80% 50% $5,175.55
2 Valley oak 20.5 $ 25,428.16 66% 80% 50% $6,713.03
3 Valley oak 11.5 $ 8,002.08 80% 60% 70% $2,671.89
4 California sycamore 19.5 $ 13,576.55 87% 80% 90% $8,475.03
5 California sycamore 22 $ 17,280.87 87% 80% 90% $10,787.41
6 California sycamore 15.5 $ 8,577.95 75% 70% 90% $4,053.08
8 California sycamore 14 $ 6,998.04 84% 80% 90% $4,207.22
9 California sycamore 24.5 $ 21,431.50 90% 80% 90% $13,887.61
10 California sycamore 23.5 $ 19,717.69 84% 80% 90% $11,925.26
11 California sycamore 23 $ 18,887.57 73% 75% 90% $9,243.10
12 California sycamore 21 $ 15,745.59 88% 80% 90% $10,016.08
13 California sycamore 17 $ 10,318.54 81% 75% 90% $5,606.84
14 Coast live oak 17, 23 $ 29,000.80 39% 75% 80% $6,786.19
15 California sycamore 14 $ 6,998.04 65% 40% 90% $1,631.24
16 California sycamore 17.5 $ 10,934.44 79% 70% 90% $5,442.07
22 Valley oak 52 $ 163,611.51 64% 70% 80% $58,638.37
23 Valley oak 47 $ 133,660.44 80% 75% 80% $64,421.66
24 Valley oak 46 $ 128,033.27 78% 70% 75% $52,664.88
25 Valley oak 10 $ 6,050.72 53% 40% 80% $1,026.20
26 Valley oak 14 $ 11,859.41 79% 75% 70% $4,931.14
28 California sycamore 13, 12.5 $ 11,568.19 70% 70% 80% $4,534.73
Total Estimated Value of Appraised Trees $292,838.60
Revised Arborist Report, 1475 Lawrence Road August 6, 2020 (revised 9/22/20)
Jennifer Tso, Certified Arborist 9
Discussion
Protected trees on the site are largely in good condition, both because they are native trees
adapted to the region and from supplemental irrigation. Reduced health or structure appears to
be a result of overcrowding, since the trees are largely found in densely packed rows or
clusters.
The proposed driveway will require the removal of eight (8) protected trees along the north
property line, which may be increased by two additional off-site oaks if root loss is high (trees #1
& 2, Figure 1). The existing driveway is currently close to the two oaks, but the new driveway is
slightly closer and may sever all the roots growing to the south. The construction impact is
further extended into the property by proposed bio-retention basins along the south edge of the
driveway. I identified one sycamore (#9) that might be retained if the closest basin were
relocated further away; however, the feasibility of saving the tree may be limited by the
placement of the future home.
The new storm drains are located along
the perimeters of parcel 2 & 3. Two trees
(#16 & 28) are located in and within 2’ of
the storm drains, so they will need to be
removed. The proposed storm drain on
Parcel 1, west of the Contra Costa
County drainage easement, is of
particular concern due to the three
massive oaks located in the swale.
These valley oaks (#22-24, Figure 2)
were likely in the original native
landscape, well before the construction
of the existing home. I highly
recommend moving the proposed storm
drain to at least 40’ from their trunks, up
to 20’ west of its current position. Growth
slows with age, so old trees are less
capable of closing wounds and replacing
roots and branches that are removed
during construction. Thus, the tree
protection area is significantly greater
than that required for small young trees.
The three oaks are currently in good
health, so every effort shall be made to
ensure that the proposed construction
does not injure them to the point of
triggering their decline. The
recommendations in this report are
based on the assumption that the storm
drain can be relocated as specified – if
that is not possible, additional
investigation, review, and
recommendations may be necessary.
Figure 2. The three Heritage oaks (trees #23, center and #24 left) in the
existing drainage swale will be subjected to high encroachment per the
current storm drain design. Due to their size and age, the drain location will
need to be relocated in order to save them.
Revised Arborist Report, 1475 Lawrence Road August 6, 2020 (revised 9/22/20)
Jennifer Tso, Certified Arborist 10
Lastly, Parcel 3 is the only lot where protected trees will definitely need to be removed for the
proposed home. Although the building pad/footprint has not be finalized, there are several
protected trees in the center of the property, north of the existing barn. One of the trees is a
coast live oak (tree #14, Figure 3) which lost half of its canopy when two of its trunks failed. The
tree had four co-dominant trunks with included bark, which is the cause of its failure. Trees with
good structure usually have single trunks
with smaller scaffold branches. The size
differential allows the trunk tissue to wrap
around branches as the trunk expands in
diameter, slowly embedding branches into
its girth. Co-dominant stems or trunks are
similar in size and essentially grow as two
separate trees with a common point of
origin, exerting pressure on each other until
the weaker stem(s) fail. The previous failure
has compromised the structure of the oak,
and the remaining two stems are likely to
repeat the failure in the future. I recommend
removing the tree in general, especially if a
house will be located nearby.
Tree Protection Recommendations (to be
printed on site plans)
Design Phase
• Adjust location of proposed storm
drain to provide 40’ clearance from
trees #22-24 to reduce
encroachment. If this is not feasible,
the project arborist shall review the
latest plans to determine
encroachment and to provide
recommendations.
• If desired, tree #9 can be saved if the
proposed bio-retention basin is
shifted to provide 10’ clearance from
its trunk, assuming there is no additional encroachment from the proposed home.
Pre-Construction Phase
• Remove trees #3-6, 8, 9, 11, 13-16, 25, 26 & 28 (14 trees).
• Wrap lower 6’ of the trunks of trees #1 & 2 with straw wattle to prevent accidental
contact damage during construction.
• Mulch from tree removals shall be spread out under the driplines of trees that will be
retained, keeping at least 12” away from the trunks.
• Prior to construction or grading, contractor shall install 6’ chain-link fencing to construct a
temporary Tree Protection Zone (TPZ) around each tree or grove of trees as indicated
on the tree protection plan. Orange poly or wire fencing shall not be used as it is easily
encroached.
• TPZ fencing shall remain in an upright sturdy manner from the start of grading until the
completion of construction. Fencing shall not be adjusted or removed without consulting
the project arborist.
Figure 3. Two stems on tree #14 split and failed. The remaining
stems are also compromised – keeping this tree near the future home
on Parcel 3 would create a hazard.
Revised Arborist Report, 1475 Lawrence Road August 6, 2020 (revised 9/22/20)
Jennifer Tso, Certified Arborist 11
Foundation, Grading, and Construction Phase
• The project arborist shall be on-site during excavation/grading within the driplines of
trees #1 & 2. If root encroachment is high, the trees may need to be removed.
• Assuming 40’ clearance is provided for trees #22-24, consult the project arborist if roots
> 2” diameter are encountered during excavation for the storm drain.
• In general, but especially for trees #10, 12 & 27, roots > 2” shall be cleanly pruned with a
handsaw or sawzall, immediately covered, and kept moist till backfilled.
• If needed, pruning shall be performed by personnel certified by the International Society
of Arboriculture (ISA). All pruning shall adhere to ISA and American National Standards
Institute (ANSI) Standards and Best Management Practices.
• Should Tree Protection Zone (TPZ) encroachment be necessary, the contractor shall
contact the project arborist for consultation and recommendations.
• Contractor shall keep TPZs free of all construction-related materials, debris, fill soil,
equipment, etc. The only acceptable material is mulch spread out beneath the trees.
• Should any damage to the trees occur, the contractor shall promptly notify the project
arborist to appropriately mitigate the damage.
Landscaping Phase (if applicable)
• The Tree Protection Zone (TPZ) fencing shall remain in place with the same restrictions
until landscape contractor notifies and meets with the project arborist.
• Avoid all fill work, grade changes, and trenching within driplines unless it is performed by
hand.
• Pipes shall be threaded under or through large roots without damaging them.
• All planting and irrigation shall be kept a minimum of 10’ away from native oaks. All
irrigation within the driplines shall be targeted at specific plants, such as drip emitters or
bubblers. No overhead irrigation shall occur within the driplines of native oaks.
• All planting within oak driplines shall be compatible with oaks, consisting of plant
material that requires little to no water after two years’ establishment. A list of oak-
compatible plants can be found in a publication from the California Oak Foundation,
available at: http://californiaoaks.org/wp-
content/uploads/2016/04/CompatiblePlantsUnderAroundOaks.pdf
Thank you for the opportunity to provide this report, and please do not hesitate to contact me if
there are any questions or concerns.
Please see attached tree protection plan.
Sincerely,
Jennifer Tso
Certified Arborist #WE-10270A
Tree Risk Assessor Qualified
PARCEL DPARCEL CPARCEL B
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MINOR SUBDIVISION 851-2020
PRELIMINARY LOT LAYOUT
TENTATIVE PARCEL MAP
1475 LAWRENCE ROAD
TOWN OF DANVILLE CONTRA COSTA COUNTY CALIFORNIA
SCALE: 1" = 40'DATE: OCTOBER 6, 2020
P-1 (R-40) DEVELOPMENT
STANDARDS
CLASSIFICATION STANDARD
OF SHEETS
SHEET NO.
TM-1
5
GENERAL NOTES:
VICINITY MAP
LEGEND PARCEL SUMMARY TABLE
PARCEL AREA (GROSS)AREA (NET)
SHEET INDEX
TM-1 PRELIMINARY LOT LAYOUT
TM-2 EXISTING TOPOGRAPHIC MAP
TM-3 PRELIMINARY PARCEL MAP
TM-4 PRELIMINARY GRADING, DRAINAGE, AND UTILITY PLAN
TM-5 PRELIMINARY STORMWATER CONTROL PLAN
ABBREVIATIONS
CIVIL ENGINEERS SURVEYORS PLANNERS
SAN RAMON
WWW.CBANDG.COM
SACRAMENTO
(925) 866-0322
(916) 375-1877
12080400
SITE
ATTACHMENT D
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MINOR SUBDIVISION 851-2020
EXISTING TOPOGRAPHIC MAP
TENTATIVE PARCEL MAP
1475 LAWRENCE ROAD
TOWN OF DANVILLE CONTRA COSTA COUNTY CALIFORNIA
SCALE: 1" = 40'DATE: OCTOBER 6, 2020
OF SHEETS
SHEET NO.
TM-2
5
CIVIL ENGINEERS SURVEYORS PLANNERS
SAN RAMON
WWW.CBANDG.COM
SACRAMENTO
(925) 866-0322
(916) 375-1877
12080400
LEGEND
EXISTING TREES TO
REMAIN
TREE NUMBER TREE SPECIES
EXISTING TREES TO BE
REMOVED
TREE NUMBER TREE SPECIES
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MINOR SUBDIVISION 851-2020
PRELIMINARY PARCEL MAP
TENTATIVE PARCEL MAP
1475 LAWRENCE ROAD
TOWN OF DANVILLE CONTRA COSTA COUNTY CALIFORNIA
SCALE: 1" = 40'DATE: OCTOBER 6, 2020
OF SHEETS
SHEET NO.
TM-3
5
LEGEND
CIVIL ENGINEERS SURVEYORS PLANNERS
SAN RAMON
WWW.CBANDG.COM
SACRAMENTO
(925) 866-0322
(916) 375-1877
12080400
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MINOR SUBDIVISION 851-2020
PRELIMINARY GRADING, DRAINAGE, AND UTILITY PLAN
TENTATIVE PARCEL MAP
1475 LAWRENCE ROAD
TOWN OF DANVILLE CONTRA COSTA COUNTY CALIFORNIA
SCALE: 1" = 40'DATE: OCTOBER 6, 2020
OF SHEETS
SHEET NO.
TM-4
5
CIVIL ENGINEERS SURVEYORS PLANNERS
SAN RAMON
WWW.CBANDG.COM
SACRAMENTO
(925) 866-0322
(916) 375-1877
12080400
26' PRIVATE STREET
(PARCELS A & B)
LEGEND
1
1
30' PRIVATE STREET
(PARCELS C & D)
CULVERT CROSSING
PARCEL DPARCEL C
PARCEL A
DMA 1
1.17 AC
DMA 3
1.16 AC
DMA 4
1.34 AC
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MINOR SUBDIVISION 851-2020
PRELIMINARY STORMWATER CONTROL PLAN
TENTATIVE PARCEL MAP
1475 LAWRENCE ROAD
TOWN OF DANVILLE CONTRA COSTA COUNTY CALIFORNIA
SCALE: 1" = 40'DATE: OCTOBER 6, 2020
OF SHEETS
SHEET NO.
TM-5
5
CIVIL ENGINEERS SURVEYORS PLANNERS
SAN RAMON
WWW.CBANDG.COM
SACRAMENTO
(925) 866-0322
(916) 375-1877
151050
LEGEND
DMA 1
1.00 AC
PRE PROJECT AND POST PROJECT COMPARISON
DRAINAGE MANAGEMENT SUMMARY TABLE
DRAINAGE
MANAGEMENT
AREA
TOTAL AREA (SF)ASPHALT OR
CONCRETE (1)(2)
CONVENTIONAL
ROOF (2)LANDSCAPE
DMA 1 50,858 12,771 10,050
BIORETENTION
TREATMENT AREA
(SF)
2,376
4,895
52,188 14,953 7,329
57,083 13,608 11,932
8,304 --
DMA 2
DMA 4
SELF-TREATING
TOTAL
DMA 3
308
2,118
2,589
-
7,391
33,222
22,278
28,954
8,304
25,661
227,828 46,227 29,311 118,419
59,395 -
BIORETENTION
PONDING DEPTH
(IN)
TOTAL IMPERVIOUS AREA (SF)TOTAL PERVIOUS AREA (SF)
10
10
10
10
-
-
PRE-PROJECT
IMPERVIOUS AREA
TO REMAIN (SF) (3)
-
20,903
5,510
-
-
26,413