HomeMy WebLinkAboutStaff Report 5.C 03/20/20065.0
CITY OF PETALUMA, CALIFORNIA March 20, 2006
AGENDA BILL
Agenda Title: Meeting Date:
Council discussion on Flood Protection Next Steps; provide 20 March 2006
feedback and/or direction to City Management
Meetine Time: ❑ 3:00 PM
® 7:00 PM
Cateeory (check one): ❑ Consent Calendar ❑ Public Hearing ® New Business
❑ Unfinished Business ❑ Presentation
Department: I Director: I Contact Person: Phone Number:
City Manager I Mike Bierman I Mike Bierman 778-4345
Cost of Pronosal: Account Number:
N/A
Amount Budgeted: Name of Fund:
N/A N/A
Attachments to Aeenda Packet Item:
Memorandum
Summary Statement:
The City Council has requested Council discussion on a number of topics relating to Flood Protection.
This issue has been addressed in a piecemeal fashion for several decades, with funding and priority focused
primarily on the Payran Reach Corps of Engineers project, which is nearing completion. Work relating to
the General Plan 2025 and the associated Environmental Impact Report and Master Plans (Water Supply,
Recycled Water, and Surface Water) is wrapping up. All of the issues discussed in the attached
memorandum relate to the continued growth rates and patterns for the community to be guided by the new
General Plan. Discussion of Water Supply and temporary suspension of building activities within the
Floodplain, as interim and long-term issues, are scheduled for the Council meeting of April 3, 2006.
Recommended Citv Council Action/Sueeested Motion:
Discussion of topics regarding flood protection: 1) Detention/Retention Feasibility; 2) Sonoma County
policies on zero net fill; 3) General Plan 2025 Draft Land Use — Agriculture designation; 4) XP-SWMM
Model Runs — High Tide calculations; 5) Industry Lead Railroad Trestle; 6) Stream Maintenance; and, 7)
Floodplain Development Moratorium. Provide feedback and/or direction to City Management.
Reviewed by Admin. Svcs. Dir
Date:
Todav's Date:
10 March 2006
Reviewed by City Attornev:
�0� Date:
/lJ/X1J '�// ylti0
Revision # and Date Revised:
Anar v d by City Manaeer:
Date:
File Code:
s:pUreports\CC flood issues 032006
1
CITY OF PETALUMA, CALIFORNIA
MEMORANDUM
Office of the City Dlaaager
11 English Street, Petaluma, CA 94952
(707) 778-4345 Far (707) 778-4419 E-mail. citymgr@ci.petaluma.ca.us
DATE: 10 March 2006
TO: Mayor and Councilmembers
FROM: Mike Bierman, City Manager o`
SUBJECT: Flood Protection Next Steps
The City Council has requested Council discussion on a number of topics relating to Flood
Protection. This issue has been addressed in a piecemeal fashion for several decades, with
funding and priority focused primarily on the Payran Reach Corps of Engineers project, which is
nearing completion. An extraordinary amount of evaluation and analytical work has been
underway for the last four years on the completion of the Water Master Plans (Water Supply,
Recycled Water and Surface Water Management) in conjunction with the preparation of the
General Plan 2025. The Water Resources Element is the last piece being completed for the
General Plan, partially due to recent events, including the December 31s` flood and the
completion of parcel -specific water demand analysis. General Plan related work also related to
the following water topics:
Detention/Retention Feasibility
The concept of utilizing detention/retention facilities to assist in surface water management
during winter storms has existed since the 1970's. The first Master Drainage Plan for the
Petahuma River, prepared in the early 1980's, called for major surface water capital
improvements, including the East Side Bypass and Denman Dam. The City Zoning Ordinance
has, for several decades, required compliance to zero net fill and minimum floor elevations to
protect property from inundation in a 100 -year storm event. On specific projects the City has
required on-site detention ponds to capture peak flows and minimizing off-site flow increases
from the development.
The concept of a regional network of retention/detention basins is a key component to the long-
term management and accommodation of storm water flows for the Petaluma Watershed.
Discussions have commenced with the Sonoma County Water Agency on the utilization of XP-
SWMM for assessing the viability of various locations. The recalibration of the XP-SWMM
model, now underway, to reflect the data obtained from the December 31, 2005 flood event and
the running of the model utilizing current data will allow the City to determine the area needed to
accommodate anticipated storm flows. The model runs will be analyzed using the both the
Corps of Engineers standard mean high tide elevation and the 100 -year high tide elevation.
Evaluating the results will allow the identification of a river corridor and capital improvements,
in conjunction with a regional approach to surface water management, to be incorporated into the
General Plan Land Use, Natural Environmental and Water Resources Elements.
The U. S. Army Corps of Engineers Detailed Project Report for the Payran Reach Flood Control
Project identified the existing benefit of the storm water retention naturally occurring in the
2
Mayor and Councibnembers 10 March 2006
Re: Flood Protection Next Steos Pave 2
Denman Flat area. In order to preserve the design conveyance capacity of the flood control
project, preservation of this storage capacity is crucial.
Subsequent to the certification of the General Plan EIR and adoption of the General Plan
2025, work will begin on regional watershed analysis and design feasibility to identify
workable locations for a network of detention/retention basins.
Sonoma County — Zero Net Fill
During early community meetings, held by the County Citizen's Advisory Committee, City staff
(Pamela Tuft and Dean Eckerson) provided testimony requesting the County General Plan 2020
include provisions for enforcing a zero -net fill policy within the Petaluma River Watershed. In
addition, letters have been written to the County requesting inclusion of similar policies and
regulations in the Plan and accompanying Development Codes (see attached letters dated August
2003 and September 2003). Emphasis was placed on the areas in proximity to Willowbrook,
Liberty, and Marin Creeks and areas subject to low flow inundation during peak storms.
According to the County Permit and Resource Management Department they have been utilizing
zero -net fill policies on projects requiring a discretionary entitlement process. The Sonoma
County Draft General Plan includes policies to address a cooperative approach with the City of
Petaluma and a regional solution (see attached excerpt). A letter will be prepared recognizing
and thanking the County for their cooperative approach, offering support for the draft
General Plan 2020 text, and indicating interest in researching and developing a regional
solution.
General Plan 2025 Land Use - Agricultural Designation
The three land use alternatives included in the report released in January 2004 and discussed
during fourteen months of workshops through the Planning Commission and City Council
included the recommended amendment of land use designation for three parcels, located at the
northwest edge of the City, from Agriculture to Commercial, Business Park and Urban
Separator. The intent of that recommendation was to allow a proactive approach to
incorporating historic storm flows and retention with limited development potential. The water
depths on these parcels during the flood of December 31, 2005 have caused City staff to
reconsider that recommendation; the Draft General Plan 2025 will not include the
recommendation to amend the Ag designation of these three parcels. Premature amendment
may lead to the assumption of development potential unlikely given the historic flow patterns.
Through discussion within the General Plan text and policies, contained in several Elements,
opportunities will be identified for consideration of a future General Plan amendment in the
event a regional approach to surface water management is designed and implemented, which
allows for development to work in concert with storm retention needs.
XP-SWMM Model Runs — High Tide
The dynamic, computer-based surface water management model (XP-SWMM) created for the
General Plan 2025 work effort was created first to identify existing conditions and calibrate to
actual rainfall and stream gage data. Input data for the initial model run included topography,
creek and river cross sections, vegetation thickness, and occlusion of existing creekbeds and
culverts by sedimentation, debris and plant growth. The model nm was very useful in that it
illustrated impacts associated with blocked culverts in numerous locations, resulting in a
narrowed floodplain downstream of the occluded culverts. This initial model run was an
effective tool for identifying maintenance needs. However, a maintenance standard to allow a
S \TAWEMOSWjLe 9icrtwMNIB to CC hood issues 031006 dot
Mayor and Cmmcilmembers 10 March 2006
Re: Flood Protection Next Steos Page 3
minimum flow capacity is necessary to adequately evaluate storm flow impacts along the entire
river corridor.
Following the December 31, 2005 flood event a decision was made to recalibrate the model
using the data and inundation mapping obtained during the flood. The Corps of Engineers, in
determining high tide elevations, measure the datum at the Golden Gate Bridge; with a local
reference point at the D Street bridge. According to the Army Corps of Engineers Detailed
Project Report for the Petaluma Flood Control Project, "It is concluded that tide action has little
effect on the ability of the proposed project to carry the design discharge." The report found that
after analyzing the full range of tides as measured at the Highway 101 bridge over the Petaluma
River, there is only a 4/10ths of a foot difference in the water surface elevation at the Payran
Street bridge. What is commonly used, industry wide for modeling, is the mean of the highest
two tides, called Mean Higher High Water (MHHW). However, at the request of Council,
upon completion of the recalibration effort, now underway, the model will be rerun using
both the Corps standard MHHW and the 100 -year high tide to ascertain the different
impacts associated with each tide elevation.
Industry Lead Railroad Track — Corps of Engineers
The remaining task in completing the Corps of Engineers Payran Reach flood control project is
the removal of the railroad spur line bridge downstream of the Lakeville Street river crossing. A
new railroad spur line serving Dairymen's Feed and Supply must be constructed from the
mainline railroad to allow removal of the trestle bridge. City staff continues to pursue the
additional Corps funding necessary to complete this work.
Stream Maintenance
Maintenance responsibility for the many miles of creeks and channels within Petaluma is divided
between the Sonoma County Water Agency, the City, and private ownership. Every year the
City identifies and informs the Water Agency of the priorities within the City's jurisdiction. In
addition we operate an on-going maintenance program for the creels and channel sections within
City responsibility.
Immediately after the December 2005 flood, staff met with the Water Agency and the
Department of Fish and Game to identify emergency work to restore proper storm flow function
for the remainder of this storm season. That meeting resulted in the identification of work to be
undertaken immediately by the Water Agency. A portion of the work has commenced,
dependent upon the ability to meet regulatory permitting requirements. The City has indicated to
the Water Agency our willingness to assist in obtaining permits for up to 15 sites in Petaluma.
This work will be undertaken by the Water Agency during the summer of 2006. City costs,
associated with obtaining regulatory permits, will be reimbursed by the Agency.
The XP-SWMM model will assist the City in identifying streambed flow needs. Continued
support of regional and local stream maintenance activities, through Zone 2A funding
allocations, should be emphasized by the Council through the Council liaison to the Zone
2A Committee.
Floodplain Development Moratorium
In response to requests by Councilmembers, under the City Council's Rules, Policies &
Procedures, the City Attorney is drafting an interim ordinance tinder California Government
Code Section 65858 for Council adoption as an urgency item for the City Council meeting of 14
5 \Tuft\ ENJOS\h0kc Oie=an\M13 to CC flood issues 031006 doc
Mayor and Councilmembers /0 March 2006
Re: Flood Protection Nett Stens Pave 4
April 3. The draft interim ordinance, as proposed, would halt the issuance of building permits in
the area of the 100 -year flood plain, as designated by the 1989 Flood Insurance Rate Maps, in
areas "upstream of the constriction weir" while the City continues to analyze the impacts of
flooding in this area by means of the XP-SWMM surface water model and address those
findings, as directed by the Council and community, through the General Plan and General Plan
EIR. As mentioned previously, the model is currently being re -calibrated to incorporate all of the
data from the December 30-31 flood. An exhibit illustrating the areas of inundation during the
December 31, 2005 flood event as an overlay on the 100 -year regulatory Floodplain is attached.
The Council is familiar with the adoption of interim ordinances under Section 65858, but it is
important to remind the Council that an interim ordinance cannot halt the processing of
applications for permits (whether they are building or zoning related); only a decision prohibiting
certain uses that may be in conflict with a contemplated general plan, specific plan or zoning
proposal. In this case, the Council's request is to prohibit building permits in the area upstream
of the constriction weir. The practical effect of that limitation through the interim ordinance is
that some projects that may not have entitlements, even after the interim ordinance was adopted,
would be allowed to continue through the development review process up to the point at which a
building permit application would be ready to issue. On the other hand, existing development in
the 100 -year flood plain upstream of the constriction weir, for example, the industrial buildings
along Industrial Drive or the area along North McDowell, north of Corona Road, would be
prohibited from getting a building permit for any work that they might want to do while the
interim ordinance is in effect. If the Council were to make the interpretation that all existing
development in the area subject to the interim ordinance was already entitled and, therefore,
exempt from the ordinance as proposed by Councilmembers, then the Council would need to
provide further direction to staff as to the types of "uses" that would be prohibited under the
proposed interim ordinance.
Another important effect of the proposed moratorium is the impact on the City's ability to
process new discretionary development applications for properties within the area covered by the
interim ordinance. Even though the ordinance would prohibit issuing building permits because
of the expressed circumstances that have lead to the adoption of the interim ordinance (the facts
that are set forth in the recitals of the ordinance), those same facts have to be considered by staff
when evaluating projects for completeness and for compliance with CEQA. In other words, the
same reasons for adopting a moratorium on new building permits (for example, the recent
storms, the need to complete further hydrological analysis, the effect that any new hydrological
analysis may have on land use recommendations in the new General Plan) will result in the
inability to process new discretionary development applications. This inability is created by the
lack of adequate information on which to determine whether the project can comply with
existing floodplain development policies or with applicable provisions of CEQA. The impact of
the moratorium may then be significantly broader than the Council may have intended.
Attachments: Storm inundation and 100 -year Floodplain exhibit
Correspondence to Sonoma County regarding zero net fill (2 letters)
5
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This exhibit reflects Floodplain and
I', Floodway boundaries from the Sept
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1989 FIRM; it does not reflect any
subsequent changes from LOMRs or
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Flood Line
Flood Line (no photo)
Inundated Area i4' "'Z le,
Floodplain 100yr
City Limit
7 August 2003
County of Sonoma
Permit and Resource Management Department
2550 Ventura Avenue
Santa Rosa, California 95403
Sonoma County General Plan Update 2020
Citizens' Advisory Committee
RE: Public Safety Element
Flood Hazards
Dear Planners and Citizens' Advisory Committee Members:
Thank you for the opportunity to review and comment upon the work
undertaken for the preparation of the updated General Plan Public Safety
Element. The City of Petaluma respects, and appreciates, the effort that has
gone into addressing the flood hazards within the Petaluma Watershed. As both
the County and City are currently updating our respective General Plans, it is
timely and appropriate to synchronize our watershed management approaches to
insure implementation is undertaken to adequately address the needs of the
existing channel corridors and anticipated increases in storm flows.
We have reviewed the June 19, 2003 memo prepared by PERMD, and offer the
following comments for your consideration:
1. (page 2) Petaluma River. Descriptions of the Petaluma River
main areas of significant flooding reference the "Payran Area
Floodplain". It is noteworthy to mention here that many of the
homes built in the 1960s in this neighborhood were actually built
in the regulatory Floodway (rather than Floodplain).
2. (page 8) Zero Net Fill Ordinance. We enthusiastically support
the reference to requiring "zero net fill" to the floodplains of all
streams. The implementation of zero net fill is the minimum of
development standards that should be applied to development
that directly attributes to increasing downstream flows. The City
of Petaluma has, in the past, requested that zero net fill be applied
to all floodplain areas feeding into the Petaluma Watershed
within or upstream of the City.
Sonoma Coomo, PERMD
Citiseas' Advisory Committee 8 August 2003
Re: General Plan 3020—Public Safehr Elemeat— Flood Hazards Pave 2
3. (page 12) Stormwater Runoff. The information on increases to
impervious surface area in the relatively rural County areas, and
the companion increased runoff volumes, appears to disconnect
completely from the fact that the increased runoff from even rural
or semi -rural development can cumulatively be significant when
received by an already constrained or impacted urban
environment. downstream. Runoff that is insignificant within an
individual sub -basin becomes very significant when combined
with other sub -basins and enters a major watercourse. For
example, the runoff that enters the City of Petaluma at the
northernmost corner is the combined flows of sub -basins served
by Willowbrook, Lichau, Cold Springs and Davis Creeks (and
other minor creeks). The runoff conveyed from development
within each of these sub -basins into open channels and/or local
pipe systems generates flows toward the Petaluma River more
quickly, generally creating higher peak flows than runoff
conveyed through natural streams or through vegetation.
The closing sentence reads "...the figures also show the need to
begin to address impervious surface areas in urban areas." This
is critically important when the County urban areas are in close
proximity to urban areas with significant history of flooding.
Consistent Watershed planning, watershed management, and
watershed mitigation implementation must be the approach
embraced by both the City and the County. This cohesive,
coordinated approach was referenced in the summary of verbal
and written comments received at your community outreach
workshops (page 4 of memo).
The mostly adversely affected area, within a specific watershed,
should be respected in setting development standards and long-
term mitigation measures to address cumulative flooding impacts.
4. (page 12) Strategies for Reducing Stormwater Runoff - Low
Impact Development. We appreciate the inclusion of this
discussion and look forward to their inclusion in the new 2020
General Plan policies and programs for implementation. We
respectfully request that this include the analysis of changes to
the "timing" of increased or modified runoff. Analysis of
cumulative impacts of flows, when combined with other sub -
basins, and the resultant change of peak flows in downstream
flood prone areas should be factored into the watershed
management approach.
r+
Sonoma County PERDID
Citizens' Advisory Committee 8 August 2003
Re: General Plan 3030 —Public Safen, Element— Flood Hamrds Pave 3
5. (page 13) New Clean Water Act Requirements. Although the
Petaluma Watershed does not fall into the same category as the
Santa Rosa Watershed under the Federal Clean Water Act and
National Pollutant Discharge Elimination System Permit
requirements, some reference to the standards applicable to this
watershed would be appropriate, and appreciated. The context in
which the County urbanized areas within the Petaluma Watershed
affects the City's ability to meet regulatory standards could be
discussed.
6. (page 14, second paragraph) Stormwater Runoff Detention
Ordinance. The City of Petaluma General Plan now being
prepared will be 2004 — 2025 (not 2000-2020 as referenced).
Please reference the Petaluma River Access and Enhancement
Plan within the context of this discussion. Adopted in 1986, this
Plan recognizes that while it does not serve as a flood control
plan, it does propose environmental enhancement and public
access and education improvements, which are coordinated with
the Petaluma River Watershed Master Drainage Plan. Proposed
improvements include realigning upper bank areas to create flood
terraces to increase channel capacity and reduce out -of -bank
flooding.
7. (page 14) Petaluma River Flood Control Activities. Please
recognize that "All of the repetitive loss properties in Petaluma
currently on FEMA's list are located in the Payran Area
Floodwav and Floodplain". The distinction between the two
regulatory designations is important. By far, the most severe
flooding has been suffered upon the homes within the Floodplain.
Petaluma contains a number of developed properties within the
Floodplain that have not sustained flooding, due to adopted City
development standards.
It is appropriate, at this point within the report, to discuss the
subject of watershed based flood mitigation solutions and a
reasonable proportionate fair -share approach to funding those
improvements. Cumulative stone flows, which have historically
flowed from the surrounding rural lands, differ in volume and
velocity from the flows now entering the City river system. This
cumulative increase in flows calls for curnulative solutions.
8. (page 17) Option Lb. Expansion of the term "coordination" to
define specific policies and development standards is warranted.
Although the Petaluma River does not compare to the Russian
Sonoma Comtg,PERAID
Citizeos' Adnisou Committee 8 August 2003
Re: General Plan 2020 —Public Safeh, Element—Flood Harards Paee d
River in volume, term, intensity, repetitive loss, value of
damages, or number of people affected, the people and property
adversely affected by cumulative storm flow increases in
Petaluma feel just as devastated as those in the Russian River
watershed when evacuation occurs during a storm event. Real
solutions are needed, with timelines and prioritization, to insure
timely implementation.
9. (page 18) Options 3 and 4. The City supports these options,
particularly if Option 4 is directed toward areas that are located
within watershed already impacted by downstream flooding.
10. (page 18) Policy PS -2c. Please include the City Surface Water
Master Plan and the Petaluma River Access and Enhancement
Plan. These two documents, when combined with the Petaluma
River Floodplain Management Plan, can achieve long-term flood
reduction and enhancement of the River corridor as a south
county asset rather than a liability.
11. (page 19) Policy PS -2g. As worded, this policy does not address
downstream impacts, only those areas "subject to flooding". As
proposed, the issues have once again been disconnected from
downstream conditions. Development of a parcel may
significantly impact downstream conditions and increase
potential or actual flooding, but not specifically be "subject to
flooding" itself. Please consider rewording the policy to require
compliance to "zero net fill" for any floodplain property, which
drains to a sub -basin or watershed, which is subject to flooding.
12. (page 19) Policy PS -2i. We applaud the content of this policy,
and those who stand for the long-term benefits and
accomplishments that could be achieved through its
implementation.
However, we suggest that this be expanded to adopt an
Ordinance that would apply to all permits, not just discretionary
review projects, so that a truly cumulative solution can be shared
and implemented by all. Every parcel that develops within the
Petaluma Watershed contributes to downstream flows, unless on-
site retention is implemented; therefore, every developing parcel
can be a partner in implementing the long-term solution.
Applying a proportionate fair -share of the solution would not be
cumbersome or arbitrary, but based on fairness and
appropriateness.
Sonoma Coant)+ PERMD
Citizens' Advisory Committee 8 August 2003
Re: General Plan 2020— Public Safeco Element —Flood Hazards Pave 5
13. (page 20) Policy PS -2n. This policy touches upon the
discussion above (Comment #12), but does not clearly include
off-site and downstream drainage system needs. This policy
should address cumulative down -stream impacts.
Thank you, again, for the opportunity to participate in this process. We look
forward to the successful implementation of the projects we currently have on
the preliminary design table and to the projects yet to be designed and
implemented. Both the County and the City have substantially invested in
studies and plans, combining those Plans and our resources will achieve the
adopted goals of both agencies and will serve our citizens in protecting and
enhancing their quality of life.
Sincerely,
Pamela A Tuft, AICP
Director of General Plan Administration
c: Supervisor Mike Kerns, Sonoma County
Mike Bierman, City Manager
Mike Ban, Interim Director, Dept. of Water Resources & Conservation
Lisa Posternak, PERMD
SoCo GP2020 work file
PT/rf
H:pVcorres\SoCo GP CAC flood hazards 080703.doe
11
4 September 2003
County of Sonoma
Permit and Resource Management Department
2550 Ventura Avenue
Santa Rosa, California 95403
Sonoma County General Plan Update 2020
Citizens' Advisory Committee
RE: Public Safety Element
Flood Hazards
Dear Planners and Citizens' Advisory Committee Members:
Thank you for your consideration at the last CAC meeting and your support for
addressing the upstream impacts within the Petaluma Watershed affecting the
flood hazards within the City of Petaluma. The City of Petaluma continues to
respect, and appreciate, the effort that has gone into addressing the flood hazards
within the Petaluma Watershed by the Permit and Resource Management
Department staff.
We have reviewed the September 4, 2003 memo prepared by PERMD, and offer
the following cornments for your consideration:
• (page 8) Proposed "Policy PS -2c" The wording, as proposed, reads,
"Cooperate with the City of Petaluma on implementation of the Petaluma
River Floodplain Management Plan". While we appreciate the stated
intent to cooperate, the City respectfully requests that you include a
program to adopt an Ordinance to require compliance to "zero net fill"
requirements for all development within the floodplains of all streams
feeding into the Petaluma Watershed. The implementation of zero net
fill is the minimum of development standards that should be applied to
development that directly attributes to increasing downstream flows.
l2-
Sonoma County PERMD
Citizens' Eldvisoiy Committee 4 September 2003
Re: General Plan 2020—Public Safen, Element — Flood Hazards Pave 2
As we stated in our previous communication to the CAC, the information
in the prior PERMD report on increases to impervious surface area in the
relatively rural south County areas, and the companion increased runoff
volumes, appears to disconnect from the fact that the increased runoff
from even neral or semi -rural development can cumulatively be
significant when received by an already constrained or impacted urban
environment downstream. Runoff that is insignificant within an
individual sub -basin becomes very significant when combined with other
sub -basins and enters a major watercourse. For example, the runoff that
enters the City of Petaluma at the northernmost corner is the combined
flows of sub -basins served by Willowbrook, Lichau, Cold Springs and
Davis Creeks (and other minor creeks). The runoff conveyed from
development within each of these sub -basins into open channels and/or
local pipe systems generates flows toward the Petaluma River more
quickly, generally creating higher peak flows than runoff conveyed
through natural streams or through vegetation. The mostly adversely
affected area, within a specific watershed, should be respected by setting
development standards and long-term mitigation measures to address
cumulative flooding impacts.
Request: Expansion of the term "cooperate" in the recommended
wording for Policy PS -2c, to provide a specific policy to Adopt
Ordinance requiring zero net fill in all floodplain areas.
• Storm Drainage Impact Fee: It is appropriate to discuss the subject of
watershed based flood mitigation solutions and a reasonable
proportionate fair -share approach to funding those improvements.
Cumulative storm flows, which have historically flowed from the
surrounding rural lands, differ in volume and velocity from the flows
now entering the City river system. This cumulative increase in flows
calls for cumulative solutions.
The City of Petaluma has implemented a Storm Drainage Impact Fee for
all new development, regardless of location within a Floodplain. These
one-time fees are utilized to fund regional serving flood reduction
projects. The implementation of a storm drainage impact fee for the
unincorporated areas within the Petaluma Watershed would allow the
funds to be designated to specific projects throughout the watershed for
addressing the cumulative impacts of additional development.
13
Sonoma Coanh, PERAID
Citizens' ddrismy Committee 4 September 3003
Re: General Plan 2020—PnblicSafeh,Element— Flood Haaards Page
We recognize the existence of Zone 2A assessments, currently due to
sunset in a few years. The City Management team supports the
continuing need for this assessment, beyond the sunset period.
Request: Add Policy to provide for Adoption of a Storm Drainage
Impact Fee for all new development within the Petaluma Watershed.
• Policy PS -2e. Thank you for including the City Surface Water Master
Plan and the Petaluma River Access and Enhancement Plan in this policy
statement. These two documents, when combined with the Petaluma
River Floodplain Management Plan, can achieve long-term flood
reduction and enhancement of the River corridor as a south county asset
rather than a liability.
• Policy PS -2g. The September 4 staff report does not readdress
amendments to this proposed Policy. As originally worded, this policy
did not address downstream impacts, only those areas "subject to
flooding".
Request: If not amended, please consider rewording the policy to
require compliance to "zero net fill' for any floodplain property,
which drains to a sub -basin within the Petaluma Watershed
• As above, the September 4th report does not readdress Policy PS -2i. We
applauded the content of this policy, and those who stand for the long-
term benefits and accomplishments that could be achieved through its
implementation. Every parcel that develops within the Petaluma
Watershed contributes to downstream flows, unless on-site retention is
implemented; therefore, every developing parcel can be a partner in
implementing the long-term solution. Applying a proportionate fair -
share of the solution would not be cumbersome or arbitrary, but based on
fairness and appropriateness.
Request: We again suggest that this be expanded to adopt an
Ordinance that would apply to all permits, not just discretionary
review projects, so that a truly cumulative solution can be shared
and implemented by all.
To clarify a question from the CAC regarding the City zero net fill regulations:
The City currently requires any development within a floodplain combining
district property comply with the zero net fill requirements. Properties not
_14
Sonoma County PERAID
Citizens' Adidsory Committee 4 September 2003
Re: General Plan 2020 — Public Safety Element —Flood Hazards Pave 4
encumbered by the floodplain -combining district are not subject to the zero net
fill requirements.
Thank you, again, for the opportunity to participate in this process. We look
forward to the successful implementation of the flood reduction projects we
currently have on the preliminary design table and to the projects yet to be
designed and implemented. Both the County and the City have substantially
invested in studies and plans, combining those Plans and our resources will
achieve the adopted goals of both agencies and will serve our citizens in
protecting and enhancing their quality of life.
Sincerely,
Pamela A Tuft, AICD
Director of General Plan Administration
c: Supervisor Mike Kerns, Sonoma County
Mike Bierman, City Manager
Mice Ban, Interim Director, Dept. of Water Resources & Conservation
Lisa Posternak, PERMD
SoCo GP2020 work file
PT/rf
H:pUcorres\SoCo GP CAC Mood hazards 090403.doc
1s