HomeMy WebLinkAboutAgenda Bill 4.B 05/16/2011DATE: May 16, 2011
A ge + wLal Ibe4 V #4.B
TO: Honorable Mayor and Members of City Council through City Manager
FROM: Pamela Tuft, Interim Director, Department of Water Resources and Conservation
SUBJECT: Resolution Accepting the Stormwater Program Funding Evaluation Report
RECOMMENDATION
It is recommended that the City Council adopt the attached Resolution Accepting the Stormwater
Program Funding Evaluation Report.
BACKGROUND
In April 2010 the DWR &C sought. Proposals from consulting firms to conduct a focused
evaluation of the City's stormwater management program. and to quantify the benefits it provides
to the wastewater utility. This analysis was sought, in part, to answer questions regarding
whether it is appropriate to use Wastewater Utility funding to support the costs of storm drain
and storm water system maintenance. The analysis is also intended to discuss the sufficiency of
the City's storm water system, to identify improvements to optimize its effectiveness and to
discuss options for funding such improvements.
The firm of HDR was selected from the respondents to the Request for Proposals and a contract
was executed.
DISCUSSION
The attached report reflects HDR's investigation, data collection, evaluation of the City's
pr p a nd funding; and
stormwater ro ram, com anson of other cities' stormwater functions a
preparation of conclusions and recommendations. Among HDR's conclusions is the following
which can be found on page 31 of the report:
"HDR believes the City's current funding of SWP costs through sewer rates is
appropriate and meets the requirements of both cost of service principles and Prop
218...."
The report provides the analysis and conclusion as defined, by the scope of work and contract.
The report also defines alternative stormwater funding mechanisms available to the City should
Agenda Review: no
City Attorney Finance Director City Manager�� 1
interest exist on providing a new funding source and/or a separate utility to cover the costs
associated with existing or expanded stormwater services.
At present, there is no funding source for existing property owners to participate in local and
regional stormwater management solutions. The creation of a separate stormwater utility or
parcel fee to fund capital improvements could assess the benefits of flood reduction and water
quality projects either City -wide or, if done in concert with the County, on a watershed -wide
basis. As stated in the Report (page 32), this can be a "complicated, time- consuming, and costly
endeavor" and is not suggested for consideration before undertaking community outreach into
the possibilities and options.
Should the Council indicate interest in researching the feasibility of creating a stormwater utility
and associated funding options, City staff would conduct the necessary investigation. If the
Council wishes to continue to provide the current level of stormwater services, then continuing
to do so through the Wastewater Utility Funds is a more reasonable and cost - effective approach
(pages 28 -32 of the Report).
FINANCIAL IMPACTS
There are no financial impacts associated with accepting this Report. If the Council agrees with
the conclusions of the Report, limited stormwater activities will continue to be contained in the
sewer enterprise budget and relevant to future wastewater rate - setting activities. It should be
noted approximately 2% of a typical wastewater customer's bill is currently estimated to go to
stormwater program services functions. DWR &C staff will continue to pursue avenues of
stormwater program funding outside of the Wastewater Utility fund such as SCWA — Zone 2A
special project funding and grants to fund flood reduction improvements within the community
and the watershed. The Report may also provide an informational and analytical basis for other
future funding and resource activities related to the stormwater policies, activities and facilities
evaluated in the Report.
ATTACHMENTS
1. Resolution
2. City of Petaluma Stormwater Program Funding Evaluation Report (HDR, April 2011)
2
Attachment 1`
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Resolution Accepting the StormwaterTrograrn
r '
2
Funding Evaluation Report
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WHEREAS, the, City of Petaluma conducts operation and maintenance activities to
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ensure the °function of the community's storm drainage system; and,
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WHEREAS, in 2010 the City Council directed staff of the Department of Water
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Resources and Conservation to undertake an evaluation of the'funding mechanisms for
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conducting the City "s stormwater program; and
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WHEREAS, in September 20 the City hired HDR, Inc. to undertake the evaluation;
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and
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WHEREAS, in consultation with. City ,staff, HDR has produced the City of Petaluma
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Stormwater Evaluation Report (April 2011), "the Report" which studies and evaluates the
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current stormwater program system deficiencies and planned improvements, funding
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mechanisms and other agencies' systems; and
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WHEREAS. the City's ., stormwater facilities help meet, `the primary :sewer system
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objectives, including protecting the quality of surface,water and groundwater; and
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WHEREAS, wastewater : rates including the stormwater funding component,. have been
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and will continue to be adopted .bythe City through a public hearing process which meets
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the notice . and substantive :provisions of applicable law, including but not limited to
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Proposition 218; and
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WHEREAS, stormwater facilities protect wastewater system, customers by providing
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flood reduc tion protection p „ori - by reducing sanitary sewer .overflows and the .severity of
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flooding during peak storm events; and
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WHEREAS, maintenance. of City stormwater facilities, ,. and the reduction of
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inflow /infiltration reduces the demand' on the wastewater collection and treafrnent system
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byreducing "the amount of flow through the City's treatment' facilities; and
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W HEREAS', the. Report .. concludes that the -portion of the stormwater program funded by
a rates 'through the W'astewat'er Utility :Fund, estimated currently as
a
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a rox mately two percent (2 ° /0) of a typical customer's'bill, pays for services essential to
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the functioning of the wastewater system, and that said services, if not performed by the
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stormwaterprogram, wo'uld.increase costs to the Wastewater Utility Fund, and
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WHEREAS,, the Report further concludes that the current process for apportioning some
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stormwater program costs to the Wastewater Utility Fund meets the requirements of both
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cost of service principles, and Proposition 218 nexus requirements because th:e funded
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activities provide special 'benefit to the customers paying wastewater charges" and fees
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and do not ekceed the cost of providing the funded services.
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NOW, THEREFORE, BE IT RESOLVED BY THE CITY COUNCIL OF THE
CITY OF PETALUMA AS FOLLOWS.:
1. The above recitals are an accurate reflection of the City of Petaluma Stormwater
Program Funding Evaluation (HDR, April 2011) (the "Report") contents and
analysis relating to funding of some stormwater program costs by the Wastewater
Utility Fund.
2. The Report is accepted as a.document providing information and analysis relevant.
to (i) the allocation of certain Wastewater Utility Fund resources to the operation
and maintenance of the City's stormwater system; (ii) future wastewater rate -
setting actions by the City; and/or (iii) .other future funding and resource activities
related to the stormwater policies, activities and facilities evaluated in the Report.
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Cit,Of P6tAMa
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2365 Iron Point Road
Suite 300
Folsom, CA 95630 -8709
016.817.4700
www.hdrinc.com
City of Pet
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April 2011
Pamela Tuft
Interim Director
Department of Water Resources & Conservation
Remleh Scherzinger, P.E.
Engineering Manager
Greg Clumpner
HDR Project. Manager
Holly Kennedy, P.E.
HDR'Utilities Group Manager
License No. C74682
2121 N. California BI. Ste. 475
Walnut Creek, CA 94596
TABLE OF CONTENTS
Table Contents ................................................................................ ............................... i
Listof Tables ........................................................................................................ ............................... iii
List of Figures ..................,
........................................................ ............................... ............................ iii
Listof Acronyms .................................................................................................. ............................... iii
S ection 1 - Overview and Summary ...................................................... ..............................1
1.1 The Current SWP Funding Mechanism ................................................. ............................... 1
1.2 Proposition 218 Requirements ................................................................. ...............................
1
1.3 Future Funding Needs .............................................................................. ...............................
2
Section 2 - The Current Stormwater Program ......................................... ..............................3
2.1 Description of the Existing Stormwater Program and Facilities ........ ...............................
3
2.1.1 Watershed and Service Area ............................................................ ...............................
3
2.1.2 Major Stormwater Facilities ............................................................. ...............................
5
2.1.2.1 Channel and Other Conveyance Infrastructure .................... ...............................
7
2.1.2.2 Pumping Stations ....................................................................... ...............................
7
2.1.2.3 Ellis Creek WRF .......................................................................... ...............................
8
2.1.3 Related Stormwater Policies and Practices ................................... ...............................
8
2.1.4 Stormwater Program Costs .:............................................................ ...............................
9
2.2 Stormwater Program Benefits and Beneficiaries ................................ ...............................
10
2.2.1 Flood Protection ................................................................................. .............................10
2.2.2 Wastewater Collection and Treatment ......................................... ...............................
11
2.2.3 Protection of Groundwater and Surface Water Quality ............ ...............................
11
12.4 Protection of Wildlife Habitat, Fish and Aquatic Species .......... ...............................
12
2.25 Benefits to Other Agencies ............................................................. ...............................
13
2.3 Current Program Funding Mechanisms .............................................. ...............................
15
2.3.1 Current Funding Sources ................................................................. .............................15
2.3.2 Current Rate Structure .................................................................... ...............................
15
Section 3 - Stormwater Program Deficiencies and Planned Improvements ...........................17
3 .1 System Deficiencies ................................................................................. ............................... 17
3.2 Planned Improvements .......................................................................... ............................... 18
. ; .......
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3 .2.1 Drainage Channels .......................................................................... ............................... 18
3.2.2 Regional Detention Facility .............................................................. .............................18
3.2.3 Payran Flood Control Project ........................................................... ..........:..................18
3.2.4 Development Specific Detention Facilities ...:................................ .............................18
3.2.5 Maintaining Hydraulic Capacities ................................................ ............................... 19
Section 4 - Stormwater PrograrnFunding Evaluation ....... .....:.....,....... , .............................. . 20
4.1 Basis for Evaluating Funding Mechanisms ......................................... ...............................
20
4.1.1 General Rate Setting Criteria ......................................................... ...............................
20
4.1.2 Industry -Wide Rate Fundamentals ............................................... ...............................
21
4.1.3 Rate Setting and'Cost -of- Service. Principles ................................. ...............................
21
4.1.4 Proposition 218 Requirements ....................................................... ...............................
22
4.2 Alternative Stormwater'Fundiing Mechanisms ................................... ...............................
22
4.2.1 Current and Historical Funding Practices ................................... ...............................
22
4.2.2 Discussion of Industry Standards for Funding Stormwater Programs ..................
23
4.2.2.1 Western Kentucky University Survey ................................... ...............................
24
4.2.2.2 Black & Veatch Survey ............................................................ ...............................
24
4.2.3 Case Studies of. Stormwater Rates ................................................. ...............................
25
4.2.3.1 City of Santa Rosa, California ................................................ ...............................
25
4.2.3.2 City of Vallejo, California ....................................................... ...............................
26
4.2.3.3 City of Salinas, California ....................................................... ...............................
26
4.2.3.4 Sacramento County, California .............................................. ...............................
26
.4.23:5 Bakersfield, California ............................................................. ...............................
26
4.2.3.6 City of Portland Oregon ......................................................... ...............:...............
26
4.2.3.7 City of Issaquah, Washington ......................... I..................
27
4.2.3.8 City of Kitchener, Ontario, Canada ....................................... ...............................
27
4.2.4 Alternative Stormwater Funding Mechanisms ........................... ...............................
28
4.2.4.1 A Separate Stormwater Utility ............................................................... I..............
28
4.2.4.2 Impervious Surface Area -Based Fees .................................... ...............................
29
4.2.4.3 Funding From Related Agencies ........................................... ...............................
29
4.2.4.4 Stormwater Fee Collection Methods ..................................... ...............................
30
4.3 Analysis of Beneficiaries and Equity .................................................... ...............................
30
4.3.1 Basis for Funding Stormwater Program with Sewer Funds ...... ...............................
30
4.4 Conclusions ............................................................... ...............................
4.4.1 Reasonableness of Using Sewer Rates to Fund the City's SWP
4.4.2 Other Funding Options for SWP Capital and O &M Costs........
........................... 31
........................... 31
........................... 32
List of Tables
Table 1 - Current Petaluma Sewer Rates ............................................................. ............................... 16
Table 2 - Summary of Broader Funding Mechanisms Applied to Stormwater Programs.......... 20
List of Figures
Figure 1 - Area Surrounding the City's Watershed ............................................. ............................... 4
Figure 2 - City's Stormwater Collection Facilities ....... ............................... ....... ............................... 6
Figure 3 — Map of Petaluma Basin Zone'2A .........................................:............... .............................14
List of Acronyms
AWWA American Water Works Association
BMP
Best Management Practices
DWR
State Department of Water Resources
ERU
EquivalentResidential Unit
FEMA
Federal Emergency Management Agency
hcf
hundred cubic feet
HDR
HDR Engineering; Inc. (Consultant to the City)
I/I
Infiltration Inflow
ISA
Impervious Surface Area
NPDES
National Pollution Discharge Elimination System
O &M
Operations and Maintenance
RCD
Resources Conservation. District (for Southern Sonoma County)
RWQCB
Regional Water Quality Control Board
SCWA
Sonoma County Water Agency
SSO
Sanitary Sewer Overflow
SWMP
Stormwater Management Plan
SWP
Stormwater Program (City of Petaluma's)
WRF
Water Recycling Facility (the Ellis Creek WRF)
Zone 2A
Petaluma Basin Zone 2A
07685 - 150338 -0128
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The City of Petaluma (City) retained HDR Engineering, Inc., (HDR) in September 2010 to evaluate
the City's approach to funding its stormwater program (SWP), including the City's current
funding mechanism through sewer rates as well as potential alternative funding mechanisms.
This report provides an overview ofthe City's
stormwater facilities and discusses planned capital
improvements needed to maintain and /or improve
drainage channel hydraulic ; capacities. However, the
primary purpose cifthis report is to evaluate whether
the use of the City's current SWP funding mechanism
is reasonable and appropriate. In addition, HDR
evaluated other funding mechanisms for funding
future SWP costs, as well as mechanisms specific to
future operating and capital improvements.
1.1 The Current SWP Funding Mechanism
While there is not broad consensus within the industry on who should pay for stormwater
program costs or what type of rate structure 'should be used. HDR ha`s concluded that the City's
current funding of its stormwater program through sewer rates can be justified based on the
benefits to sewer customers. These benefits include:
Reduced sewage collection and treatment costs.
Protection of surface water and groundwater.
Flood control.
Broader environmental benefits, such as protection and enhancement of fish and wildlife
habitat.
1.2 Proposition 218 Requirements
Regarding concerns about, fairness, equity, and,subsidies
under Califomia's Proposition 218: regulations, HDR
believes, the sewer rate revenue used to pay for a portion
of stormwater activities is an appropriate use of sewer
funds, does not create subsidies, and is a fair and
equitable means of charging City residents for
stormwater program costs. This position is based on a
review of industry practices, methodologies used by
similar sewer /stormwater utilities, and basic cost -of-
service principles. Also, SWP costs make up approximately 2% of the typical sewer customer's bill,
and in light of this, funding SWP costs through sewer rates is cost- effective and serves the City's
residents and businesses well.
CE g
07685 -' 50338 -028 1
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Forming a separate stormwater .utility with a service area covering, areas outside the City's
sewer service area that;,also,benefit from the City's SWR
Developing anew rate structure, such as impervious surface area -based fees.
ED Expanding joint funding opportunities from adjacent.agencies such as the Sonoma County
Water Agency (SCWA).
The following sections discuss the current stormwater program (Section 2), deficiencies of
stormwater facilities.and planned improvements (Section 3,), and the evaluation of stormwater
funding mechanisms (Section 4).
• e: • e e e:e e
The City's.SWP is similar to many other California communities;in that it has historically been a
very small operation, which typically included vegetation control and debris removal from
stormwater catchbasins and drainage channels. Many older . communities, including Petaluma,
have at one point-had a "combined" sewer and stormwater collection system.
The actual City boundaries encompass an area of approximately 116 square- miles, including hills
to 400 feet above sea level. The open creeks and channels, and enclosed " stormwater facilities
located throughout the City convey runoff from upstream,in the watershed through the City, to .
the Petaluma River, and eventually to the San Pablo Bay, approximately 12 miles to the south.
Approximately 40 years.ago, the City made improvements
that significantly separated storm water flows from the sewer
collection system. These improvements reduced the peak
wet weather flows in the sewer system. As a result the
design capacity of the City's recently constructed Ellis Creek
Water Recycling Facility,(WRF) did'not need to include the
majority of peak wet - weather stormwater volumes.
Due to the age of the community and the °prevalence of old and degraded pipe sections, some
inflow and infiltration (I/1) will continue to enter the City`s sewer collection system, which is not
adequately sized to accommodate existing 1/1 flow volumes. This results in occasional,short -term
sanitary sewer overflows'( , SSCis) during peak storm events that exceed system capacities, primarily
in the southwestern quadrant of the community. The. City �is prioritizi-g the replacement or
sliplining of these degraded lines in order to ensure these I/I problems are being addressed in a
timely manner.'
The :City's stormwater system lies within the Petaluma River Watershed, which covers
approximately 146 square miles. This watershed is geographically a large bowl bounded by the
Sonoma'MOuntains to :the east and a range of low hills to the: west,,all of which drain into; the
Petaluma River. Figure 1 is a map of Sonoma County's NPDES Phase Il Permit boundaryrshow ng'
the area surrounding the City's watershed; this provides context to the relationship between'the
City's boundary, adjacent communities, and the San Francisco -Bay.
The outer boundaries of the City's stormwater system and facilities are essentially the City's urban
growth boundaries, an area of approximately 16.1 square miles. Additionally, many of the areas
outside the City are, at least:in some fashion, served'by'the City's stormwater program. For
example; the unincorporated Penngrove .area, which is to the northeast and immediately
"upstream-" from the City`in the floodplain, passes stormwater runoff directly into the City's
stormwater facilities.'
' Several,classes of rehabilitation techniques could be used, most notably sliplining and cured -in -place pipe (CIPP) lining.
2 This is confirmed by the rain gage "has,established and now maintains in Penngrove. ,
_....
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There are also several smaller drainage areas inside City limits that cross the City's urban growth
boundaries into unincorporated 'areas before returning to the City limits and entering the Petaluma
River. The same;circumstances exist for the. Liberty /Marin/Wiggins drainage basin where
stormwater flows quickly across and through agricultural lands to enter the Petaluma River at. the
northern City limits. As; a result, the City's stormwater facilities help reduce flooding in areas west
of Petaluma and in Penngrove "by accommodating
passage of those flows downstream,
4 City of Petaluma, Annual Report, General Permit for Discharge of Storm Water from Small Municipal Separate Storm Sewer Systems (MS4's),
September 20b9, p. 13.
Q i 68 - 50338 -028 ..r
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5 •Adapted from Figure 8- 1,100 -Year Flood Boundary, from the; City's General Plan 2025.
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0 7.6 8 5 . 50338 0 28
There are approximately 20 miles of open channels and,natural creeks within the City and
approximately 70 locations where open channel flows are,conveyed underneath roadways by
means of bridges or culverts. The Petaluma River flows.through nearly 7 miles of open corridors
andl bridges within the City limits.
°9, 2, ¢ h nnel -acrd O tkDr Conveyan� e Jn rasfr°uc, n r
Many of the City's natural waterways and creek channel banks have been constructed or modified
using, biotechnical and bioengineered, methods•including riprap, fl'oodwalls, concrete lining, open
half- culverts, and covered pipe.. Maintaining adequate flow capacities within;the channels to
provide maximum containment and conveyance of peak storm 'r'unofHs key to the effectiveness of
the City's existing stormwater drainage system.
In addition to the open channels,Ahere are approximately -40 miles of storm drainage pipe with
diameters ranging from 8 to 80. inches. There are also approximately 3;475 storm drain inlets, or
catch basins, that funnel stormwater into the City's drainage, system. The drainage system also
includes ap 1.7 miles of roadside dit ches, which direct runoff to an open: creek or
enclosed pipe
The City's stormwater coll'ectionsystem has
three pumping stations. One of the most critical
components of the system is the Wilson Street
Pumping Station, which is essentially at the
bottom of the drainage'syste_m. This pump
station collects stormwater flows from four'36
inch - diameter pipelines and conveys them from
the southern half of "the older eastsid'e
neighborhoods into the McNear Channel. These
flows then run directly into the. Petaluma River.
In 1996, the City determined that overflow has three pumping stations.
problems in the, - sewer collection, system were
primarily due, to limitations; inr,the pumping capacity of the City's wastewater primary influent
pump station (PIPS),"' as well as an undersized Lindberg.Lane sewer. main. To help reduce 'these
sewer system overflows, the PIPS was upgraded; and expanded in 2001 to its current capacity of 36
mgd, and the Lindberg Lane main was replaced in 2002 to befte'r,handle peak wet weather flows.'
6 More detailed descriptions and inventories of these "facilities, are documented in the City's 2002 environmental study, including TM3 of,the City's
General Plan EIR Appendix
7 City of Petaluma, NPDES Permit No. CA0037810, Order No. R2- 2011 -0003.
r, ..
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50138 -028 7
The City's•stormwater collection system
The City's recently- completed Ellis Creek WRF was
designed to provide'treatment of wastewater for
projected'buildout of the community,. including a
reasonable expectation of a portion of stormwater
runoff due to I /I. While,PIPS is designed to handle a
maximum of 36 mgd during peak- the WRF was
designed to process 5 mgd on a daily basis for tertiary
treatment. However, it was ' not designed to handle
peak wet - weather storm flow's when they occur.
Rather,.peak wet weather flows above the maximum
design capacity of the WRF are conveyed to storage
ponds for primary treatment, and, then returned to the
WRF for treatment at a later time.
The WRF also includes approximately 7 acres of enhanced and seasonal wetlands in the treatment
process. The , gradual movement:,of'treated wastewater and stormwater flows over these wetlands
further polishes these flows prior to seasonal discharge into the tidal mudflats and ultimately the
Petaluma.River. This process provides an additional water quality benefit to the overall
wastewater and stormwater systems and their beneficiaries.
The City's General Plan goals, policies, and•programs address other stormwater management
practices with the objective of protecting and recharging the City's groundwater resources. For
example, the City's guidelines4or new construction place restrictions on coverage by impervious
materials and building footprints, and require on- site.percolation ponds and surface drainage
swales be considered within areas defined as having groundwater recharge potential. These
guidelines support other policies - adopted for the purpose of reducing flooding'and promoting
groundwater recharge.
The City's. General' Plan also defines storm drainage standards as follows:"
10 -year. storm, events —The entire area needs to drain into a pipe or open channel.
25 -year storm events — Runoff can pond in streets.
100 - year storm events (six inches or more of rain within 24 hours) —Needs to stay out of
habitable areas (structures, residences, etc.).
Also, with the goal of`reducing water pollution and increasing groundwater recharge, the City's
sustainable site planning practices attempt to detain, filter treat, and reduce runoff to reduce the
stormwater - related impacts of new development on wildlife habitat and aquatic species.'
8 City General Plan, p. 8 -15.
9 City General Plan, p. 8 -21.
07685 503318 :.'128
The recently- completed Ellis Creek
Water Recycling Facility conveys peak
wet - weather storm flows to storage
ponds for later treatment.
i '-
=211111 111y,
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,33 1,14A
Funding for the City's SWP currently includes approximately $820,000 inannual operating and
maintenance (O &M) costs paid.by the City's sewer rate payers. The stormwater program covers
personnel costs for three full -time equivalent positions, one vacuum truck, limited ongoing
maintenance, but virtually no capital improvement costs. The City's recent Water and Wastewater
Financial Plan and Rate Study projected annual stormwater program costs would gradually increase
to approximately$915,000 by FY'14- 1`5. Since this is merely a projection of current funding levels,
it does not reflect an adequate level of storm drainage channels and-creeks or needed capital
improvements. However, failure tomaintain current hydraulic capacities of the storm drainage
facilities will likely result in more:_flooding during peak storm events; higher future maintenance
costs, catastrophic capitalxeplacement costs, and eventually higher °treatment costs for handling
higher I/1 levels at the WRF.
The City stormwater program,currently funds
minimal maintenance activities, such as clearing
stormwater collection basins, vegetation and debris
removal, from specific drainage culverts, and very
limited creek channel maintenance. Other annual
maintenance activities are funded with, SCWA-
managed Zone 2A funding. These activities `include
maintenance of creek channels and box culverts
covered by an SCWA maintenance easement. The
Zone 2A annual budget typically funds an amount
approximately equal to the City's annual SWP
budget.
City staff has confirmed. that current' funding
through sewer rates cannot adequately fund' all current. and projected O &M, much less planned
capital improvements.. As discussed in greater detail in Section 3, significant additional
improvements and maintenance activities, such a creek vegetation management and replacement
of stormwater conveyance pipes and culverts, remain unfunded. Unless the sewer utility
reallocated.current funds and/or increased sewer rates to provide,more funding for the SWP, the
City`will need new:revenue sources in order to adequate fund flood protection related costs that
minimizes I%I and Sanitary"Se'wer Overflows (SSO's). Additionally, the. City incurs,cleanup
related to. SSO's plus fines ,o'f up to $10,000 per day and $10 per gallon for spills above 1,000 gallon.
In 2010, the City reported six SSO's exceeding 1,000 gallons totaling 36 gallons, each caused by
I/L 11
Except for approximately 500 sewer customers in Penngrove., the City recovers a very limited
amount. from. properties or areas outside the City limits. This means that many properties and
residents,.outside City's sewer system boundaries and within the watershed are benefiting from
the City's stormwater program but are not paying for it other than the 'parcel tax paid to SCWA.
10 Water and Wastewater Financial Plan,and;Rate Study, Exhibit II -6, page 25, The Reed Group„ 10- 27 -10.
City of'Petaluma, Annual Report of SSO's for 2010, letter to California Regional Water Quality,Control`Board, San Francisco, March 29, 2011.
07685-50,338 9
Storm drainage: control structure in
creek channel.
at;.€af lct,cl�sr� €tom 1'r� rxJEircl� lt� >r
The adequacy and appropriateness of the current funding sources are discussed in,Section 2.3,
while potential new funding sources are discussed in Section 4.
2.2 St"water ' • e Beneficiaries
There arer a number of benefits, with the City's SWP and facilities, most of which are
discussed in the City's General Plan (.Chapter 8). The primary; benefits include protection of surface
and groundwater water quality, groundwater recharge flood protection, and protection of wildlife
and aquatic habitat These:benefits are discussed below, along with their relationship to the City's
current stormwater program funding mechanism (sewer rates).
s
MTI
The Petaluma River and its tributaries are subjectto,flooding when flows exceed the existing
hydraulic capacity of a given channel, which is primarily due to storrn events but can also include
tidal action (significantly high ides) during peak storm events.
Historically, the City has experienced flooding between December and „March for periods of three
to four days, with at least some street flooding, at least once per year.” Recorded flood damage
events have, occurred in 1982, 1983, 1986, 1995, 1996,1998,..and 2005.. Typically the creek channels
tributary to the Petaluma River begin to rise within hours of a heavy "storm event if the soils are
already saturated. The City's General Plan concludes that, based on historic records of flooding
and studies'by FEMA, "...it is clear that"flooding is a significant problem."
Over time, construction.of °impervious surface
areas such as parking lots,. streets,, and buildings
have reduced ;groundwater infiltration and,
resulted in,increased surface runoff..As a result,
more water is conveyed to the stormwater
collection system and the potential for flooding
and flood- related damage's has increased.
The 1989 'Federal Emergency Management
Agency (FEMA) study noted that °,urban growth
has encroached upon many segments of the
waterways; buil "dings °and homes that have been
built along'banks often limit the flood - carrying
capacity of these channels 13 Maintaining or
improving the hydraulic capacity of these areas
will provide better protection and reduce flood -
related damages.
The flood protection benefits provided by the
City's stormwater system accrue to the entire
community in the sense that street flooding, access to commercial businesses, emergency access,
12 General, Plan, page 8 -1,4.
13 City of Petaluma Floodplain Management Plan, October 4, 2010, p. 4.
_:�, �.. _
..
i 0 '076821.. 5033 8 -028
View of the turning basin (Petaluma Slough)
looking Northeast.
t
�x adr� a
traffic safety, etc., affect all members of the community. With very few exceptions, all members of
the community are sewer system customers.
I= �r
A significant storm`can result in enough I /I' entering the City's,sewer system_ that it causes a
different type of. flooding referred to as sanitary sewer overflows ,,, or SSOs. In these events, I/I
exceeds the capacity of-the sewer system and forces the combined runoff and sewage out of the
sewer pipes through manholes and cleanouts. This represents, sanitation and water
quality dangers to the community, and is exacerbated if the hydraulic capacity of stormwater
facilities is impaired.
As urban and rural development -and. historic rainfall patterns have increased, drainage system
capacities have, become impaired,.particularly creek channel capacities. The number of SSOs in
which runoff overwhelms the ,sewer system and out of manholes and /or breaks in sewer
system pipes have also increased in volume of discharge, although not in the number of locations.
In 2003; the RWQCB adopted an order requiring the City to develop and implement a sewer
system management?plan aimed at,reducing or eliminating these overflows.
From 2005 to 2008 the City reported an average of 11 SSO's per year, ranging from 16 in 2006 to
five in 2007. The last two years, the City has,reported six (in 2010),and two (in 2009). The City's
mitigation actions in response to the -SSO's include, (1) $400;000 /year in manhole rehabilitation, (2)
completion of the C Street Pump Station upgrade design, (3) cleaning of 59 miles of collection
system pipeline, and (4) repair /replacement of 14 private sew.er•laterals.
Although the City's recently corrpleted Ellis Creek WRF was
designed to process and treat a portion of stormwater flows with
the community's wastewater prior to recycling or seasonally
discharging these flows to the Petaluma River,.maintenance of
stormwaterfacilities help rninim ze.these treatment costs. Because
of this, the stormwater system's ability to. separately handle
stormwater runoff and reduce the associated I/1 is an important
benefit to sewer customers.
Therefore, reducing 1 /I avoids additional capital costs that would otherwise be needed fgt,,more
WRF treatment`capacity and.higher WRF O &M costs associated with a larger capacity facility. That
is, in addition to the costs of fines for SSO's, the total sewage treatment costs and sewer
customer bills would be,:higher without the SWP.
Prior to 1961, the City's primary water supply was local groundwater wells. Although the City
now obtains surface water supplies from Sonoma County Water Agency, it also continues to
operate and maintain local wells to meet peak demands and emergency water supply needs.
t Historical rainfall data in excess of 50 years and XP -SWMM model runs used in updating the City's FEMA floodway /floodplain maps demonstrate
an increase insainfall.
15 City of Petaluma, Annual Report of SSO's for 2010, letter to California Regional Water Quality Control Board, San Francisco, March 29, 2011.
sewage collection system Therefore, it is importanfifor the SWP to protect the City's
groundwater basin in addition to surface water bodies. This
stormwater objective directly overlaps with the wastewater
utility's_.mandate to protect these,resources.
Peak wet weatherflows.can increase 1/1 and result in SSOs, which are defined -as any overflow,
spill, release, discharge or .diversion: of untreated or partially treated wastewater from a sanitary
sewer system. t6 SSOs can be a,: significant contamination threat, to surface water and /or
groundwater. The City's SWP helps protect.both surface and groundwater sources by reducing I/I
in the sewage collection system..
With regard to surface water quality; the Petaluma River has been identified in the State's Section
303(d) list" as impaired for nutrients, pathogens, sediment, diazinon,'and, in tidal portions of the
river (only), nickel. The Regional Water Quality Control Board'(RWQCB) recently added "trash" to
the 303(d) list because it was:judged to "cause impairment to the Petaluma River. "
One of the primary objectives of Federal Clean Water Act regulations (including NPDES rules) is
to regulate stormwater discharges in order to reduce surface water pollutants and :improve water
quality. In compliance, with these regulations the City has prepared, obtained approval of, and
now operates in compliance with a'Storm. Water Management Plan (SWMP). The "City began
implementing its SWMP in 2003. The SWMP includes the City's commitment to:
Detection and elimination of illicit discharges;
Construction site stormwater runoff controls; and
Pollutionprevenfion for municipal operations.
A.funding- related objective of the City's SWMP is "...the developmen #`of a dedicated funding
mechanism" as a necessary part of ensuring water quality throughoutthe,planning'period covered
in the Citys'NPDES permit." Since the City's current stormwater program is partially funded by
sewer fees, protecting water quality by reducing pollutants carried in stormwater runoff and
reducing I/I related wastewater costs are broader benefits that residents and businesses fund
through their sewer charges.
2.2,4, Prcieciion of 'Wildlife Habitat, Fish and Aquatic Species
As,a part of an overall effort to enhance habitat values within the watershed, the City's
improvements to; and. proper maintenance of its surface water system helps protect riparian
habitats and provide necessary facilities preservation, wildlife, fish and other aquatic species.
The watershed includes several endangered: species in fhemarsh habitat of the Petaluma
watershed, including the California black rail, California clapper rail,, and the Salt Marsh Harvest
16 State Water Resources Control Board, °website ( http:// www.waterboards.ca:gov /aboUt_us /performance_ report/
plan _assessl12411 _sso_sewage_spills. shtml).
17 Clean Act section identifying impaired water bodies.
18 City of Petaluma, Annual Report, General Permit for Discharger of Storm Water from,Small' Municipal Separate Storm Sewer Systems (MS4's),
September 2009, p.6.
19 General Plan, page 8 -15,
x a
0768.5 - ?50338 -0 28
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mss. ..,., �, , i� ,w ,•.,. �. .. �.��,��.,��. a :.., �a. ,,. ,� . v�.m:: �o��..<.,_ ,'� a -�� - , s�4�
Mouse - ,21 The U:S. Army Corps.of Engineers list Chinook Salmon and, Steelhead'as endangered and
the Sacramentosplittai'l as ;'a species of concern.
Other agencie&with regulatory orjurisdictional .responsibilities in the watershed incur many of the
same stormwater program, benefits as City residents. These: agencies also actively cooperatel and
participate.in both stormwater program capital improvements and operations. These agencies
include the County of Sonoma,, SCWA, and the'Southern Sonoma County Resource Conservation
District (RCD); a'local component of the U.S. Department of Agriculture. SCWA and RCD
involvement are summarized below.
El SCWA shares responsibility for maintenance of open channels; within the City and was
involved in developing the Petaluma River Watershed Master Drainage Plan which was last
updated in June 2003 `This master plan provides guidance for development of channel
improvements, Petaluma River and tributary setbacks, and the design and construction of
flood terraces to provide passage of:large storm events.
The RCD developed the-Petaluma Watershed Enhancement Plan, and has funded projects that
provide watershed enhancement, improve groundwater recharge, land conserve and enhance
existing wildlife habitat.
Although.not an agency, Petaluma Basin Zone 2A consists of the Petaluma River watershed within
Sonoma County Supervisori'al District #2 that drains irnto the Petaluma River, as shown in Figure 3.
It operatesunder the authority of' Sonoma County Water Agency and iis a means of financing the
construction and maintenance of flood protection works within this watershed.
The City is currently working with these agencies and `various community,groups to support creek
clean -up programs and promote opportunities to engage the publican implementing the SWMP.
Since these agencies share in bath the benefits of the City's stormwater program and the
responsibility for stormwater drainage and flooding components in the - larger watershed, they
could be coinsidered as potential sources or partners for future funding of the maintenance and
construction of needed SWP capital improvements, as discussed,in Section 3.
20 Appendix G, Marsh /Bay Habitat?in the Petaluma River Watershed, Southern Sonoma County Resource Conservation District, Petaluma River
Watershed Enhancement Plan; Aprit'1998; p:, 1.
21 USACE, Threatened, Endangered, and.Sensitive,Species Protection and Management System,
(hftp://el.erdc.usace.ar,my.mil/tessp/project.cfm?fd=435)
?? Source: Sonoma County Water,Agency website (f ftp:/Avww.scwa.ca.gov/flood-protection-zones/).
23 City of Petaluma, Annual'Report, General Permit for Discharger of Storm Water from Small Municipal Separate Storm Sewer Systems (MS4's),
September 2009, p.T
076 50338 -028 3
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2.3 Current 'Program Funding M "echanisms
2. 3.1 urren t Funding Sources
The City's current °SWP funding consists of two parts: (1)' annual
operating and maintenance, (O&M) costs, and (2) capital
improvement costs. O &M activities are by definition intended
to operate and. maintain existing facilities whereas capital costs
include design and ;construction of new or expansion of existing'
facilities. Capital costs alsol typically include renewal or
replacement of major facilities: Currently the City provides
approximately $ 820, 000 per year for the stormwater program, which represents approximately 2%
of the monthly sewer, bills paid by current sewer system customers. These funds are used almost
exclusively for O &M costs.
In the past, the City has received. assistance: in °funding SWP capital improvements from Sonoma
County Water Agency Zone 2A, and the RCD. The City has also received approximately $3"
million in grant funding from°the State Department of Water Resources (DWR) -for land
acquisition, flood terrace construction, and stream habitat restoration. The grants, included
$850,000 in 2010 for'land acquisition of floodway and floodplain designated properties in the
Denman Reach of the Petaluma River .24 However, stormwater capital: improvement are not
currently included'in the City's sewer rates or wastewater utility financial plans. This lack of a
systematic, long term sourceof capital funding severely limits the improvements the City can
make and leaves most planned or desired improvements unfunded until a grant or other
m
assistance is obtained fro an outside source.
The City's current sewer rate structure1s based on cost -of- service principles intended to equitably
allocate wastewater utility costs, including annual stormwater program costs, to and within
customer classes. The. City prepared a full cost -of- service analysis of'sewer rates in the fall of 2010,
which included the storm water component. The new..five -year, rate- structure recommended in
that study is now being considered through the public review process, including the Prop 218
Balloting, process. The recornmended increase of 9% for Year Yof'the Draft Rate Study was
implemented, effective January 1, 2011, and was 4% lower than the previously,adopted' 13% rate
increase.
Sewer rates consist of fixed monthly charges based on customer class and /or meter size, plus
volumetric'and strength charges. Volumetric charges are based on average winter consumption for
single - family residential customers and monthly water usage for other customers. Strength charges
are assessed to some large industrial customers' whose wastewater is sampled and tested; these
test results serve as the basis for their "strength" charges.
Fixed monthly charges are intended to reflect costs that typically do not vary with the amount of
wastewater handled by the City's treatment facilities, such as debt service, personnel, and
24 California Regional Water Quality Control Board, Executive Officer's Report, October 6, 2010, PA.
- 07685 -? 50338 .c18
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administrative and overhead costs. In contrast, volumetric and strength..charges are intended to
reflect variable costs; which typically change with the amount and strength of wastewater and /or
number of customers in the, system, such as pumping costs and chemicals.. Based on these
concepts,.SWP costs could be included as part of both fixed and variable charges (e.g., some costs
could be attributed to'stormwater= related I /'1 pumping costs)'.
The residential rates-that have been.implemented, are shown in Table 1.
Sewer customer classes:include single - and multi- familyresidential, non- residential with low -,
medium - and high strength wastewater, and larger metered industrial customers., Single- family
residential customers pay,, a'fixed monthly service charge of $17.22, plus a $7.45; per hundred cubic
feet (hcf), variable charge based on the average - winter water consumption. Typical ,single- family
winter water consumption is:.6 hcf /month, resulting in,a. typical monthly bill of $61.94.
The City's utility rate. studies undertaken since the passage of Prop 218 have included the
stormwater component in the wastewater rates; ,public input.has been solicited through the Prop
-218 noticing, public "hearing, and adoption process. The methodology and justification for using
the City's sewer rates to fund stormwater program costs are discussed in Section 3.
25 Proposed: Wastewater Rates (2011), Water and Wastewater, Financial Plan and Rate Study;,;Exhibit IV-7, page 54, The Reed Group, 10- 27 -10.
,. h 07685 '503 - J[8
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Although briefly mentioned in previous sections, the City's SWP deficiencies and planned capital
improvements are discussed in more detail below, and underline the need for additional revenues
for both one -time capital'projects well as ongoing maintenance activities.
3.1 System De ficiencies
Up until 1987, the SCWA provided maintenance of stream and creek channels within their
jurisdictional authority by reducing:overgrown vegetation in order to maintain runoff capacities.
Unfortunately, Sonoma County Water Agency discontinued this practice at. that time at the request
of the California Department =of Fish and Game. Maintenance of "individual creek segments is now
conducted only in response to a request or emergency call. Thus, the,hydraulic capacities of these
facilities have decreased as vegetation and debris.continue to accumulate within channels and
culverts, thereby potential flooding problems. Additionally, obtaining the necessary
regulatory permits for channel. work has added time and expense to these activities thereby
reducing the frequency and amount of maintenance possible.
As a result, the primary deficiency in the City's ;stormwater system is the declining hydraulic
carrying capacity of the,SWP's creek channels to adequately handle the runoff from large storm
events: The primary areas currently,experiencing these types ,of .flooding problems include:
0 The Corona Reach (Lynch Creek`- confluence upstream to Corona Road).
Denman Reach — Corona Road to Rainsville
Road, which includes unincorporated areas, in the
County.
is Areas below the Willow Brook Creek confluence
with the Petaluma River.
Willow Brook (downstream. of Ely Road).
Areas adjacent 'tothe Marin and Liberty Creek
confluences .(located in unincorporated County).
Kelly Creek culvert at Sunnyslope Avenue.
In addition to the open channel hydraulic
deficiencies noted above, many of the City's west-
side drainage channels pipes, and similar facilities
are past their useful -lives and are in need of repair.
Finally, the City's two pumps at the Wilson Street`Pump Station have exceeded their useful life
and should be replaced to maintain hydraulic capacity and increase system reliability.
07635 5 G::i 3 8 -02x3 7
Example of vegetation overgrowth in a
creek channel.
A m , s
•: .. i i a
3.2.1 Drainage Channels
Maintaining and /or improving the capacity of the numerous creek channels, collection basins,
pipes, culverts, bridges, and open channels is and: will..continue °to.be a major focus for the City's
stormwater system. T lie City's River Access and Enhancement Plan and the General Plan 2025
outline keyimprovements needed to maximize the hydraulic carrying capacity of the stream and
creek channels, including creating flood terraces and low-'flow channels, habitat restoration, and
managing and controlling stream bank vegetation. These activities, _and improvements reduce the
buildup of channel debris, improve channel flows, and provide ongoing benefits to the City's
sewer customers by further reducing I/1 flows currently processed at the Ellis Creek WRF.
The Sonoma County General Plan,, summarized the City's flood related needs as follows:
"The City has identified: the need to preserve andj enhance the natural flood detention
capacity, particularly along the headwaters of the Petaluma River outside the City limits, as
a key element of reducing flood'hazards in the City. "z6
Regional t nt o Facilky
There.is a regional detention facility sited at the confluence..of Willow Brook. and Lichau Creeks,
which is defined in the Petaluma River Watershed Master.Drainage Plan. Increased rainfall and
development in the Penngrove areahas resulted in increased runoff flows, which have increased
flood conditions downstream of Penngrove. The historic capacities of the urban creek corridors
and piped systems within ,Petaluma are not to handle the increased flows now entering
the City at the two major creek confluenees°withIhe Petaluma River: Funding for the regional
detention facility is not yeHn place.
The City is in the final stages oP the $40 million Payran Flood Control Project'in partnership, with
the U.S. Army Corps of,Engineers.' Pending the City obtaining funding for this final phase,; the
project anticipates a'two -year completion timeframe. Once completed, this improvement' will
effectively eliminate the repetitive loss zone within the:Payran reach
Major development proposals such as Sonoma Mountain Village In Rohnert Park and Redwood
Shopping Center at the intersection of Old Redwood Highwayand North McDowell Boulevard
have incorporated smaller. detention facilities into their master plans to address project specific
impacts to downstream capacities. Project and site - specific mitigations help reduce off -site
stormwater flows that would otherwise add to the requirements of downstream system -wide
improvements.
Sonoma County, General Plan — Public Safety Element, September 23, 2008, P. PS -8.
27 City of Petaluma Floodplain Management Plan, October 4, 2010, p, 4.
18 0685 - 1.`50338- 0 28
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The City's stormwater master plans have also recognized the need for two types of activities: (1)
providing vegetation maintenance and /or habitat restoration to improve; channel carrying capacity,
and (2) constructing flood terraces in the most critically,. _impacted, creek channels. In 2005, the City
completed the first phase of a, stream;channel improvement project in the Denman Reach that both
removed non - native vegetation above the low -flow channel' and created a flood terracing area of
approximately 1,400 linear feet of river frontage. However, City staff, estimate there are
approximately 20 miles of additional stream channel that must be maintained and /or may need
vegetation control.
To illustrate the longer -range needs, if the City was
able to restore channel. carrying capacity of aft
average of 5,000 to 6,000'linear feet per year, it
would take approximately 20 years to make
improvements to the open drain age „channel's
within the City. Given the cost-oOlthe required
restoration work, and accompanying:mtigation
measures,,it is infeasible to! achieve this without
significant additional funding sources.
Based on.the City'sexisting Sform Water Master
Plan, Petaluma Watershed Er>liancemera.1 an, and
Sonoma County Water Agency's -2003 Petaluma
River Watershed' Master Drainage Plan, the City
has identified at least $1.5 million of :immediately
needed improvements, to maintain hydraulic "capacities in the system, including:
Pump Station Improvements (specifically replacing the pumps at Wilson Avenue Pump
Station)
Repair other stormwater, pump stations (including wet-well maintenance and pump repair)
Repair of culverts in various creek channels (e.g., the Kelly Creek culverts)
These are "planned" in the sense that the.City and other agencies.recognize the need, for, these,
improvements in order to maintain at least the system's current stormwater handling capacities.,
These improvements. are routinely evaluated within a system that ensures they, are "amortized over
their useful: life. 'However, the City is currently only able to fund improvements on an as- funding-
is- available basis rather than an as- needed - basis. In light of current funding deficiencies, these
improvements will require significant additional funding sources.
2e City of Petaluma, Remleh Scherzinger; April21, 2011
2 That is, 22 miles is 1.16;000 linear feet; divided by 20 years equals 5,800: linear feet per-year.
0.7685 -1 5 0338 ,0 "2 8 i9
Denman reach stream terracing and
channel improvement project.
4. ;
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SEC TION - STORMWATER PROGRAM FUNDING EVAtUAT
"Funding Mechanisms" can:include a wide variety of revenue, sources` -to pay for capital
improvements and /or operating and maintenance costs.. Table 2 summarizes, some of the broader
funding mechanisms typically applied to stormwater programs, categorized by best management
practices- (BMPs).
Since this evaluation specifically addresses stormwater rates, this report focuses on stormwater=
ref
ated,.rafe- making principles (as opposed to wastewater rate principles). These principles include,,
(1),genetaFfate setting criteria (2) more specific cost -of- service rafe= setting - principles, and (3) Prop
218 requirements. These three categories are discussed below.
While local agency policies have an important role in establishing a stormwater rate methodology,,
several.broader rate - setting criteria are typically addressed, including:
Meeting Annual Revenue Requirements
30 Lindsey and Doll, Financing Retrofit Projects: The Role of Stormwater Utilities, from the proceedings ofthe,EPA National Conference on Retrofit
Opportunities for Water Resource Protection in Environments, Chicago, Illinois, Feb. 9 -12, 1998.
20 07685- 1 50338 2 8
tal�s titxtx 1'N tt�t Fun sa►�I lssri _ . '
4
Providing Revenue Stability
Adequately Funding Repair, Replacement and. Future Capital Improvement Costs
Establishing Rates that are Fair and Equitable and'Easy'for Customers; to Understand
Maintaining'the Financial Health of the Agency (including sufficient reserves, meeting debt
service coverage ratios, and observing appropriate financial management policies)
4..x:2 Industry Wide Ra te Fonda tals
The industry -wide fundamentals of rate setting methodologies are generally credited to James C.
Bonbright in the Principles of.Pubtic Utility 'Rates 3 but are also reflected in the Principles of Water
Rates, Fees, and Charges; 2 published bythe American Water Works Association (AWWA). This
AWWA publication is' considered by many to, be the most widely used standard for rate setting
today,. Both these documents outline pricing policies, theories, and economic: concepts along with
various criteria for selecting a,rate structure. A simplified list of the attributes that should ,be
considered in selecting a'sound rate structure includes:
Rates should be easy to understand from the customer's perspective
Rates should be easy to administer from the utility's perspective
Rates should promote the efficient allocation of the resource
Rates should be equitable and non - discriminating (i.e., cost based)
There should, be continuity in the rate making philosophy over time
Other utility policies should:be� considered (e:g., encouraging conservation, economic
development, etc.)
Rates should consider the customer's ability to pay
EM Rates should provide revenue stability from month to month and year to year
These principles define the, parameters within which rates. should be developed, but they also
suggest that there is sigrnifieant latitude for local agencies to adopt a variety of rate, structures.
The process of setting rates and developing a sound rate ,structure should strive to incorporate the
industry standard cost- of- service.principles included in the Bonbright and AWWA publications
noted above. However, many rate economists and regulatory agencies believe that cost -based
attributes should be of primary importance in guiding utilities on rate structure and rate policy
31 James C: Bonbright; Albert L. Danielsen and David. R. Kamerschen, Principles of Public Utility Rdtes, (Arlington, VA: Public Utilities Report, Inc.,
Second Edition, 1988), p. 383 -384.
32 American Water Works Association; Principles of Water Rates, Fees, and Charges, Manual of Water Supply Practices, Manual M1 (Fifth Edition,
2000).
r
07685 2
issues. This is because cost -based attributes address the fundamental cost allocation methodologies
that lie at the heart of equity and fairness in rates.
Cost of- service rate studies typically address both the
magnitude of funding and the rate structure:design. In other
words the arnount.of revenue collected (e �g., $10 million per
year) and the way in which the revenue is collected from the
customersare equally important.
A rational nexus between the charges paid Land the benefifs.received by rate payers is an over -
arching requirement of rate setting methodologies. To illustrate this point, assume that a rate
structure and /or the specific cost allocation methodology were, to. be challenged in court and
brought before a judge.'The explanation of the cost- allocation methodology should be sufficient to
persuade a judge that there is a "reasonable" nexus between the rates customers pay and the
benefits those, customers receive.
Therefore, while there is no single rate methodology or rate structure - mandated for stormwater
program funding the "most accurate" rate: methodology is not required in every case, and no
single rate structure should .be applied in every case.. This is true even- though another
methodology may be more equitable, more accurate in determining the °cost- causation attributes of
individual customers, or maybe more appropriate in some cases. But what is ultimately required
is that the methodology demonstrates a reasonable relationship between benefits received and the
charges collected from stormwater ratepayers.
Under California law, Proposition 218 treats stormw, ater rates in the'same manner as water .and
sewer rates. It imposes a number: of additional requirements related to how stormwater rates are
developed, and adopted, including requirements for: (1) equity between customer classes, which is
typically determined through a .cost -of- service analysis and excludes subsidies of any•customers -at
the expense of other customers, and'(2) public noticing, a protest- ballot-process, and public
hearings in order to `adopt and dinplement the rates.
The first et of re uirements. is, ba
, q sically consistent with the cost -.of- service rate setting principles
discussed above The second set of requirements applies to the actual adoption process,. which
does.not,necessarily'impact the funding mechanism itself.
4.2 Alternative . tormwater Funding 'M'echanism's
HDR reviewed a wide range of funding mechanisms used by both stormwater and other types of
utilities responsible4or stormwater programs. The review included' agencies in California and
across the nation. It, indicated that. there is no single, universally accepted "best" funding
mechanism, although some.may be more. equitable than others or provide other advantages such
33 Called the "Right to Vote on Taxes Act," Proposition 218 adds articles XIIIC and XIIID to the'California Constitution.
..�........
u �:�
22 0 768 , 50338 -028
as being easy to administers simple=to understand,and /or
broadly accepted "in the community. For example, historical
methods that have been used to fund stormwater program
costs include:
Sewer Rates: Asa part of protecting and
groundwater quality, stormwater facilities prevent
overtaxing of,sewer capacities,` which can endanger these
resources. This is particularly true for combined sewer - stormwater systems.
• Water Rates As a function of providing sources of safe drinking water, including surface and
groundwater, water rates can be justified in funding stormwater programs when they protect,
enhance, and /or help recharge these water supplies.
• valid. lV ste .bates: Clearing of "trash" from stormwater collection basins keeps both trash and
related pollutants out of the drainage system, thereby protecting water quality and preventing
flooding that may occur when debris clogs collection basins.
FZ Street Sweepitig'Cbarges: Although it is uncommon to fund stormwater program costs
entirely through street:: sweeping charges, debris and pollutants that accumulate in streets can
directly contribute to contamination of surface and groundwater when debris and /or
contaminants are carried by storm into stormwater basins and ultimately into surface
waters and /or,groundwater recharge areas. Cleaning streets and stormwater collection basins
reduces local flooding, and these 'types of stormwater program functions have been funded
through street sweeping charges.,
Mori water. Utility Charges: Historically, the number.of stormwater utilities has been very
limited. Currently there are roughly 1,000 stormwater utilities operating in the U.S. However,
they are becoming more common as municipalities are faced with constructing and operating
stormwater improvements to meet NPDES, Clean Water, and state /regional water quality
board requirements. Communities. with dedicated stormwater utilities typically develop
separate stormwater charges, which are most commonly based on °impervious surface area,
and mayinclude /runoff coefficients or related factors intended to quantify contributions
of individual parcels to storm- related runoff.
4,2�2; Di of Standards for Funding Stomwater Programs
This section reviews industry standards and various fundingmechanisms.and methodologies used
by other municipal utilities to fund stormwater costs.
Two industry surveys of'stormwater'funding mechanisms are summarized in the following
subsections, followed.by several case studies of stormwater rates from other cities. These
summaries indicate that a wide variety of stormwater rate structures are used in California and the
U.S., and that no particular methodology can guarantee legal defensibility;`however, some
methodologies may be lookedupon more favorably by the courts. Regardless of the methodology
used, there still.must be a reasonable relationship, or nexus, between the costs paid by the
beneficiaries and the level of benefits they receive.
67685- 5()338 -028 23
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x,2.2. ,s " "' West6r r Universitv S arv ey
A 2010 stormwater utility'surve_y, by Western Kentucky University (WKU) confirmed a total of
1,112 existing stormwater utilities in the US., but, estimates there maybe asrmany as 1,500. The
average population served by the confirmed stormwater utilities is'82,000. This survey focused on
legal challenges to stormwater rates,,:and found a tonal of 29 cases. Of those 29 cases, 21 were
upheld, five cases resulted, in rate structures that were struck down, and.three cases are still
pending. The 21' cases upheld - included 14 with stormwater rates based on,equivalent residential
units (ERU's). The WKU survey was somewhat` inconclusiveregarding the reasons for the striking
down of rate structures in the five cases that were struck down;:two were based on E RU's, one
used parcel size, one used impervious surface area, and the basis for one was unknown.
Overall, 572 communities used ERU'.s for their rates; with average and median ERU`s of 3,000 and
2,700 square feet, respectively. The average single- family monthly fees were $4..12, with a median
fee of'$3.50.
The author of the survey also'offered two key opinions about stormwater rates:
Best Way to Determine Storm water bees: The community's legitimate stormwater needs
should be identified and ,the fees,set accordingly; ;if the stormwater' needs are flooding and
water quality, then legitimate uses of those funds should include design and construction of
water"quality and flood- prevention capital improvements stormwater facilities maintenance,
staff salaries, education and outreach, and administrative costs.
ERU!s as the, Basis for`Fees: Equivalent residential units are the most direct method of
calculating stormwater fees, and it is important that an accurate estimate: of an ERU is
developed: If'the ERU (e.g :, in square feet of imperious area) is °under- estimated, single- family
residential customers will pay less than their fair share; if the ERU is over estimated, non -
residential customers wilt pay'less than their fair share.
A modified ERU system based on "tiers "'of impervious surface area is also commonly used. This
approach is simpler because it c. ategorizes customers into group's (ortiers) covering ranges of
impervious square footage. This avoidsmaking square calculations for each parcel, and
individualfees;for every customer.
. 2 veaIch Surv
Black.& Veatch conducts an annual survey of stormwater funding. mechanisms that, in 2009,
received °responses back from 70'utilities,covering 20 states 36 Some of the key findings,from this
survey are:
The basis for user fees was 55 %o impervious surface area, 7% gross area with a development
intensity factor,,3% gross area with-a runoff factor, 29% gross area with both a development
factor and runoff factor, and 6% other.
34 Western Kentucky U niversity,Stormwater UtilitySurvey.2010, C. Warren Campbell.
35 This study actually iridicated the. basis,forrates of two cases were unknown, but one of the unknowns. was the City of Salinas which,. as discussed
below, confirms the City used an iimerviousssurface °area methodology:
36, 2010 Stormwater Utility Survey Sponsored and administered by B &V Management Consulting.
e. k
2 4 07685- ;50338 028
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The stormwater contaminants of greatest concern,are; sediments (88 %), nutrients (71 %),
pesticides (52, %), oil and grease. (52 %), heavy metals (45 %), and other (32 %).
93% of respondents said the stormwater fees were the same for all service areas or watersheds,
while 7% were not.
80% of respondents collected most (90 % or more) of their revenue from stormwater user fees,
while 20 % have multiple sources.
50% of the respondents were separate: stormwater utilities; 30% were combined with a public
works department, 11% were combined with a wastewater utility, and 9 % were other
structures.
® 81% of respondents served a city rather than county or region.
Utilities using an ERU basis.had an•average ERU of 7,253 square feet, while utilities using.
impervious surface area'had a average ERU of 2,453 square feet.
:
75 % of respondents indicate 4stormwater fees are included in water or other utility bills, 21%
are included with property tax bills, 7% send special bills, and 3% use other means.
4.2.3 Case Studies,of5tormwater
Several case studies of stormwater are discussed below.
r Cit o f Santa Rosa C lU s;
Santa Rosa's and'Petaluma's annual stormwater budgets are roughly equivalent when compared
on a per population basis. That is, Santa Rosa's 20107populati'on3 2.9 times larger than
j'' Petaluma's, so Petaluma's annual stormwater, budget of $820,000:•tines this population factor of 2.9
is $2.3 million (close to Santa Rosa's budget). -A separate stormwater utility serving Petaluma
r properties might be close to Santa Rosa's current fees of$27/household at current funding levels.
37. Respondents' were allowed to select multiple contaminants,..so percentages total more than 100 %.
38 'City of Santa Rosa, 'Storm' Water' and Creeks, Summer 2008', www. srcity.org /stormwaterandcreeks. Also, phone conversation with the Santa
Rosa Stormwater Utility teve Bratl Y , 3-14 -11
Y� )
39 According'to the 2010 "Census, Santa Rosa's population is 167,815, which is approximately 2.9 times Petaluma's population of 57,941. Source:
California Department of Finance,.De'mographic Research Unit.
. ,_
076.85 - ?50338 -02.8 25
,4.2.3,2
City bf Val i J o, 'California
.� " .f..
The City had been using a. flat rate stormwater fee of $1.97 /month for every sewer account,
regardless of customer class or property characteristics. While this provided a very simple charge,
many impervious areas such'as parking lotswifhbut a sewer account were not charged a fee.
When the City needed to increase fees, they felt they had to make a compelling case to the public
that the fees were equitable in order to passthe Prop 218 ballot process. However, the. City's
existing "flat "rates" were` determined" to be inequitable since they did not account for varying
combinations of pollutant and runoffloads. The City's primary message to property owners was
twofold: (1) that new rates reflect both runoff and pollutant loads tied to impervious surface area
and are equitable and, 2
q the stormwater system protects property from flooding and protects
O t
waterways from pollution. Once all parcels. (not just sewer custorriers)`were included in the rate
analysis, single4amily residential customers' bills actually went. down by 10 % due to the non-
residential properties added to the mix
ity of Salinds', California
The City, hich has se stormwater y p and sewer collection systems, was sued by the Howard
,
Jarvis Taxpayers,Association,over whether the fees were subject to Prop 218 requirements. The
City had applied these'rates to "users of the stormwater drainage system and to every developed
parcel, "with.fees calculated based on.:irnpervious surface area. Undeveloped parcels were not
subject" to the rates. The 2002. decison held that the fees were subject to, Prop 21'8 but did not find
,i „
fault with the impervious surface area method used to calculate the fees.
The County uses impervious surface area and ERU's to determine: stormwater fees and has a flat
rate of $5.84 /month for single - family homes, with - condos set at -60% of the single- family rate and
non - residential rates based on their square' footage of 'impervious surface area.
4, 2, 3 5' Bakersffiald, California
In June. of 2010, the City adopted a flat -rate combined sewer/ stormwater rate structure. Single -
family rates were $200 /year ,($16.67/mo,). The City's rate ordinance riot "ed that 5.5% of the rates are
a ortioned to sto
pp rm sewer °use, maintenance, replacement and improvements. 42
4; 2, 3.6 City of Portland, Grc pn
Portland's Environmental Services Department provides,residents. , and businesses with wastewater
and stormwater collection and treatment, sewer • installation and maintenance,, drainage services,
and watershed restoration.; Since f977 Portland has charged a.separate stormwater utility fee to
help pay for stormwater' management costs.
Kenneth S ra and Grant Hoa
ao p y g, "Stormwater'Program Funding in California," APWA Reporter, Dec. 20031Jan.;2004, pp 25-27.
4 Westlaw, 2002 Daily Journal D.A:R. 6161, Howard, Taxpayers Association, et. at., Plaintiffs and Appellants, v. City of Salinas, et. al.,
Defendants and Respondents. Note.'this : case was prior to the,Bighom- Desert View Water Agency decision in July of 2006, which further settled
the application of Prop 218!to utility rates.
42 City of Bakersfield, California, "A Resolution Establishing Sewer and Storm Sewer Service User Charges ", adopted June 9, 2010.
h
In 2000, the City:re- evaluated stormwater rate alternatives and determined that 70% of the
stormwater management costs should be allocated to public transportation rights-of-way (streets
and roads), 23 % to property runoff, and 7% to environmental protection and restoration. One of
the key principles and assumptions in their evaluation was that:all properties and ratepayers are
responsible for transportation and environmental components of the stormwater utility.
In 2006 City Council established a reward system for ratepayers who keep stormwater from
leaving their property „offering residential ratepayers up to a 30- percent discount for managing
runoff from their roof areas. Commercial customers get discounts for managing runoff from both
roof and paved areas. Credits are also offered 'for having a small impervious footprint (less than
1,000 square feet), creating or maintaining tree coverage, disconnecting downspouts, installing rain
gardens or 'drywells, and other low`impact'development BMPs..
The City's current monthly stormwater rate is $8.25 per 1,000 square feet of impervious surface
area, which are .divided into on -site costs (35 %) and off -site costs (65 %). Ratepayers who manage
stormwater on their property can receive up to a 100% discount of their on-site charge.
. 2, J. p City o f ,: t; .$ saving; e n
All parcels in the City are subject to a stormwater utility charge, regardless of whether a
stormwater system.from the parcel is physically connected to the. City's, public., drainage system.
The City states that drainage from most properties enters or impacts the City stormwater system in
some used, for many purposes that benefit all City residents and property
owners. In, 002 the City budget allocated stormwater.fees'for capital improvements and debt
service (33.3 %),,operations and maintenance (31:5 %), engineering (17.2N, shop maintenance
(10.6 %), and miscellaneous overhead (7:3 6 /.). 44
4,2,3.8 City of t ch ru_ Ontario, C ,4 , cfa
In 2010, the City of Kitchener implemented ,a "tiered flat fee” stormwater rate structure based on
impervious surface area. The key characteristic of this rate structure is that it shifted the overall
stormwater program costs from residential to non - residential properties, including both taxable
and non - taxable' entities.
As these examples illustrate, various cities and stormwater utilities use a wide variety of4unding
mechanisms to pay for stormwater system. costs. The next section discusses potential funding:
alternatives the ;City could consider as. well as options for how new funding sources could be
collected from beneficiaries.
°y
When an agency is considering, developing either a new funding mechanism and /or a separate
utility, the technical; factors.and,rate methodologies'are secondary to several other key
considerations, including.
Is the funding method politically acceptable?
Is it equitable in the public's eyes (the benefits accruing to those paying the fees)?
Is it feasible to implement? ..
Is it reasonably easy to .administer?
Is it legally defensible?
Can it generate enough revenue: to sufficiently fund the capital improvement and O &M costs
as- determined by the responsible agency and decision- makers?
Willit provide. a dedicated source of revenue or will other agencies' and services be competing
for the same funds ?
4. 2, 1 A Separate —Storrowanbr Utility
More.and more cities_ across the U.S., are creating 'a separate stormwater utility as a means of better
managing their stormwater10 &,M and costs. Escalating regulatory
pressures-and costs such as those related t
' p , o NPDES permit - requirements; have been a primary
factor behind this'trend.
g p stormwate r utility would require significant political will,,public support,
and coop'.eration;from adjacent agencies. If this.is the case; then the City should consider this
approach. However, if the City is only going to continue providing the current level of SWP
services,, then continuing to fund stormwater costs through sewer rates is a more reasonable and
cost - effective approach.
. 'I - . i i1
2. 4 p 2 Impervious r d: Area-Baseri Fee
fi
As noted above, HDRbe'lieves tl at,the City's current use of sewer'rates to.fund the SWP costs is
reasonable and acceptable. The reasons why changing the rate structure may not necessarily be
advisable-include implementation costs, significant commitment ofstaff time, etc., and raise a
qu estion e eigh the costs. However, in light of
the current unfunded a d e e
exp-d fut re increases in SWP costs, the City should move ahead
with plans to develop an impervioussurface area based rate structure. City staff concurs that the
SWP has reached the point where this is imperative due to the need to fund capital improvement
costs.
A new impervious surface area based rate structure could
include various components; such as (1) measured
impervious surface area (ISA) by parcel, (2) ISA plus slope
coefficients, (3) ISA plus pollut on,coefficients, (4) "tiered'
residential and /or non - residential' rates that; provide xanges
of ISA tied to rates, or (5) some combination of the above.
The fundingand assistance provided by other agencies within : the'same watershed reflects the
beneficial ,relationships between various flood control, water quality,, and habitat improvements,,
and the long4erml interest's of�those:other agencies. In the' City's' case, other agencies (notably
Sonoma CountyWat&Agency, 7one,2A, and the -RCD) already, provide funding and assistance in
the form of limited storm water capital and - occasional channel maintenance projects rather than
direct funding to the City or its sewer utility. However, given the planned capital projects and
O &M activities that are currently under - funded, other agencies, , as well.as the unincorporated
areas in the watershed benefiting from the City's efforts, may be sources of, or partners with which
to seek additional funding on a more regionally balanced and equitable sharing of costs.
As noted in the industry surveys above, the, vast majority (93 %) of beneficiaries within watershed
were all charged the same stormwater fees. Currently, although the City receives limited funding
4 Other factors such as slope.and pollutant factors may also be considered.
..._.
0 1,685 1 50 338-02 29
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from other local agencies, , t:rece ivies very limited direct funding from unincorporated properties
that benefit from the City's SWP unless they are sewer.customers of the City. In light of the
continued increased flows from unincorporated areas `into the City's Swl?,, any new funding
mechanism should carefully evaluate funding from these properties.
n 2. 4,4 A 4,. 3 9` i e.: d „' e E a �*.. c)J 1 e c t h,) n X
How fees are collected from customers and /or properties is a separate discussion from the basis for
the funding mechanism. However, there three fairly straight- forward options: (1) inclusion in
other utility bills.(e.g., sewer I rates; the City's current method), (2) direct billing through a separate
'I stormwater utility, and '(3) Collection as a part of'county property taxes.
4.,3 -Analysis of (E$.enefiria;ries and Equity
Over the years SWP costs have increased as protection of surface and groundwater supplies has
been given greater priority, particularly in the form of specificrequirements .embodied in NPDES
permits. As a-consequence of this,' the importance of SWP funding mechanisms and additional
funding sources:also increases.
3: Basis for Funding.Stormwater Program with Sew .. Fund:
One industryexpert summarized how stormwater systems have been typically funded as follows:
"Most jurisdictions historically have paid for investments in stormwater infrastructure with
revenues from property taxes and other general revenues..Many, if not most jurisdictions,
°now rely;on a variety "of s.ourees ''to f nance comprehensive stormwater programs. One key
observation from [the list qf fundin sources] is that' the sources of revenues most important
for retrofit programs are property taxes and stormwater user charges "49
This historical perspective should be considered when evaluating the City's stormwater funding
mechanism because:it shows the Pit Y 's,,current method is consstent`with the practices of many
,
other municipal ufilities with. similar,responsibilities for
stormwater programs. Ultimately, the key factor in
evaluating whether it is appropriate, for the City to fund its
current storrnwa - ter program costs through sewer rates is
the�relationship�•between SWP costs and the benefits
.received by sewer customers. If the City were to
implement a b
Aar grid more %comprehensive funding
mechanism, such as an impervious surface area -based fee, properties,that contribute runoff and
receive benefits from the stormwater'system, yet are not sewer customers, would more equitably
contribute their fair share of SWP costs.
The SWP costs funded by sewer rates currently focus on annual maintenance activities and
account for approximately 2% of the wastewater utility's total annual budget. Historically, SWP-
it 4 8 The exception is funding from Zone 2A parcel tax - funded projects within Petaluma.
. :49 "Lindsey -and Doll, Finahcing Retrofit'ProjectsThe Role ofStormwater Utilities, fromtne,proceed ings of the EPA National Conference on Retrofit
Opportunities for Water Resource Protection in Environments, Chicago, Illinois, Feb. 9- 12,199$..
30 07685 50"338 C-128
Ct tat l�s kuua lornlwwatwr�] t "tt�daa� w lit tt t .
Iii i t i
'' � ,, ,,, -,"a_ �n1�`N 'e �aws 3�«• Rsn �, c«�+; - I y'x
1 related capital improvements have included improvements to the wastewater, collection system to
either eliminate or reduce, combined sewer /peak wet weather flows associated with stormwater
related 1/1 (e.g. the PIPS improvement in 2001). Improvements that:reduce the frequency or
severity of SSOs, and the associated health and safety risks, have been undertaken atkey system
facilities, such.;as pump stations:
Until such time when, and i'f, - the sanitary sewer collection system, is, improved to significantly
reduce I /I; the sewer collection °system must accommodate the'peak storm event flows. Several
adjacent agencies or funding.entities (e:g., Sonoma County Water Agency, Zone 2A and RCD) have
also. funded creek channel im' provernents, watershed planning,41id'ies mapping, and
improvements in both the City's service area and the larger Petaluma Watershed.
Although we have stated that continuing to fund the City's SWP costs, through ,sewer rates is a
reasonable and, cost- effective =,approach, in light of the backlog of capital improvements and
deferred O &M activities the' City,should consider other funding options and /or funding
mechanisms in the future.
4.4 Conclusions
The previous. sections have summarized the City's SWP, its facilities, planned future
improvements, the basis for evaluating funding mechanisms, and alternatives to the City's current
use of sewer rates to fund the SWP. However, the' primary question this, evaluation addresses is
whether. the City's currenf'method is appropriate and reasonable, and. what other alternatives the
City might consider. HDR's conclusions regarding these issues are outlined below.
HDR believes the City's current fu'ndin :of
S
g WP costs through sewer rates is appropriate and
meets the requirements of both cost of service principles and .Prop 218. The primary reasons for
this conclusion are:
• Stor nwater Facilities 11 MeetkPrin.i.ary Sewer System Objectives: The City's SWP directly
d
supports the key objectives of City's wastewater collection and `treatment system, including
p ge e qu ality wa ter and groundwater. Additionally, sewer rates, including
the SWP fungi g m
'ro component, have been subjected to Prop 218- related requirements and
approved through,a', protest ballot, and public hearing process several times since this law was
enacted in1''995.,
• Storinwater Facilities Provide ;Flo €ad Control and Protect Sewer 'System Customers: The
Cit SWP SS �� s , I /I,flows, and
P d the severit y of flooding due to peak storm events.
There is a high correlati p receiving between the this benefit and the City's sewer
customers.
Storrnwate:r Facilities Help Minimize Server Bills: Apart from the City's SWP, the Ellis Creek
WRF would have been designed to handle a larger 1 /I= related peak capacity. Therefore, the
SWP is directly responsible for reducing long -term capital aiid_ O&M costs at the WRF.
M Practicality and Ease of r'1diuinistrat.ion Unless the City commits to more adequate long -term
funding for the SWP, continuing to -fund SWP costs at current levels through sewer rates is a
practical and�.:easy =to- manage approach.
076 50338 -028 3
�u
4.4.2 Other Fundin Options for SWP Capita
and O&M Costs
Although the City's current funding .mechanism by sewer
ratepayers is appropriate and defensible;'the City could
move towards an impervious surface area based'rate
structure in order to adequately fund, and allocate
significant capital improvement needs and deferred O &M
activities. The following are related' actions the City
should consider:
IM Creating a Separate Start iwatir Utility: Establishing a separate stormwater utility covering a
broader service area than just the City's sewer service area; this could also take the form of an
assessment district, joint powers authority, or similar entity. Further detailed evaluations of the
relative merits of a storinwate'r utility versus an assessment district would be needed before the
City could pursue either of these- optionsso
Establishing Impervious Surface Area -Base .Fees: A rate structure based on impervious
surface area (or a. similar ERU -based system) could include "runoff and/or pollution coefficients
to more equitably allocate: costs in proportion to cost- causation factors. These types of fees
could be added as a separate fee on the�sewe.r bill, or- through a new stormwater utility.
However, this can be a complicated, time- consuming; and costly.endeavor, so the City would
need to believe there are significant' advantages, and be willing to make a serious commitment
to this approach before pursuing. this option. We would expect the City to only °undertake this
effort if: (1,) the Cityis will to significantly broaden its stormwater management- functions
(e.g„ undertake extensive` capital improvements',and an enlarged service area), and (2) it is
politically viable to implement significantly, higher funding levels for SWP O &M and capital
improvements.
IN Developing. Additional Funding with Other.Ag,encies: The Sonoma County Water Agency
and RCD already fund some SWP O &M and capital costs,'and share in the watershed -wide
benefits provided by the City's SWP. Additional cost- sharing and partnering with these
agencies could be in the form. of capital improvements funded. and/or performed by these
performance of'O &M activities, annual;contributions t
agencies, � ' o the City's SWP O &Ivl costs,
or a combination of these approaches. Other options „might include_ re- establishing the
Petaluma' Watershed Zone 2A benefit assessment and'joint applications for grant fun, ding
sources.
Develop.i g l�nip.1'enientation flans: EDR,also recommends thatIhe City conduct an
'
implementation,study to determine more detailed plans for establishing a separate stormwater
utility, selecting a;specific rate structure, and developing related plans.forzchieving these
recommendations.
I 50 Evaluating these; differences is beyond the scope of this study.