United States
Environmental Protection
Agency
CASE STUDY
City of Folsom Collection System Asset
Management Program
Overview
With increasing pressure to meet state and federal regulatory requirements, eliminate sanitary
sewer overflows (SSO's), and prevent discharges to waters of the United States, municipalities
have a growing obligation to manage their aging infrastructure with limited budget and
resources. Asset management planning is an essential tool in maintaining levels of service for
water and wastewater systems.
In 2006, the California State Water Resources Control Board adopted a Statewide General Waste
Discharge Requirements for Sanitary Sewer Systems (General Permit), which requires
municipalities to develop and implement Sewer System Management Plans (SSMP's) to
facilitate proper funding and management of sewer systems. In order to anticipate and justify
current and projected costs of complying with federal, state and local regulations, the City of
Folsom (City) has elected to develop an asset management program as a component of its SSMP.
Background
The City operates a satellite sanitary sewer system made
up of approximately 358 miles of sanitary sewer pipe
(main lines, force mains, and laterals), ranging in size
from 2 to 33 inches in diameter and pumped throughout
the system by 15 pump stations. The collection system
discharges to the Sacramento Regional County
Sanitation District's regional wastewater treatment
plant.
The City experienced a major spill from its collection
system to surface water in 2000, prompting the Central
Valley Regional Water Quality Control Board (Central
-------
Valley Water Board) to issue a National Pollutant Discharge Elimination System (NPDES)
permit for the collection system in 2002. The City obtained coverage under the General Permit in
2007 and the Central Valley Water Board rescinded the 2002 NPDES permit thereafter.
As required by the General Permit, the City adopted the SSMP in August 2009, and revised it in
August 2014. The SSMP establishes specific goals to provide uninterrupted service, minimize
the risk of preventable SSO's, mitigate unforseen SSO's, ensure adequate sewer capacity, sustain
the aging sewer infrastructures by implementing an asset management program to extend asset
lifecycle, and ensure adequate funding support and resources to sustain long-term asset
management. The City's asset management program is critical to achieving the stated goals of
the SSMP. The City's asset management program integrates operation and maintenance, capital
improvement projects, condition assessments, funding, and risk and service levels to achieve
these goals.
Asset Inventory and Condition Assessment
The City utilizes a geographic information system (GIS) to display location and some asset
information for the collection system, including pipe locations, pipe sizes, manhole rim
elevations, pipe materials manhole depths, pump station locations, force main locations, and
sewer lateral locations. The City coordinated the GIS with their computerized maintenance
management system (CMMS) to avoid duplicate and conflicting databases. The City uses the
GIS to store static asset information (e.g., size, material, length, and slope), whereas the CMMS
stores dynamic operation and maintenance information.
The City thoroughly inspected and performed a condition assessment of the collection system
between 2002 and 2007. Based upon this condition assessment, the City developed an Operation
and Maintenance (O&M) Plan that defines a routine maintenance schedule and describes the
activities that the City performs to ensure that each component of the collection system is
inspected, cleaned, and repaired, as necessary, at least once every 5 years.
The O&M plan includes standard operation procedures (SOP's) for conducting closed-circuit
television (CCTV) inspections, manhole inspections, smoke testing, and sewer flushing/cleaning,
each of which includes a condition assessment component. Upon inspection, the City ranks the
inspected asset on a scale ranging from 0 (no defects) to 5 (emergency), and an action plan is
developed based on that ranking. Based on the ranking, a priority rating is assigned. Once the
affected asset has been assigned a priority, different methods to rehabilitate the asset and extend
its life are implemented (e.g., cleaning/flushing, manhole lining, cured-in-place pipe, etc.).
The City develops a System Evaluation and Capacity Assurance Plan (SECAP) approximately
every 3 to 4 years, which considers land use, inflow and infiltration, wastewater flow, hydraulic
modeling, and average dry weather and peak wet weather flows, to ensure adequate capacity and
identify areas with capacity issues to prevent overflows. The City first conducted the SECAP in
2003, and has updated the study three times, in 2006, 2008, and most recently in 2013. As a
result of the prior studies, the City identified problem areas and implemented several sewer
system improvement projects to improve the sewer system's reliability and reduce capacity
issues.
-------
Funding
Based on the results of the condition assessments and SECAP, the City develops a multi-year,
comprehensive Rehabilitation and Replacement (R&R) Program for the deficient systems. From
the R&R Program, the City develops a 5-year Capital Improvement Plan (CIP) for the necessary
projects in order to ensure adequate funding support and resources for sustaining long-term asset
management. Each year, this plan is approved and adopted by the City Council. The City's
annual wastewater budget is $6 million, of which $2 million is set aside for rehabilitation and
replacement projects. The City has spent $18 million over the last 10 years to rehabilitate and
replace pipelines, increase capacity, and upgrade pump stations, and is planning to spend an
additional $15 million for additional projects over the next 6 years.
Successes
The City has experienced a number of
benefits since implementing its asset
management program. The City has
reduced the number of sewer spill events
by 80% since 1998, and maintains an
average spill rate well below the regional
and state averages. A 2012 audit of the
program by the Central Valley Water
Board concluded that the collection
system was in good operating condition
and that the system has adequate capacity
for sewage flow, indicating a substantial
improvement in operations since the 2000 spill.
Category 1 & 2 SSO's per 100 miles per year
(01/01/2008 - 01/01/2013)
35
30
25
20
15
10
5
0
Central
Valley
¦State
¦Folsom
Mainlines
Laterals
Total
Source: City of Folsom Sewer Improvement Program, Informational
Presentation, January 2013
For More Information on the City of Folsom Environmental and Water Resources
Department:
City of Folsom
Environmental and Water Resources Department
50 Natoma Street
Folsom, CA 95630
Phone: (916) 355-7272
www.folsom.ca.us/depts/ewr
To access the plan, visit:
http://www.folsom.ca.us/depts/ewr/sewer system management plan (ssmp).asp
Publication Information:
Prepared by:
PG Environmental, LLC
570 Herndon Parkway, Suite 500
Herndon, VA 20170
On behalf of:
U.S. Environmental Protection Agency, Region 9
Water Division
75 Hawthorne Street
San Francisco, CA 94105
-------