Integrated Planning in Action
Columbia Wastewater and Stormwater Integrated
Management Plan
Columbia, Missouri
Hinkson Creek shows off its autumn colors.
Photo courtesy of City of Columbia.
Columbia is Missouri's fourth largest city, with a population of about 120,000.
It is located near the geographic center of the state and is well known for
its urban streams and lakes. Columbia manages its wastewater through a
separate sanitary sewer that the city owns and operates. It transports sewage
to the city's wastewater treatment facility1, which discharges to the Eagle Bluffs
Conservation Area—a large wetland that eventually drains into the Missouri
River. Columbia also operates a storm sewer system2 that is permitted jointly
with Boone County and the University of Missouri. The storm sewer system
discharges to Missouri River tributaries, including Hinkson Creek, which runs
through Columbia and features several trails and parks along its path.
During heavy storms, stormwater and groundwater enter Columbia's sanitary
sewer system through cracks and improper connections (i.e., infiltration and
inflow). This leads to sanitary sewer overflows (SSOs) that discharge sewage to
the city's waterways, and it causes sewage to back up into basements. In 2011,
the Missouri Department of Natural Resources (MDNR) initiated enforcement
negotiations with the city to address SSOs. Around the same time, MDNR
and U.S. Environmental Protection Agency (EPA) developed a total maximum
daily load (TMDL)for Hinkson Creek for biological impairment, an indication
that pollution is negatively affecting aquatic life in the water body. This is in
part due to stormwater discharges from
Columbia, the University of Missouri, and
Boone County. In 2013, the city invested
$64 million to expand and upgrade its
wastewater treatment facility to meet
new permit limits for ammonia. The city
anticipated that more nutrient, bacteria,
and dissolved oxygen limits would
be incorporated into the wastewater	% _	0.15
L(§kj city of
Sewer & Stormwater Utilities
EPA Region 7
120,000 population
Triple Bottom Line Weighted Criteria Developed
Through Community Outreach
"Wastewater treatment facilities" (WWTFs) is a
generic term for facilities that treat or manage
wastewater, including publicly owned treatment
Storm sewers and storm sewer systems can
also be referred to as municipal separate storm
sewer systems (MS4s). Stormwater discharge
permits can be referred to as MS4 permits.
Protect public
health and safety
| Social objectives
Improve quality
of life
sustainable service
for the future
Improve water
Comply with
| Economic objectives
Environmental objectives

treatment facility permit during future permit terms that
would cost another
$40 million.
Integrated Planning in Action
In 2017, Columbia and MDNR agreed that the city would
develop an integrated plan to prioritize wastewater
and stormwater improvements for consideration in
future regulatory decisions (graphic above). The city
hosted a two-day workshop with representatives from
various city departments, the University of Missouri,
Boone County, and the Boone County Regional Sewer
District to develop goals for the integrated plan and
strategies to meet those goals. The city kept the
public engaged throughout the planning process by
distributing fact sheets, developing a project website,
issuing press releases, posting updates on social
media, developing an online survey, and conducting
community workshops. Through these workshops, the
city developed community objectives to be used when
evaluating plan options (see box to right).
Columbia developed three funding levels, each with
a combination of sanitary sewer collection system,
wastewater treatment facility, and storm sewer system
projects that met or exceeded existing Clean Water Act
obligations. The funding levels represented incremental
amounts of infrastructure service, community
expectations, and anticipatory project commitments:
¦	Level 1: Projects to meet community expectations
and current Clean Water Act requirements.
¦	Level 2: All projects from Level 1 plus other
infrastructure commitments to meet known future
Clean Water Act requirements.
¦	Level 3: All projects from Level 2 plus additional
projects that meet all anticipated future
infrastructure needs and Clean Water Act
After outlining the three funding levels, city staff
calculated a total benefit score for each suite of
projects that represented the anticipated value they
would produce for the community. Community priorities
established throughout the outreach program formed
the basis for the scoring criteria and process. The city
then conducted a benefit-cost analysis for each suite of
Community Objectives for Columbia's Integrated
Planning Process
¦	Meet Clean Water Act requirements
¦	Protect important regional waterbodies
¦	Protect or improve water quality in city streams
¦	Provide services to growing areas
¦	Improve services to underserved and
redeveloping areas
¦	Renew systems beyond effective life
¦	Reduce potential for property damage
¦	Provide community-wide benefits
¦	Reduce safety hazards from system failures
projects under each level. Based on this comparison,
the city determined that it would be most cost effective
to create an optimized suite of alternatives composed
of wastewater treatment facility and collection system
projects from Level 1 and stormwater projects from
Level 2.
Columbia preferred this optimized program portfolio
for its integrated plan. The city estimated that its plan
would require $1.02 billion over 20 years for capital
and programmatic costs. To ensure affordability and
produce the greatest possible benefits to human
health and water quality, the plan proposed revising
assumptions every 5-10 years for project costs,
implementation dates, socioeconomic conditions, and
regulatory requirements.
The Columbia Wastewater and Stormwater Integrated
Management Plan was adopted by the Columbia City
Council in 2019 and implemented in the wastewater
treatment facility and storm sewer permits MDNR
issued in July 2020. In the permits, MDNR committed
to using the plan when making future regulatory
decisions. Columbia's wastewater treatment facility
permit required an annual progress report on any
proposed updates to the plan, the past year's
implementation activities, and the implementation
activities proposed for the following year.
For more information, visit EPA's integrated planning Report to Congress webpage at:
EPA-823-F-21-021 I June 2021