37,000 population
Bike path over the Ottawa River.
Photo courtesy of City of Lima.
The City of Lima, in northwestern Ohio, is home to about 37,000 people. A
combined sewer system serves about 60 percent of the city. The other 40
percent is served by separate sanitary sewers and storm sewers. Wastewater
from the combined and separate sanitary sewers is conveyed to the city's
wastewater treatment facility.1 Treated wastewater from this facility and
stormwater discharges flow into the Ottawa River, a central feature for the town.
The 4.2-mile Ottawa River Bikeway winds alongside the river and connects the
city's parks, the downtown business district, and the local high school.
Lima experiences sanitary sewer overflows (SSOs) and combined sewer
overflows (CSOs) mainly due to inadequate capacity at the wastewater
treatment facility during storms. Under a 2015 consent decree with the U.S.
Environmental Protection Agency (EPA) and the state of Ohio, the city agreed
to make major structural improvements to control CSOs and to eliminate
sewage overflows from the sanitary sewer system. Lima also must comply with
permit limits for nutrients, sediment, and bacteria entering the Ottawa River.
The potential cost to address these issues traditionally exceeded the financial
capability of the city and its residents.
EPA Region 5
Integrated Planning in Action
City leaders thought it was not feasible to rapidly raise utility rates to quickly accomplish the needed
improvements agreed to in the consent decree, particularly in light of Lima's declining population and other
economic challenges. Lima decided to develop an integrated plan to change the sequence of projects to achieve
the greatest environmental benefits first while avoiding large rate increases.
Lima modeled a variety of control options within the collection systems, at pump stations, and at the wastewater
treatment facility to determine which sequence of controls would achieve the greatest environmental benefits at
an affordable cost. The city devised a draft plan, then engaged the public. Lima updated the public on its draft
and final proposals through city council meetings, neighborhood association meetings, chamber of commerce
meetings, and meetings with other stakeholder groups.
1 "Wastewater treatment facilities" (WWTFs) is a generic term for facilities that treat or manage wastewater, including publicly owned
treatment works.

The resulting integrated plan proposed first expanding
treatment capacity at the wastewater treatment facility,
then installing controls (i.e., sewer separation, real-time
control, tank and pump station improvements) that
would capture more than 97 percent of CSO volume,
and finally conducting separate sanitary system
upgrades such as pump station improvements to
reduce SSOs. Lima prioritized the CSO projects over
SSO projects because CSO volume was substantially
higher than SSO volume and the CSOs had a greater
potential for direct human contact.
The total capital cost of the integrated plan projects
was estimated at $147.6 million over 28 years:
substantially less than the city would have had to
spend without using an integrated planning approach,
while still meeting the performance criteria contained
in the consent decree. By expanding capacity at the
wastewater treatment facility first, the city was able to
reduce CSOs faster and at a lower cost than if it had
not developed an integrated plan as part of its consent
decree. Through the implementation of the integrated
plan, Lima anticipated it would significantly reduce
the amount of bacteria, nutrients, organic matter, and
suspended solids entering the Ottawa River.
Lima's integrated plan was included in an EPA consent
decree in 2015. In 2018, Lima increased its wastewater
treatment facility's wet weather capacity from 53 million
to 70 million gallons per day and eliminated untreated
bypasses. The city also designed a storage basin that
is expected to further reduce CSOs to the Ottawa River
when construction is completed.
Ottawa River Bridge bike path. Photo courtesy of City of Lima.
For more information, visit EPA's integrated planning Report to Congress webpage at:
https://www.epa.qov/npdes/inteqrated-planninq-municipal-stormwater-and-wastewater	EPA-832-F-21-018 I June 2021