Otter Lake Source Water Protection

Synopsis

Otter Lake is a 770-acre public water supply reservoir encompassing a 13,000-acre watershed. Owned and managed by the Otter Lake Water Commission, it serves a population of 17,000, including 8 towns and 2 water districts in 3 different counties with an average daily output of 1.8 million gallons. Northwater has been working since 2010 to improve lake water quality and reduce treatment costs by executing a host of various initiatives based on detailed lake and watershed characterization and strategic planning.

Client(s):

Otter Lake Water Commission
Services:

Water Resources, Water Supply
Market/Sector:

Agriculture, Government
Location:

Macoupin County, Illinois

Project Description

Northwater began working with the Otter Lake Water Commission (OLWC) in 2010 to design and implement a long-term program to address water quality regulatory impairments for the reservoir. The goal of the program is concurrently focused on improving the health of the lake to reduce water treatment costs and enhance the lake’s recreational value. The program has been successful in achieving full support for a public and food processing water supply designated use. As of 2014, aquatic algae and manganese have been delisted as regulatory impairments. The project was awarded the prestigious Water Source Protection award by the American Water Works Association (AWWA).

A comprehensive lake and watershed assessment, modeling and monitoring program identified and quantified sources and causes of the impairments. With this information and coordination with landowners, Northwater developed a detailed, multi-phase implementation plan and secured Illinois EPA Section 319 program funding for on-the-ground and in-lake treatment practices.

Planning projects to support lake and water management and improve water quality have included: lake and watershed assessments, shoreline erosion surveys, and an approved watershed management plan. A watershed plan was completed in 2016 in response to new funding requirements and a need to stimulate additional and innovative lake and watershed improvements moving forward. It synthesized past work and utilized advanced mapping and modeling to quantify lake nutrient and sediment loading and identify a host of new watershed and in-lake treatments. This effort immediately resulted in an $800,000 United States Department of Agriculture (USDA), Regional Conservation Partnership Program (RCPP) grant to fund conservation practices on agricultural ground.

Northwater Consulting has served as the program manager and has provided a complete package of services to support the ongoing program. To date, Northwater has helped the OLWC secure well over 1 million dollars of state and federal funding to improve lake water quality.