Lake Mauvaise Terre Nutrient Reduction Initiative – Plan Implementation & Construction

Synopsis

Effective source water protection requires upfront planning and targeted on-the-ground treatments. Northwater developed a comprehensive watershed plan for Lake Mauvaise Terre, a back-up water supply for the City of Jacksonville in central Illinois. The plan utilized modeling, assessments, and landowner outreach to identify a suite of practices that would maximize nutrient and sediment load reductions. Working with the city and local farmers, a funding request was submitted to construct practices detailed in the plan. Almost $700,000 in funding was secured in 2015 and Northwater was retained to manage all aspects of the project including, survey, design, and engineering.

Client(s):

City of Jacksonville, IL, American Farmland Trust
Completion Date:

2017
Services:

Geosciences & Engineering, Water Resources, Water Supply
Market/Sector:

Agriculture, Government
Location:

Morgan County, Illinois

Project Description

Lake Mauvaise Terre is the back-up water supply for the City of Jacksonville, Illinois. It is impaired for numerous constituents, including phosphorus and sediment. Northwater was retained as the lead consultant to assist the American Farmland Trust (AFT) and city in executing an Illinois EPA funded Section 319 grant for planning and project implementation. Immediately following completion of a watershed plan and supplementary streambank erosion and in-lake dam feasibility study, Northwater helped to secure almost $700,000 in funding to install more than 200 individual treatment practices.

Northwater oversaw all implementation activities including engineering and design, administration, construction oversight and inspection, and project management. Over a 2-year period, more than 200 individual practices spanning 66 project sites were surveyed, designed, and constructed, more than originally proposed and under budget. Practices installed included:

Over 24,000 feet of water and sediment control basins
Over 19 acres of grassed waterways
420 acres of cover crops
17 grade control structures
Over 2,000 feet of low gradient surface drains
2 sediment basins and 1 pond
1 Livestock waste treatment system

It is estimated that this project achieved annual load reductions to the lake of 4,534 lbs for phosphorus, 16,674 for nitrogen, and 2,274 for sediment, substantially higher than originally projected.