Hewitt Creek is a 23,005-acre subwatershed of the 592-square-mile North Fork and 1,879-square-mile (1.2 million acre) Maquoketa River basin.
The Hickory Creek branch originates near Bankston joining Hewitt Creek in Section 21, New Wine Township, and flows to the North Fork Maquoketa River in Dyersville. The watershed is 1.2% urban, 91.2% agricultural and 7.5% woodland.
The 2002 Iowa DNR Section 305(b) water quality assessment report identified the lower 4.4 miles of Hickory Creek as “partially supporting” of aquatic life use based on the number and types of macro invertebrates and fish species collected. This stream segment was listed on Iowa’s EPA section 303(d) impaired waters list (Part two – one or more pollutants and Part five – biologically-impaired).
Hewitt Creek ranked sixth among 25 similar size Maquoketa River subwatersheds indexed for their delivery of sediment, total nitrogen and phosphorus. It also delivered relatively high concentrations of fecal coliform bacteria.
History, Mission and Project Goals
In 2004, Hewitt Creek watershed residents took part in a public meeting to address water quality issues in response to the listing of the Hickory Creek on the 2002 impaired waters list.
Two actions then led to active citizen involvement in a watershed-wide effort to address the issues.
First, Iowa Farm Bureau Federation baseline funding arrived shortly before the 2005 planting season to be used to demonstrate local development and implementation of a watershed water quality improvement plan.
At the same time, a group of watershed residents attended several meetings to discuss potential uses of the incentive funding, and to organize a watershed council as an Iowa non-profit corporation.
The council evaluated water quality and environmental management issues and worked to establish watershed performance goals.
Using the IFBF funds, the council established a set of modest incentives in 2005 to link management practices to desired environmental outcomes.
Two other activities marked that first year in the watershed project: completion of a pre-project survey of landowners by the ISU Sociology Department and a field day June 21 at the farm of John Rubly.
The first year Farm Bureau incentives were used for testing technologies that measure the environmental and economic results — or performance — of various field and farm management practices. The first measures adopted for incentives aided in refining manure and commercial fertilizer use.
About 5 percent of the Farm Bureau grant was used to complete monthly normal flow and rain event high flow water analysis (see reverse side).
In 2005, the council submitted an application for a state funding grant of the project, through the then-new Watershed Improvement Review Board. The application was approved and the council received WIRB funding for a three-year project, 2006-2008.
Iowa Watershed Improvement Fund grant money allowed the council to assemble a BMP menu together into the science-based and state agency adopted performance indexes, P-index, Soil Conditioning Index (SCI), and the cornstalk nitrate test. The indexes are calculated on individual fields, weighted by field acreage to attain a farm index, and the 46 cooperator farms are combined to attain a measure of watershed performance.
WIRB money allowed the council to expand its incentive program and continue with monitoring, both of which were central to the project.