Fourmile Creek Watershed Management Authority

The Fourmile Creek Watershed is located in south central Iowa, as shown in Figure 2-1. The majority of the watershed is located in Polk County, with small areas in Boone and Story counties. The watershed is made up of both rural and urban areas, including the cities of Slater, Sheldahl, Alleman, Elkhart, Ankeny, Bondurant, Altoona, Des Moines, and Pleasant Hill. Fourmile Creek is a tributary of the Des Moines River, which flows into the Mississippi River. The length of the main stem of the creek is approximately 38 miles. The watershed is approximately 23 miles long and 5 miles wide and has an approximate area of 119 square miles, based on natural topography, and 116 square miles when excluding the area that drains to Dean’s Lake. The watershed is identified with a 10-digit HUC number, 0710000801. The watershed can be divided into three subwatersheds, as shown in Figure 2-2, including Upper Fourmile Creek, Middle Fourmile Creek, and Lower Fourmile Creek.

Fourmile WMA Master Plan

Fourmile Creek has a history of flooding that has impacted property owners in the watershed. Flooding is the major concern expressed by property owners and citizens. After community members expressed their concerns and jurisdictions desired to have a better collaboration mechanism, the Fourmile Creek Watershed Management Authority (FCWMA) was formed to address these and other challenges.

The FCWMA was formed in the fall of 2012. This organization was established to provide a common voice and to facilitate inter-jurisdictional cooperation in working together on watershed issues and opportunities.  A master plan was developed in 2015 to begin addressing concerns within the watershed.  You can view the full master plan by clicking here.

Fourmile Creek Greenway Master Plan

The Lower Fourmile Creek Greenway Master Plan is one of the first steps in implementing the Fourmile Creek Watershed Management Authority’s vision for the creek.  Greenways are an integral part of a community fabric.  They provide connections between neighborhoods and local destinations.  They can provide vibrancy to a community which attracts and retains people of all ages.  They encourage alternative transportation and access to recreational resources and the natural environment.  They also play a critical role in protecting and enhancing a community’s water quality, as well as reducing flood risk and damage.  This master plan will address these critical components and identify potential recreational and educational amenities the greenway system can offer.

Definition of a greenway:

a linear corridor of open space along a waterway, promoting public health, safety and general welfare thru flood protection and water quality improvements. This greenway is intended to be land protected for environmentally sustainable purposes and may include passive recreation and educational amenities, cultural resources, urban agriculture, conservation, and non-vehicular transportation.

Explore the Master Plan

Click here to explore the Fourmile Lower Greenway Master Plan.

Fourmile WMA Meeting Agendas & Minutes

A Watershed Management Authority is formed when two or more eligible political subdivisions want to work together to engage in watershed planning and management. The political subdivisions can include a combination of cities, counties, and Soil and Water Conservation Districts. The requirements of a WMA include being located within a watershed no larger than an 8-digit Hydrologic Unit Code (HUC) watershed, notifying all eligible political subdivisions to participate within 30 days prior to establishing organization, a Chapter 28E agreement filed with the Secretary of State, and a Board of Directors.  The Fourmile WMA meets quarterly, and agendas and minutes can be accessed below.


April 2024 Agenda

April 2024 Minutes

January 2024 Agenda

January 2024 Minutes

October 2023 Agenda

October 2023 Minutes

July 2023 Agenda

July 2023 Minutes


Agenda and Minutes Archive

Board Member Representative Packet


Polk County, on behalf of the Walnut Creek Watershed Management Authority (WMA) is inviting experienced professional services teams (Consultant) to submit their qualifications for the development of the Walnut Creek Watershed 5-Year Implementation Plan. The Request for Qualifications (RFQ) can be found by clicking the following link. Submittal deadline is June 14, 2024 at 2:00PM. Walnut Creek Watershed 5 Year Implementation Plan RFQ