Macomb County Bio-swales and Rain Garden

The Macomb County Public Works office received a Clean Michigan Grant in 2001. The goal of the grant project was to incorporate a variety of low impact development (LID) techniques into the site plan of the Macomb County Public Works Office. Installation of low impact development techniques allows for storage, filtration and infiltration of stormwater runoff that will reduce peak flows and pollutant loading to the Clinton River.

As design of the LID techniques proceeded, a number of challenges were encountered. The new Public Works Office site design was complete and work was progressing at the site during the preliminary design of the LID techniques. The County determined that it was cost prohibitive to modify any of the site work that was currently under construction. Therefore, the LID techniques had to be incorporated into the existing site design without modifying the site layout including parking layout and building location or significantly modifying the grading plan.

Three LID techniques were installed as a part of this project including a rain garden, bioswale and approximately 525 square feet of pervious pavers. The rain garden, located adjacent to the building, accepts drainage from approximately one third of the roof. The surface area is approximately 350 square feet and covered with a mixture of shrubs and wildflowers. It is anticipated that the rain garden will provide removal of 57 pounds of sediment, 0.14 pounds of phosphorus and 0.65 pounds of nitrogen annually.
The bioswale, located along the north edge of the site accepts drainage from the parking lot. The swale is approximately 270 feet long. The bottom channel of the swale was planted with native grass seed and the upper banks were planted with flowering shrubs and wildflowers. It is anticipated that the bioswale will provide removal of 629 pounds of sediment, 1.7 pounds of phosphorus and 6.5 pounds of nitrogen annually.

Approximately 525 square feet of pervious pavers were installed on the south side of the building. It is anticipated that the rain garden will provide removal of 8.5 pounds of sediment, 0.02 pounds of phosphorus and 0.11 pounds of nitrogen annually.

Special thanks to UniLock, DecraScape and Clinton Township. Without these important project partners, the LID techniques demonstrated at the Public Works Office would not have been possible. UniLock donated the pavers and retaining wall bricks for the porous paver sidewalk. DecraScape donated all the base materials and installation for the porous paver sidewalk. Clinton Township assisted with the construction of the rain garden and grading preparation for the porous pavers.

 

Bell Forklift Building Brownfield Transformed

Macomb County also practices what it preaches in terms reviving brownfields into environmentally friendly sites.
On the south side of the Administration Building in downtown Mount Clemens was the former brownfield site of the now demolished Bell Forklift Building.

It has been transformed into an environmentally sound site that captures, holds, and filters storm water from wet weather events. The site is also superior to traditional parking lots because it allows road salt, automotive oils and fluid leakages, and other debris from draining directly into the Clinton River by using.

Four “rain gardens” and approximately 400 linear feet of biologically-engineered swales (bio-swales) have been constructed on the site and utilize native plant materials that are very effective at holding storm water in deep root systems and filtering out negative pathogens and pollutants.

This project was constructed in 2007 and assists in alleviating the crowded parking conditions near the Macomb County Government Campus. The rain gardens and bio-swales are completed and include all native Michigan plant materials that will take up to 2-3 full years to mature.

Some of the realized benefits by including the use of native species are that they require little to no watering or fertilization, have greater storm water detention and absorption which lessen the chances of flooding and pollutant discharges into the Clinton River and Lake St.Clair.

The price of the project was very similar in cost to a conventional development, but less maintenance over the lifetime of this site will realize a more significant savings. Business owners, local government representatives, and the general public are invited to make a stop at this site, which is north off of Terry Street between Main Street and Northbound Gratiot Avenue just south of Cass/Crocker Avenue in Mount Clemens.

Bio-swales sign.

Middle Branch of the Clinton River Streambank Stabilization Project.

Macomb County BMP Projects.

Rain Garden sign.