The Clean Water Act of 1972 as amended in 1987 mandated that eachstate
control the non-point source pollution flowing into its local rivers.
Non-point source pollution is pollution that comes from an unknownor
diffuse source. Urban storm water carries a variety of non-point sourcepollutants
(such as residential lawn treatment chemicals, oil and refuse foundon
city streets, etc.) into local rivers.

For the Tollgate Drainage District (see the accompanying pictures),
the Ingham County Drain Commissioner, Pat Lindemann, has developeda
unique solution to this pollution problem that is both environmentally
conscious and cost-effective. The solution involves the creation ofa new
wetland ecosystem designed to naturally clean and recharge the district's
storm water. The new ecosystem is commonly referred to as the Tollgate

The storm water that drains from the Tollgate Drainage District will
be diverted to the Tollgate Wetlands where it will be naturally
cleansed of pollutants and then recharged either into the air or
ground with little, if any, storm water flowing into local rivers.

The project will be to construct a model of the Tollgate Wetland
detention system (east of the Grosbeck golf course) driven by
statistical weather history. This model will be used to calculate the
storm water handling capacity of the ecosystem and predict the
concentration of various pollutants and the amount of water flowing
into local rivers. In particular, the model should take into accountthe
various uptake potentials of native plants. There are certain plants,
like broad leaf arrowhead, that literally throw water in the air.

The ideal completed project deliverable would be computer program in
a modern portable language that implements the model. It is highlydesirable
that the model and program be well documented and constructed so that, as
the ecosystem changes, the model and the program can be modified toreflect
these changes.

Since the Tollgate wetland development is a prototype for future similar
projects, it will be highly desirable that the model and program be
modular in construction so that both may be reused and recycled inthe
future for other wetland projects similar in concept to the Tollgate

There will be an opportunity for the results of this project to be
presented at a national conference.

This summary prepared with the assistance of E. Schertzingand the
"Tollgate Wetlands," P. E. Lindemann, published by theIngham County Drain
Commissioner's office.