If you walk along the west shore once you pass the dock you will get to the trail where the wooden fence is...
Take the cement trail where the cattails open up...
That is considered the dam...
Stay on that road and it will curve around the lake and head by the golf course...
Once you get to the golf course the trail leads to the east shore etrance...
Here is a website dedicated to the park...
http://www.angelfire.com/falcon/kmhrp/habitats.html
The second photo from the top shows the dam...
There is a photo that has a man holding binoculars that shows the dam up close...