OSCODA – The public got a glimpse of the inter-workings of the Foote Dam Hydroelectric Plant, Saturday, during a centennial celebration held over the weekend.
Consumers Energy allowed 240 visitors to tour the dam at no cost on Saturday, Aug. 11, for 30 minute guided tours.
Built in 1918, Foote Dam was named after William A. Foote, the founding father of today’s Consumers Energy in 1886. The dam is responsible for supplying electricity to thousands of people all over the state of Michigan.
At 100 years old, the dam still has original parts including: turbines, generators and the control room devices. The equipment is all original but the methods of how to run the units has changed.
“The design life was probably 50 years,” said Manager of Renewable Generation Bill Schoenlein. “They continue to operate while being maintained”.
Schoenlein doesn’t have definite answers on how long the original parts will continue to run but he mentioned that they haven’t seen anything that would prevent them from running the dam for a long period of time.
The explanation for the original parts working almost 50 years longer than predicted as to do with a margin of safety in their construction.
“I think some of it is they used a much greater margin of safety in their engineering,” said Schoenlein “The design of things because of some uncertainty so they really wanted to have a factor of safety in engineering”.
In 1918, operators would operate the dam manually and often need to live close by in case something went wrong.
They would receive a signal on a light in their home to make them aware that they were needed at the dam.
Schoenlein also explained how moving water is used to generate electrical energy.
He explained that the water flows downstream and into a chamber around the unit. He explained that wicket gates are around the unit and they work together edge to edge and control the water flow from the unit.
Then the governors control the wicket gates which control the amount of water which will determine the output of electrical energy on the turbine.
“More water, more flow, more electric production,” said Schoenlein
The dam also has what is called the powerhouse or intake area.
There’s a section for spillway so anything that doesn’t pass through the dam will pass through the spillway. This is important because of what happened in old times when mills were used on rivers.
According to Schoenlein, some mills didn’t have spillways so the water exceeded the capacity of the mill and the mill got washed down the river. The spillway is created to prevent that from happening to the dam.
He said the dam produces 33,000 megawatt hours of energy in a year which equates the power used by roughly 10,000 homes according to Schoenlein. He said the amount of water flowing through the dam varies greatly with the river.
Schoenlein believes typically the AuSable river will flow at 1,000 cubic feet per second.
With such a powerful structure, consumers sees the importance of taking safety precautions for residents that visit the dam.
The front and back of the dam has a line of buoys that indicate an area of no access to the public.
They also have a horn used to signal to people who are downstream that a change in flow or a change in operation is about to occur.
Also, all of the hydroelectric projects are required to have recreational facilities so a once narrow walking are along the hillside has been transformed into a handicap accessible fishing site which was a $2 million dollar project according to Schoenlein
They must have affiliated recreation sites for the dam because federal energy regulatory commissioner’s requires a recreation facility and Foote Pond serves that purpose as well.
“It’s a draw certainly for wildlife,” said Schoenlein. “We’ve got nesting eagles and trumpeter swans have been reintroduced as well and they really flourish here versus the non-native species,” said Schoenlein.