What happened to Washago Pond?
At Washago Pond, a pipe beneath the water that is part of the control structure of the dam developed a leak and drained the pond. The water drained through the Regan Drain to the Huron River. The structure is considered a low hazard dam due to the fact any failure would not have an impact on people or other properties.
Our staff is following our previously established action plan and working with all relevant state agencies. We are currently evaluating options and developing a plan for the area. We will be providing updates to the public on our website as these plans are developed and implemented.
What is a control structure?
The control structure is what controls the water level in the pond. For Washago pond that is a vertical corrugated metal pipe under water. When the water level goes above the opening in the top of the pipe, the water drains down to Regan Drain. When the water level is lower than the top of that pipe, no water drains into the lower part of the Regan Drain and Huron River.
When will it be restored?
The area of Willow Metropark where Washago Pond once was is being restored to natural habitat. In May of 2021, the corrugated metal control structure at Washago Pond failed which drained the pond down to its more natural water level. Staff are working with the State of Michigan as well as partners at the Huron River Watershed Council to finalize plans for the site that includes removing the previous dam structure and restoring the area with native plantings. The Washago Pond dam has been on the Huron River Watershed Council’s list of potential dam removals to improve the health of the watershed. This redevelopment plan would provide improvements to the watershed as a whole including diverse habitat for fish, aquatic invertebrates and amphibians as well as providing a filtering effect for rainwater.
This rendering of the area is the working concept approved by the Metroparks Board of Commissioners in September of 2021, but final plans are still being developed through the permitting process with the State of Michigan.
What happened to all the fish and waterfowl that were there?
Water drained steadily and slowly over 24 hours through the water control structure into the Regan Drain and then into the Huron River. We anticipate that a large amount of fish were able to drain safely into the river. We did not encounter a large number of stranded fish on dry land or in the remaining pond.
Under guidance of the DNR Fisheries Division volunteers worked to net and transfer large fish (that were over 6”) to the Huron River.
Washago Pond did not provide any permanent waterfowl habitat previously. It was used by water fowl for transient feeding and bathing. There continues to be a large basin of water in the center of the pond that is still providing these resources for waterfowl.
Is the pond still draining or has it stopped?
The pond has finished draining and is currently at its natural equilibrium as part of the watershed. Water is supplied to Washago Pond through the Regan Drain. The Regan Drain is a small tributary that runs through Washago Pond and into the Huron River. The level of water flow in the drain is dependent on rainfall and will fluctuate and continue to change seasonally. Currently there is steady flow through the Regan Drain.
How often is the dam at Washago Pond inspected?
Washago Pond dam is inspected every 5 years and has an emergency action plan on file, as required by the state. Our Last inspection was in 2017. A small leak in the control structure was noted in previous inspections and has been monitored while staff developed a plan for how it should be addressed. The condition had remained unchanged in the last inspection, and the dam was reported as “fair overall condition” by the inspector.