This is the first in a series of articles on project priorities from the Dunlap Lake 20-Year Master Plan. The top priority identified is updating the spillway on the 80-year old dam.
With storm events and impervious surfaces increasing water flow everywhere, IDNR wants Dunlap Lake property owners to increase the size of the spillway constructed in 1946. The aging spillway has required repairs in 1963, 1972, 1990, and then again in 2016 when there was a partial chute failure.
IL Dam Safety Engineer Paul Mauer came to Edwardsville on March 24, 2021. He covered a variety of topics including the capacity issues that first came to light in a 1978 study, why he thinks the spillway should be expanded from 35 feet to 96 feet, and possible liabilities for residents if nothing is done.
In his summary to residents Mauer said, “You have a valuable asset, but it does require maintenance, it is going to require some cost.”
He stressed that costs can accumulate if maintenance is not addressed. “The quicker that it is brought into the condition we would like it to be in, the faster you will stop having that accumulation of costs because of deferrals,” explained Mauer.
The physical limitations have made this challenging, but Hurst-Rosche Engineering has designed a structure that can achieve the requirements of the IDNR at the northeast corner of the dam. It also allows the association to incorporate another gate into the structure that allows for a much safer lowering of the lake than the current gate.
The proposed assessment increase gives the association an ongoing funding stream to care for aging infrastructure, and provides match money for grants and additional improvements identified in the 20-year masterplan (to be covered in additional articles).
If you have questions for IDNR or the DLPOA Board, you can reply to this message or leave them on the Q&A at www.dunlaplake.org/vote/.