On Monday, the Township Board approved engineering work to replace a storm drain that has caused sinkholes and sagging on yards and pathways along the road south of Comstock Street. The Prein & Newhof firm will provide engineering services at a cost of $25,150.
Separation in the storm pipe joints is causing soil to enter the drain, Township Manager Bill Cargo explained, causing issues along about 317 feet of drain near the LightCorp and Shape Corp. manufacturing facilities.
For more than five years, township officials attempted to fix it by wrapping the gaps in the pipe, injecting mortar and installing steel bands, but the remedies did not work.
The project will entail replacement of about 154 feet of 60-inch pipe with 54-inch pipe, and replacement of another 163 feet of 48-inch storm pipe.
Cargo said the sinkholes do not currently pose a threat to public safety, but could if the issue is not resolved. The pipe has maintained positive pressure, he said, as water and soil are entering it.
The new pipe will contain premium O-ring joint material that was not available when the pipe was first installed around 1998. The construction cost is estimated at $149,000.
Bids are expected to be taken in 2020 for the Grand Haven Township Downtown Development Authority-funded project.