What happened that day is that the retention basin filled up from the 5.1 inches of rain we received that day, causing the water to back up into the storm sewers and catch basins. By 9:00 p.m. some streets were covered from curb to curb with standing water that had no place to go until the retention basin eventually drained down later that night. In the meantime, the backed-up storm water escaped from the breaks in the two buried pipes and as the water receded, it sucked the surrounding sand into the pipe, causing a small sinkhole behind 49995-50011 Regent and a much larger sinkhole between 49992-50008 Watling.
The Association hired a contractor who managed to get the storm sewer pipe at the smaller sinkhole repaired later in the fall of 2014. However they found that the pipe at the larger sinkhole was much deeper and after an initial attempt had to be abandoned, they brought in heavy equipment last week to make the repairs.
In both cases, it's believed that the breaks in the plastic storm sewer pipe were caused by construction debris that was dropped directly onto the pipe during the backfilling of the storm sewer trench in 2004.
Landscaping repairs at the smaller sinkhole have already been made and the Board of Directors intends to have the landscaping repaired at the Watling sinkhole sometime after Labor Day.
Below are photos of the Watling sinkhole repairs that were made on Aug. 13, 2015.
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| The excavator had to dig a hole about 7 ft. deep and 12 ft. wide to expose and repair the broken storm sewer pipe. |
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| The worker's foot is next to the break in the storm sewer pipe. |
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| The broken section was cut out and replaced with a new section of 12 in. diameter pipe. |
