Public-Private Link Automates Stormwater Pond Management

Abstract

"The pond's at the right level, a rain event is coming, the pond says it's time to open, it opens, it discharges and then the next day when that big rain event happens it almost exactly captures all of it."The pond is fitted with Smart Pond technology, developed by OptiRTC and installed via an agreement with the Florida Dept. "In between storms, that pond is actively managing its water levels to maximize water quality treatment."The state agreement with NST provides access to thousands of ponds in Florida, Littlejohn said, with plans to actively develop 12 to 20 more ponds in 2022. "We could have entire neighborhoods saved from flooding if you have enough ponds retrofitted that could be actively drained down to prevent a flood." Comparing modeling for the original pond designs and models for the retrofitted Smart Ponds shows 44% more water quality treatment and 84% more flood attenuation volume, Littlejohn said. Beneficiaries are entities such as Port Tampa Bay, he said, which can purchase water quality treatment in a Smart Pond instead of building its own pond. Patrick Blair, Port Tampa Bay, vice president of engineering, sees in Smart Ponds a middle ground between conventional ponds that take up lots of land and expensive vaults that store lots of water. At $200,000 to $300,000 per retrofit, Smart Ponds are cheaper than the $650,000-per-acre-foot vaults but more expensive than conventional, passive stormwater ponds. "What we're going to get after a few months or several rain events is what the actual runoff coefficient for the basin and how the pond reacts to that."In the case of the pond at Port Tampa Bay, missing the mark on the low side is OK, but a pond in a flood-prone neighborhood would need to be managed with a more conservative model, Littlejohn says.