New Tiger Bay weir offers both water quality and quantity benefits

“This weir project has multiple benefits to water quantity and water quality, two of the district’s core mission areas,” said St. Johns River Water Management District Executive Director Dr. Ann Shortelle. “By holding back stormwater, the project rehydrates a stressed wetland and recharges groundwater and Indian Lake. What’s more, the wetland will treat the stormwater and decrease nutrient loading to the river.”

The new weir is designed to hold an additional three feet of water in a wetland system that has been stressed by low water levels. Water stored by the weir will rehydrate the 150-acre wetland, enhance recharge to the Upper Floridan aquifer and directly benefit the hydrologically connected Indian Lake. Up to 3 million gallons of water per day (mgd) are projected to recharge the aquifer system and Indian Lake.

Also, stormwater captured by the weir will no longer drain to the Tomoka/Halifax river system. That water will be treated in the wetland system and decrease downstream nutrient loading to the naturally brackish (slightly salty) river.

Meantime, the city of Daytona Beach has implemented a new wellfield operation protocol that restricts pumping near the wetland in order to address potential impacts to both the wetland and Indian Lake. The city will re-equip and connect a large capacity well located east of Interstate 95 to its wellfield system later this year.

Background

The Tiger Bay Canal was constructed for drainage purposes prior to 1943 near Indian Lake. The canal ultimately discharges to the Tomoka/Halifax river system. Historically, a long-term average of 11 mgd of stormwater flowed through the Tiger Bay Canal where it is crossed by the Indian Lake bridge.

Indian Lake is one of the waterbodies addressed by the Minimum Flows and Levels (MFL) Prevention/Recovery Strategy for Volusia County. The lake has a set minimum flow level and is in recovery status.