Assessing native and non-native plant’s impact on stormwater quality

Stormwater Pond Study and Enhancements

Water quality in stormwater ponds is often negatively impacted by runoff carrying fertilizer, yard debris, and pet waste, leading to elevated levels of nutrients like nitrogen and phosphorus. Manatee County in Florida wanted to learn if plantings could improve water quality through natural filtering. And if so, this eco-friendly solution could be implemented at stormwater ponds across the state.

The County teamed with the University of Florida to study multiple scenarios of native and non-native plantings in a buffer zone around stormwater ponds. Our ecological restoration team implemented the plan by installing native plants at two stormwater ponds, ornamental plants another two, and kept two that were surrounded by turf in their current state. Our staff treated the non-native vegetation with approved aquatic herbicides to prepare planting areas for installation. We used pine straw and natural mulch between plants for water retention and as a weed barrier. We also provided follow up treatments to reduce invasive species.

With the six ponds to provide data sources, the County is conducting water quality assessments to determine results and inform future stormwater pond design.