Repurposed Wetlands - A Case Study of a Reconstructed Urban Stormwater System along East Central Florida’s Halifax River
Presentation Type
Invited Speaker
In Person or Zoom Presentation
In-Person
Status
Invited Speaker
Invited Speaker Institution/Department
Bethune-Cookman University, Department of Integrated Environmental Science
Presentation Description/Abstract
Wetlands play a critical role in functioning watershed systems. They act as natural sinks for absorbing excess water, mitigating flood risk while also removing and sequestering surplus nutrients, pollutants, and sediments from stormwater runoff before it enters other water bodies. In highly urbanized areas, impervious surfaces restrict runoff infiltration, exacerbating flooding and pollution impacts. The Halifax River, an urbanized estuarine lagoon system located in East Central Florida and an important part of the broader Halifax watershed, is encompassed by large portions of impervious surfaces in the adjacent cities. In this case study, an existing detention pond connected to the Halifax River outfall canal system was retrofitted with a stormwater treatment system to help improve filtration of pollutants and excess nutrients. This project details the planning, construction, and in-situ water quality data collection and monitoring, documenting the before, during, and after impacts of the treatment wetland’s construction. The initial monitoring began in Winter 2017 and concluded post-construction monitoring in Summer 2019. Remote sensing images from Dec. 2017, Nov. 2019, Nov. 2021, and Jan. 2023 were downloaded from the USGS Earth Explorer and analysed with vegetation indices (NDVI) to evaluate the wetland’s long-term productivity trends and current conditions. Additionally, single and multivariate statistical analyses were conducted with the water quality data, such as salinity, TKN, and NO3, and evaluated across the project’s stages (pre-, during, and post-restoration). The remote sensing analysis indicates development and maturation of the wetland vegetation, while multivariate analysis shows significant differences in water quality variables post-restoration compared to those collected at the pre- and during stages. Treatment wetlands can better support urbanized areas, particularly when retrofitting the existing system, reducing hazard and pollution impacts while creating hotspots for biodiversity and increasing watershed functionality.
Keywords
Halifax River watershed, outfall canal system, treatment wetlands, stormwater runoff, urban stormwater, East Central Florida
Repurposed Wetlands - A Case Study of a Reconstructed Urban Stormwater System along East Central Florida’s Halifax River
Wetlands play a critical role in functioning watershed systems. They act as natural sinks for absorbing excess water, mitigating flood risk while also removing and sequestering surplus nutrients, pollutants, and sediments from stormwater runoff before it enters other water bodies. In highly urbanized areas, impervious surfaces restrict runoff infiltration, exacerbating flooding and pollution impacts. The Halifax River, an urbanized estuarine lagoon system located in East Central Florida and an important part of the broader Halifax watershed, is encompassed by large portions of impervious surfaces in the adjacent cities. In this case study, an existing detention pond connected to the Halifax River outfall canal system was retrofitted with a stormwater treatment system to help improve filtration of pollutants and excess nutrients. This project details the planning, construction, and in-situ water quality data collection and monitoring, documenting the before, during, and after impacts of the treatment wetland’s construction. The initial monitoring began in Winter 2017 and concluded post-construction monitoring in Summer 2019. Remote sensing images from Dec. 2017, Nov. 2019, Nov. 2021, and Jan. 2023 were downloaded from the USGS Earth Explorer and analysed with vegetation indices (NDVI) to evaluate the wetland’s long-term productivity trends and current conditions. Additionally, single and multivariate statistical analyses were conducted with the water quality data, such as salinity, TKN, and NO3, and evaluated across the project’s stages (pre-, during, and post-restoration). The remote sensing analysis indicates development and maturation of the wetland vegetation, while multivariate analysis shows significant differences in water quality variables post-restoration compared to those collected at the pre- and during stages. Treatment wetlands can better support urbanized areas, particularly when retrofitting the existing system, reducing hazard and pollution impacts while creating hotspots for biodiversity and increasing watershed functionality.