The community of Wesley Chapel, FL has experienced growth in population of over 150% between 2001 and 2021, during which areas surrounding the Boyette Road Reclaimed Water Reservoir have seen rapid, high-density residential construction. The 500 MG reservoir is impounded entirely by an earthfill dam classified as a high-hazard potential structure. In 2023, hydraulic modeling and subsequent inundation mapping were used to identify at-risk areas downstream to update the Emergency Action Plan (EAP) originally produced upon the reservoir’s completion in 2015. The process revealed challenges to modeling current and future conditions in a rapidly developing landscape in order to ensure accuracy and maximize benefits for emergency responders.
The hydraulic modeling performed for EAP inundation mapping required the collection of various GIS data, such as topography, stormwater infrastructure, and land use. Data available from 2018 or more recently was initially considered to be a valuable depiction of the landscape. Further inspection revealed that high-density residential construction has, and continues to, spread across the landscape and these GIS datasets reflected what was historically agricultural land. Several resources were tapped to capture ongoing downstream development and produce inundation maps that would be useful to the community in years to come. This effort included coordination with the County Planning Department and local developers to obtain grading plans of new communities, collection of on-site photographs and measurements, and evaluation of 2023 aerial imagery for incorporation into the hydraulic model.
An emergency planning tabletop exercise was held with county staff and emergency responders following the EAP update in 2023. Holding this exercise prior to publication of the EAP allowed the dam owner and emergency responders to understand new and future impacts of downstream development on the community. This also allowed emergency responders to voice what they considered pertinent information to include on the inundation maps, which guided the approach and level of detail undertaken in hydraulic modeling. This presentation will outline the implications to downstream consequence identification and emergency planning of positioning a reservoir within a landscape evolving due to human development. The Boyette Road Reclaimed Water Reservoir EAP will be used as a case study to further discussion on solutions used to produce practical, beneficial inundation maps and EAP responses based on current or near-future conditions.
