Hydrologic Investigation of the Phosphate-Mined Upper Saddle Creek Watershed West-Central Florida

03-118-203Final

The upper Saddle Creek basin is a rapidly developing watershed to the east of Lakeland, Florida along the I-4 development corridor. Saddle Creek is tributary to the Peace River, which has experienced significant stream flow decline in the last few decades. This project sought to construct a model that could be used to investigate the hydrologic conditions (historical and proposed) of this previously mined, urbanizing basin. Among the objectives of this study was the investigation of feasibility of creating large-scale wetland mitigation and ecosystem restoration on reclaimed mine land, and the reestablishment of a more historical hydrologic function of the Saddle Creek watershed. Another important objective was the demonstration of the calibration and utility of the FIPR Hydrologic Model, FHM, for large-scale mine reclamation. A supplemental contract provided for additional data collection and flood plain modeling of the upper Saddle Creek. This supplemental scope was added in response to concerns from regulatory agencies as to the effects this wetland mitigation might have on the hydrology of areas downstream. This report documents the findings of this investigation and is being submitted jointly to the funding agencies. It summarizes the collection of hydrologic data and current hydrologic conditions of the basin. The report describes model set-up and calibration for both the large-scale domain and the near-field detailed model of Saddle Creek. The model has been utilized in a predictive capacity for hydrologic assessment of ecosystem restoration plans. Seven major restoration alternatives or basin evolutions were investigated with the model as examples. Conclusions or recommendations as to the best restoration alternatives and scheduling of final hydrologic investigations for the engineering design phase are delayed pending agency input. The model has shown to be productive for analyzing hydraulic impacts and benefits associated with wetland restoration alternatives in the Saddle Creek basin. The model has also shown to be a useful tool in analyzing large-scale mine land reclamation hydrology. However, several fundamental hydrologic questions are posed concerning the hydrology of west-central Florida mined lands, reasons for observed flow declines and drainage of the surficial aquifer.

Patrick Tara et al., University of South Florida. November 2003.