Summary of hydrologic conditions in the Reedy Creek Improvement District, central Florida

The Reedy Creek Improvement is an area of about 43 square miles in southwestern Orange and northwestern Osceola Counties, Florida. A systematic program of hydrologic data collection in the Reedy Creek Improvement District and vicinity provided data for assessing the impact of development, mostly the Walt Disney World Theme Park and related development on the hydrology. Data collected include stream discharge, water quality, groundwater levels, lakes levels, and climatological. Rainfall has been less than the long-term average in the Reedy Creek Improvement District since development began in 1968. The deficient rainfall has reduced stream discharge, lowered groundwater and lake levels, and possibly affected water quality in the area. Groundwater levels and lake levels have declined since 1970. However, the coincidence of below-average rainfall with the period of development makes it impossible to assess the effect of pumping on declines. Occurrence of toxic metals does not relate to development, but distribution of insecticides and herbicides does appear to relate to development. Specific conductance, phosphorous, and nitrate concentrations have increased in Reedy Creek since 1970, probably due to disposal of treated wastes. (USGS)