Analysis of Hydrologic Data

Southwest Florida Water Management District: Analysis of Hydrologic Data to Support Minimum Flows for Rivers in West-Central Florida

The project objective is to assist the SWFWMD with the analysis of hydrologic data associated with rivers in west-central Florida for the purpose of setting minimum flows in these water bodies. While establishing minimum flows is technically and administratively complex, the scope of this project is limited to using defensible statistical procedures to help interpret the historical data record. HSW was awarded this contract to complete tasks and proposed or implemented statistical procedures under the scope of work and include the following:

1.  Determine if stream flow is changing over time – hydrograph analysis, single and double mass
analysis, regression and Mann-Kendall tests.
2.  Determine frequency and duration of inundation – generate duration of inundation curves.
3.  Develop synthetic hydrograph for short-term gage using relationship between short and long
term gage data – Used a systematic sampling procedure to limit serial correlation effects and a
piecewise polynomial regression procedure (programmed in SPSS) to identify association
between short and long term gage data. Generated duration of inundation curves from
synthetic hydrograph data.
4.  Calculate residence and flushing times for estuarine portions of rivers and co-authored two
estuarine mixing models (MERT and MMRT).
5.  Develop statistical models depicting association between river geometry, flow, tidal and
salinity.
6.  Estimate flow in ungaged portions of rivers using statistical association.