Surface Water Quality & Stream Condition Index Evaluation

Stream Condition Index 01 Stream Condition Index 02 Stream Condition Index 03

Water & Air assisted the Florida Department of Environmental Protection (FDEP) in data collection efforts to support agency review of the surface water criterion for dissolved oxygen and to provide data for Florida’s Total Maximum Daily Load (TMDL) and National Pollutant Discharge Elimination System (NPDES) programs. Using stringent quality assurance procedures, Water & Air collected environmental data quarterly from 130 of the 342 project stations located throughout the state. Water & Air personnel received in-house training by FDEP staff for water and biological sample collection and habitat assessment. Water & Air field personnel successfully passed FDEP audits intended to ensure that field data measurement and biological and water sample collection procedures were consistently applied.

Task Summary

  • Performed field reconnaissance of sampling locations to select site-specific sampling points and develop strategies to install expensive instruments in a secure, safe, and scientifically valid manner.
  • Installed YSI instruments to record water quality data in 15-minute intervals at each station for four days each quarter.
  • Collected water quality samples to determine nutrient levels at each station.
  • Evaluated streams using Florida’s Stream Condition Index methods that include stream habitat assessment, collection of benthic macroinvertebrate samples, and water column physico-chemical measurements.
  • Sampled sediments, periphytic algae, and benthic macroinvertebrate, to enable evaluation of relationships between biological and water quality data.


Water & Air delivered legally defensible water quality and biological data to the State of Florida. FDEP used these data to evaluate and revise surface water quality standards. Data were used to supplement and support water resource decision making within the Florida TMDL and NPDES programs and to refine methods for stream condition evaluation requirements in the Quality Assurance Rule. These programs are intended to maintain or improve water quality in Florida streams, rivers, and lakes.

Contact Us

6821 SW Archer Road
Gainesville, FL 32608

800.242.4927 (Toll Free)
352.378.1500 (Fax)

Schedules: 899-1 & 899-8

CAGE Code: 9U915