Zebra Mussel Monitoring Program

Water-Quality Monitoring

Conductive temperature, pH, concentrations of calcium and dissolved oxygen, and other physiochemical water properties are critical for zebra mussel survival, growth, and reproduction. Collection of water-quality data assists in risk assessments for zebra mussel infestation and studies of population dynamics. Together with the zebra mussel occurrence and distribution data, the water-quality data we collect enhances our understanding of dreissenid mussel ecology and potential range in temperate, low-latitude waters.

We use automated water-quality data sondes to measure and record water temperature, dissolved oxygen, specific conductance, and pH at five-foot depth intervals—from the lowest depth to the surface—providing a spatial profile of water-quality conditions. Discrete water-quality samples are collected at a subset of sites and are kept below 5° C until shipped to the USGS National Water Quality Laboratory in Denver, Colo. The water-quality samples are analyzed for nutrients, common ions (such as calcium), and alkalinity. Water-quality data has been averaged from all sites at each study area and are available by choosing a study area from the locations tab on the navigation bar.

At Reservoirs

Hydro Tech deploying EXO2 sonde for water quality measurements

In addition to data from automated water-quality sondes, discrete water-quality samples are collected using standard USGS protocols at a minimum of two discrete points in the water column at selected sites. Discrete water-quality samples are analyzed for alkalinity, major ions (calcium, chloride, fluoride, magnesium, potassium, silica, sodium, and sulfate) and nutrients (nitrogen, nitrites, nitrates, phosphorus, and orthophosphate).

At Rivers and Creeks

Over the shoulder view of Hydrotech standing on a large bridge, lowering sampling equipment off the side of the bridge

Water-quality sondes are used to measure basic water-quality characteristics (water temperature, dissolved oxygen, pH, specific conductivity) from rivers and creeks, usually by lowering the sonde down to the water from a bridge. All water-quality samples are stored in the USGS National Water Information System (NWIS).