Since 2014 Balance Hydrologics has implemented the Truckee Meadows Stormwater Monitoring Program for the Municipal Regional MS4 permit which includes the Cities of Reno and Sparks and Washoe County. The current program includes water quality monitoring at 15 stations including 4 urban outfalls and 11stations on tributaries to the Truckee River which drain urban areas of Washoe County and the Cities of Reno and Sparks. The Lower Truckee River is currently listed by the Nevada Division of Environmental Protection as being impaired by total dissolved solids, total nitrogen, and total phosphorus. TMDLs for these constituents were established in 1994 with recent review and future proposed revisions. Water quality in the river is of particular concern because the river is habitat for the Lahontan Cutthroat Trout, a federally-listed threatened species, and cui-ui, a federally-listed endangered species. The City of Reno is leading the effort for implementing a stormwater monitoring program for the larger regional permit area, primarily to monitor and assess current conditions, analyze trends, and identify improvements to the monitoring program and that will eventually lead to implementation of new stormwater management strategies for selected areas.
It is well documented that water quality parameters or pollutants in stormwater change depending on timing and condition of the hydrograph. For instance, higher concentration of contaminants may be observed on the initial rise of the hydrograph; however, higher loadings are typically associated with the peak of the hydrograph or over a wider range of the storm. Balance hydrologists continue to help transition the City from a concentration-based compliance monitoring program to a constituent-loading calculation and analysis program. Balance staff are instrumenting high-priority stations with automated samplers and continuous logging water-level probes in combination with establishing a stage-discharge rating curve for each site. Together, an accurate measurement of streamflow and constituent concentrations will yield pollutant loadings—a vastly better metric for evaluating ecosystem health. Results will provide a more accurate assessment of pollution loading to the Truckee River and facilitate a comparison between sites, watersheds or stormdrains and help further identify areas that require stormwater best management practices or controls. Balance was recently awarded a contract to continue this program into 2019.

City of Reno, City of Sparks, and Washoe County, Nevada
City of Reno
Truckee Meadows, Steamboat Creek and North Truckee Drain
Sampling & Analysis Plan (SAP), Stormwater, Water Quality
Monitoring & Gaging