Monitoring & Gaging

Monitoring & Gaging

Balance Hydrologics manages and maintains numerous stream gaging stations and rain gages throughout California and Nevada, using standard USGS protocols. These site-specific primary data sets form the basis for more complex evaluations and analysis. At many stations Balance staff measure bedload- and suspended-sediment discharge, which adds to the understanding of the sediment process at work in the watershed. Balance performs both high-flow storm visits and periodic low-flow site visits to perform observations and measurements that are used to calibrate the automatically collected data.


Balance Hydrologics installs and manages over 150 web-accessible stream and rain gages throughout the San Francisco Bay Area, the Central Coast, and the Sierra Nevada Tahoe/Truckee/Reno area. Rainfall totals, flow, and water quality data from automated stations are downloaded and posted hourly to our website ( Real-time access can be available to the public or limited to authorized users. A standard streamflow-gaging station usually consists of a continuously-recording datalogger with sensors for direct measurement of water depth, specific conductance, and water temperature. Depending on client needs, other sensors can be added to a station to measure (among others) turbidity, pH, DO, precipitation, and/or air temperature. Balance staff manage all aspects of the gaging – project permitting, installation of stream gaging equipment, station maintenance, real-time web access set up and maintenance, streamflow-rating curve development and updating as conditions change. Daily flow averages, peak flows, and any other observations and measurements are generally summarized and submitted to the client in a year-end hydrologic report.

Examples of gaging objectives include:

  • Complying with California Water Board diversion and bypass monitoring for land managers, farming communities, and non-profit organizations;
  • Enhancing baseflow management of instream diversions under the California Department of Fish and Wildlife (CDFW) Coastal Salmon Recovery Program by providing diverters and CDFW staff with real-time access to stream flow conditions;
  • Management of reservoir operations and downstream stream habitats by water districts and purveyors;
  • Facilitating communications amongst multidisciplinary teams for permitting of large projects.