Elkhorn Slough National Estuarine Research Reserve (ESNERR), the Elkhorn Slough Foundation (ESF), and the Monterey County Water Resources Agency have been supporting a volunteer water monitoring program since 1988. Twenty-four stations (see map) are sampled monthly for temperature, salinity, dissolved oxygen, pH, turbidity, nitrate, ammonium, and dissolved inorganic phosphate. The data are collected in the field by a singularly dedicated and reliable volunteer, Sue Shaw, with assistance from other volunteers.

In 1997, Jane Caffrey (the ESNERR research coordinator at that time) and collaborators analyzed the water quality data collected from 1988-1996. They also referenced water quality data collected in the 1970s in the same region. Click here to download their complete summary report (310 KB .pdf file).


Some trends observed from this data include:

- a significant increase in nitrate concentrations since the 1970s
- extraordinarily high nitrate concentrations in the lower Salinas River which may be the highest recorded in scientific literature for a river or estuary
- concentrations of ammonium that are an order of magnitude lower (or more) than nitrate
- low concentrations of dissolved oxygen in some areas which have restricted circulation
- opening of the Salinas River lagoon leads to rapid increases in salinity in the lower river even during the rainy season when river discharge is high

To request a copy of the some or all of our volunteer monitoring data, download and print the request form (145 KB .pdf file) and fax it to us. Please describe the project for which you need the data and sign the waivers both acknowledging that the data may contain errors and agreeing to request our permission before further dissemination of the data. Upon completion of these forms, we will email you the data in an Excel spreadsheet.

Water quality scientist to contact regarding these programs:
John Haskins