The water-quality parameters of interest for the long-term Trends Monitoring include field parameters: temperature, conductivity/salinity, dissolved oxygen and pH; and lab parameters: fecal indicator bacteria; nutrient parameters; and sediment parameters.
Trend sampling is conducted on a weekly basis during the rainy season (late Fall, Winter and early Spring), and twice monthly during summer base flow conditions.This regular sampling is supplemented by continuous temperature data from long-term sites to analyze diurnal and seasonal variation.
The level of sample collection will afford documentation of seasonal and annual changes in water quality. It will also allow for the development of geometric means, which is a common way to display and analyze bacteria results (see Glossary). This program component will be carried for an initial three years with the anticipation that it will be continued for an additional 20 years, if not longer.
Sampling Locations
a. Tomales Bay sampling locations: Sampling
locations include four bay sites to represent areas of major
impact from freshwater inputs, as well as tidal conditions and
separation of the Bay. These four Tomales Bay
sites represent the outer, middle, inner bay, and "inner"-inner bay
(the wetland/bay interface).
b. Watershed sampling
locations: Eleven permanent tributary sampling locations have
been established. These sites are coordinated with the four existing
gauging stations on large tributaries (mainstem Lagunitas, Olema,
Walker, and San Geronimo); East and west shore sites include sites
with human land use activities, and at least one reference stream
that flows through sub-watersheds with minimal human land use
activities.
