Complementary to the existing long-term water quality monitoring program, the NERRS implemented a new nutrient and chlorophyll monitoring program in 2002. The two sub-components of this program include monthly grab sampling at each of the four water quality stations, and diel sampling once a month at one site. All collected grab and diel samples are analyzed for concentrations of ammonia (NH4), nitrite (NO2), nitrate (NO3), phosphates (PO4), silicates (SiO4) and chlorophyll a.