Value of SWAMP’s Statewide Monitoring Programs

One of the key features of probability-based surveys such as the Surface Water Ambient Monitoring Program’s (SWAMP) Perennial Streams Assessment (PSA) is their lack of bias in the selection of sample sites. In the case of the PSA, each sampling location represents a known fraction of California’s stream network. This allows the State to produce statistically sound and cost-effective estimates of the condition of California’s perennial stream network.