Regional Stormwater Monitoring Program Sampling

Science Center Objects

The Issue: The State of Washington issues Municipal Stormwater Permits to local governments in the Puget Sound region that require them to develop and implement a stormwater management program that reduces the discharge of pollutants and protects the quality of water in rivers, streams, lakes and Puget Sound. The permitees in partnership with the State need to measure whether water quality and watershed health is getting better or worse as a result of stormwater management. The monitoring is a critical component of the Status and Trends in Receiving Waters element of the Regional Stormwater Monitoring Program (RSMP).

How USGS will help: As members of the State's small streams and the nearshore sediment monitoring teams, USGS will help by (1) monitoring status and trends of water quality, physical habitat, sediment chemistry, and biological communities of small streams in the Puget Sound lowlands during 2015 and (2) monitoring nearshore marine sediment chemistry in the Puget Sound during summer 2016. In addition, USGS will be part of a team conducting analysis of the small streams data to inform future monitoring and implementation of stormwater permits during 2016-17.

Problem - The Stormwater Work Group (SWG) of Puget Sound has recommended a specific permittee-funded plan for monitoring the effects of stormwater management conducted under the Municipal Stormwater Permits in the Puget Sound region. The resulting program is called the Regional Stormwater Monitoring Program (RSMP). Specifically, the RSMP includes status and trends monitoring of water quality and "watershed health" (physical habitat, sediment chemistry, and biological communities) in small streams in the Puget Sound lowlands; and of sediment quality, bacteria, and mussel contaminants in the marine nearshore of Puget Sound. The RSMP has sought out USGS to help implement this first round of small streams and nearshore sediment quality monitoring to assure a successful start to the program, and to draw on USGS expertise to help refine the monitoring for subsequent monitoring rounds.

Objectives - The primary objective of this initial round of RSMP small streams monitoring during 2015 is to collect data at pre-selected sites in wadable streams to establish a "pre-permit" baseline of healthy and impaired Puget Lowland streams. In addition, the USGS will examine the effects of flow alteration at a subset of the RSMP stream sites. The primary objective of this initial round of RSMP nearshore sediment quality monitoring during 2016 is to collect data at pre-selected sites to establish a "pre-permit" baseline of sediment chemistry, quantitatively assess the role natural and anthropogenic factors may play in determining sediment quality, and provide scientifically based modifications or updates to the proposed sampling protocol for future sampling activities.

Relevance and Benefits - Completion of the proposed work will provide the USGS with additional instream flow, water quality, biological, and habitat information on small streams and in the marine nearshore in mixed land-use settings that will assist in understanding and describing the Nation's water resources. This study will provide Municipal Stormwater Permitees throughout Puget Sound with documentation of flow, water and sediment quality, biological, and habitat conditions at the beginning of the Regional Stormwater Monitoring Program that will serve as a baseline for monitoring trends in the status of these conditions over multiple 5-year permit cycles. This information will also help the permitees, along with EPA and the Department of Ecology, evaluate the combined effectiveness of current and future stormwater management activities on protecting or improving stream health on a regional scale. The permitees will benefit by having the USGS serve as an unbiased third party with extensive technical expertise in the collection and analysis of water quality, biological, and habitat data. In addition to providing consistent and reproducible data, USGS expertise will be used to suggest any refinements that may improve this and similar regional-scale stormwater monitoring programs. The public will gain an improved understanding of the health of their local streams and nearshore waters and will be provided information on the benefits that are expected to result from the costs of implementing municipal stormwater permits.

Approach - Monthly water-quality monitoring at 36 stream sites will include standard field measurements, chloride, nutrients, fecal coliform, turbidity, dissolved organic carbon, selected metals and PAHs. One-time watershed health monitoring at 57 sites will include physical habitat, bed-sediment chemistry (selected metals, PAHs, pesticides, phthalates, PCBs, PBDEs, and hormone disrupting chemicals) and biological community (macroinvertebrates and periphyton) characterization.

The USGS will coordinate and collaborate with State and local agencies in the collection of marine sediments from nearshore environments at 40 sites within the Puget Sound during the summer of 2016. Samples will be analyzed in the field for physical/environmental characteristics including sample penetration depth, sediment temperature, salinity of the overlying water, and sediment texture, color, and odor; and chemical analyses in a laboratory will include grain size, organic carbon and the same analyte list used for stream sediments (selected metals, PAHs, pesticides, phthalates, PCBs, PBDEs, and hormone disrupting chemicals).