Tools for Identifying, Validating, and Correcting Pollution Sources
Water Quality Monitoring and Dye-testing
Includes Establishing Water Quality Monitoring, Ambient Monitoring, Targeted Shoreline Monitoring, Storm/Event Sampling
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Burley Lagoon, Filucy Bay, Rocky Bay Shellfish Protection Districts (SPDs) / Pierce County Pollution Identification and Correction (PIC)
The Pierce County program identifies potential sources of bacteria by sampling all tributaries to the shellfish bays that have a flow greater than one gallon per minute. If levels of fecal colifom bacteria are high (counts of 200 cfu/100 mL or greater), the flow is re-sampled as soon as possible. If the fecal coliform count is again 200 cfu/ 100 mL or greater, the site is generally referred to the Septic Repair Facilitator (SRF) for further investigation. The SRF will send a letter to the property owner, notifying them that a water quality concern has been identified, and asking them to schedule a time for a site visit. The site visit may lead to a dye test of the on-site sewage system (OSS) if the SRF suspects a failing OSS to be the bacteria source. In general, site visits are voluntary. However, if the SRF suspects a problem exists and the bacteria counts are high, an administrative search warrant may be sought by the SRF to require a mandatory inspection.
For dye tests, if the OSS is a gross failure with obvious and continuously surfacing sewage, dye is added to a toilet and a sink and staff wait a period of time to see if dye is visible in the surfacing effluent. If dye is visible, this is considered to be a failing OSS. For less obvious failures, charcoal packets are often used. The charcoal packets are placed in seeps, pipes, streams, or pooled water where surfacing sewage is suspected. If dye is detected in one or more charcoal packets following its addition to a sink and toilet, a sample is collected from the water (seep, pipe, etc.) for fecal coliform analysis. If the fecal coliform count is 200 cfu/100mL or greater and there is a positive dye show using charcoal packets, the OSS is considered to be failing.
Henderson and Nisqually SPDs
Thurston County has an ambient stream monitoring program that includes monthly sampling of the major tributaries to Henderson Inlet and Nisqually Reach. The County may notify a partner agency or sample in other locations if is a sample is considered elevated. There is no targeted sampling to identify problem areas.The OSS Operations & Maintenance (O&M) program inspection requirements are based on potential risk to surface water: Low risk systems must be inspected every three years, conducted by certified OSS professional or by a trained and certified homeowner. Ten percent of systems are verified by county staff. High risk systems must be inspected every three years and pass a dye test every six years. Dye tests are performed by county staff.
Jefferson County Clean Water District (CWD)
Dye testing is performed for OSSs. Jefferson County has found that freshwater water quality shoreline monitoring as well as tracking complaints are the most reliable and efficient ways of finding problem OSSs. Comprehensive stream monitoring is useful in finding OSS issues, although it is energy intensive. Dye tests are used when appropriate to confirm connectivity with local surface waters. At least three shoreline samples within one month are taken to confirm if samples are actually high.
Kitsap Public Health District
Kitsap Health conducts trend (ambient) monitoring of fresh waters and receiving marine waters to determine whether they meet water quality standards and short-term and long-term trends. Shoreline surveys are conducted to protect and restore shellfish beds on a rotating basis and during wet and dry weather seasons. Pollution hotspots are confirmed and investigated through segment monitoring, parcel surveys, and dye testing when necessary.
Oakland Bay CWD
In order to gauge whether OSS inspections are being completed, Mason County does ambient monitoring of a third of the shoreline each year in a three year rotation. This initial survey was important for finding and fixing shoreline pollution problems, but ambient work in the streams and marine water is key to documenting long term success.
Sequim Bay Dungeness Watershed CWD
Investigative/enforcement water sampling has been used to identify pollution sources.
The sampling of ambient freshwater samples changes over time based on available funding. The Clean Water Workgroup (CWWG) makes sampling site recommendations each year. The Jamestown S'Klallam Tribe and other jurisdictions have independent sampling programs. The PIC plan will include baseline monitoring for hot spots for OSSs. The CWD recently did sampling at 9 to 15 stations (the variety is due to occasional problems with access due to water level) in the Marine Recovery Area (MRA) but funding for this effort ended in March.
The County does not actively perform shoreline monitoring. The CWD, however, did some grab samples out of shoreline areas for Microbial Source Tracking (MST) studies.
Skagit County Clean Water Program (CWP) / The Clean Samish Initiative (CSI) / PIC Program
The CSI involves water quality monitoring at 31 sites. Water quality data is used to focus property inspections and restoration activities. Sampling has also included MST and the use of sewage-sniffing dogs is planned.
South Holmes Harbor SPD
Water quality monitoring is ongoing, along with dye-testing.