Marine Water Quality

Marine Environment

About this indicator:King County's Marine Water Quality Index includes information about the conditions of marine waters. Our weighting system for the marine environment water quality applies 75 percent to eutrophication and 25 percent to fecal bacteria.

Status: While, in general, the quality of open waters in Puget Sound is good, marine water quality conditions in certain areas of King County show evidence of degradation. Waters that are in protected areas without much current are of concern, including Elliot Bay and Quartermaster Harbor.

Influencing factors: Storm water carrying nutrients from septic systems, chemicals from motor vehicles and phosphorus from fertilizers degrade marine water quality and reduce oxygen levels for the animals that live and depend on Puget Sound habitats.

What you can do:

• Properly dispose of harmful chemicals, including unused pharmaceuticals and latex paints.
• Maintain, repair, or replace failing private septic systems.
• Minimize the use of fertilizers and pesticides by practicing natural yard care.
• Wash your car on the grass or gravel instead of on the street or driveway, or take it to a car wash.

More information about King County's Freshwater Lakes and Streams is available by continuing below for these measures:

• Eutrophication
• Fecal Bacteria in Marine Waters (ambient and outfall)

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Eutrophication

	Marine Eutrophication 2007 Findings

About this indicator: King County conducts monthly water quality monitoring at 14 offshore locations in Puget Sound. Offshore marine waters in King County are monitored for temperature, salinity, density, dissolved oxygen, nutrients, chlorophyll and fecal coliform bacteria. These variables can be used to assess eutrophication, (the process by which dissolved oxygen concentrations are depressed due to algae growth primarily caused by nutrients), sewage waste (fecal coliform, ammonia), food availability to secondary producers (chlorophyll), and marine water habitat quality (temperature, salinity).

Status: 2007 findings indicate that the water quality at one of the stations sampled (Elliott Bay) is at a level of Moderate Concern. Additionally, the water quality at two of the stations sampled (Inner and Outer Quartermaster Harbor) are at levels of High Concern.

The percentage of stations of Moderate or High Concern is 21.4%, the highest level since 2000. This increase in the proportion of stations with Moderate or High Concern designations is mainly due to the addition of the two Quartermaster Harbor stations in 2007.

Influencing factors: Vertical water density patterns can be indicators of an area's potential sensitivity to developing low dissolved oxygen conditions. Low oxygen conditions are harmful to fish and other aquatic life and may occur as a result of the natural flow of low oxygenated Pacific Ocean water into the deep main basin of Puget Sound, in addition to processes such as eutrophication. Persistently low nitrate concentrations in surface water can indicate a potential sensitivity to nutrient-rich input such as stormwater runoff, industrial waste discharges, septic systems, and flow from rivers. Ammonia can be found at elevated concentrations as a byproduct of sewage, agricultural practices, and fertilizer use in urban areas.

Existing DNRP response: DNRP will continue to operate its wastewater treatment plants and conveyance system effectively to maintain low levels of nutrients discharged into marine waters. Nutrient levels are also addressed by the agency through storm water control management practices. Additionally, DNRP will continue to play an active role in the recently formed Puget Sound Partnership toward improving water quality throughout the entire Puget Sound.

Priority new actions: Stratification intensity and its persistence is beyond King County's influence, but should be monitored as it is an important indicator of areas sensitive to possible water quality problems. Dissolved oxygen levels in Quartermaster Harbor will be closely monitored.

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Fecal Bacteria in Marine Environment

About this indicator: The presence of fecal bacteria in water bodies indicates contamination with the fecal material of humans, birds or other warm-blooded animals. Although these bacteria are usually not harmful, they often occur with other disease-causing pathogens, and their presence at high levels indicates an increased possibility that people might get sick if they come into contact with the water.

This standard addresses water quality requirements for protecting swimming, SCUBA diving and other recreational uses. For marine surface waters, the current fecal coliform standard is a geometric mean of 14 colony forming units /100ml.

King County conducts monthly water quality monitoring at 13 offshore locations in Puget Sound. Offshore monitoring sites are divided into two categories, ambient and outfall sites. Ambient sites are chosen to reflect general, or ambient, environmental conditions, while outfall sites are located at King County wastewater treatment plant outfalls and county-operated combined sewer overflow outfalls. Monitoring stations in Salmon Bay and Fauntleroy Cove were added in 2007. Data from those stations will be reflected in 2008 results.

Status: Fecal bacteria are not a concern in parts of the Puget Sound that surround King County. All ambient and outfall sites met the fecal coliform bacteria geometric mean standard in 2007.

Influencing factors: Non-point source pollution is the major cause of marine water contamination. Fecal coliform can enter Puget Sound from domestic animals, wildlife, storm water runoff, wastewater discharges and failing septic systems.

Existing DNRP response: DNRP will continue to manage its wastewater treatment plants and conveyance system effectively. The county is working with the Puget Sound Partnership effort toward protecting and restoring the health of marine waters.

Priority new actions: No changes in the monitoring program are planned for 2008.

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