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A Marine Recovery Area (MRA) was established to protect especially sensitive marine waters from pollution from poorly functioning or failing on-site sewage systems (OSS). A 2006 state law (RCW 70.118A) required Puget Sound counties (including King County) to designate MRAs where shellfish growing areas are closed due to bacterial pollution (or if closure is likely), or where bacteria or nitrogen are seriously affecting water quality.

Why an MRA formed

The MRA in King County was established because parts of Vashon-Maury Island are currently closed for commercial and recreational shellfish gathering. Human waste, most likely from poorly functioning or failing on-site sewage systems (OSS), contributes to the closure of shellfish areas, according to Washington State Department of Health Shellfish Program sanitary surveys.

The MRA encompasses sections of Quartermaster Harbor, Klahanie, Dolphin Point, Glen Acres, Hawthorne, and Summerhurst. See detailed maps of the Marine Recovery Area below.

Maps showing individual parcels with color coding to identify the level of information available in the Public Health — Seattle & King County records for each On-Site Sewage system. The maps are color-coded to show the status of OSS for each property as follows:
...... Vacant or limited use lot
  No septic system record (permit, file, etc.) and no record of O&M inspection
  Septic system record (permit, file, etc.) but no record of current O&M inspection
  Septic system record (permit, file, etc.) and O&M inspection completed on schedule

Vashon-Maury Island Marine Recovery Area Island wide index map

Quartermaster Harbor Maps from north to south

East Passage maps from north to south

How living in the MRA affects you

On-Site Sewage System owners in the MRA must have annual operation and maintenance (O&M) inspections performed by a King County licensed On-Site System Maintainer.

What to expect during an inspection

The annual O&M inspection differs from having your on-site sewage system tank pumped. Pumping a sewage tank is removal of liquid and waste done by a King County certified liquid waste pumper/haulers.

What to expect when the septic tank needs pumping

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