By disposing of boat sewage at pumpouts or dump stations, you will be helping improve water quality for everyone.
Many of Washington's prime shellfish beds have been affected by elevated levels of raw sewage at one time or another. Of the 145 acres of public recreational shellfish beds, 50 percent have been closed or downgraded. More than 46,000 acres of key shellfish growing areas in Washington have been closed or had harvesting restricted due to various sources of contamination since 1981.
Boat sewage introduces disease-carrying bacteria and viruses into the water. Raw or poorly treated sewage can spread disease, contaminate shellfish beds and lower oxygen levels in water. Waterborne diseases including hepatitis, typhoid and cholera can be transmitted by shellfish.
Water in shellfish areas is regularly tested by County Health Departments to determine if harvested shellfish will be safe to eat. Test results are expressed as the number of bacteria per 100 milliliters of water. Shellfish beds are closed when the coliform count reaches 14 per 100 milliliters of water. Public beaches are closed to swimmers when the coliform count reaches 200 per 100 milliliters of water.
Areas most likely to be affected by sewage contamination are as follows:
Sheltered waters with slow circulation rates
Waters with significant recreational uses
Areas set aside for shellfish habitats such as those in coastal zone programs
Areas designated by the Environmental Protection Agency as no discharge zones.