Performance of a Sewage Stabilization
Pond in a Maritime Climate
JOHN N. WILSON, Biologist
Public Health Service
Portland, Oregon
JAMES H. McDERMOTT, Senior Assistant Sanitary Engineer
Public Health Service, Region II
New York, New York
ALFRED LIVINGSTON III, Senior Chemist
Washington Pollution Control Commission
Olympia, Washington
Sewage stabilization ponds are rapidly gaining acceptance in this country
as a proven means of municipal waste treatment. Histories of the use of
stabilization ponds to treat sewage have appeared in several articles; Caldwell
(4), Fitzgerald and Rohlich (5) and Parker et al (12). Ponds may be utilized
to serve a number of purposes in sewage and waste treatment, but whatever
the function, the unique aspect of ponds is the interaction of algae and bacteria - a symbiotic relationship (8) - in which algae by photosynthesis provide
oxygen for maintaining aerobic decomposition by bacteria.
Heretofore, most of the performance records of sewage ponds have referred to areas of moderate rainfall, high evaporation and solar radiation as exemplified by Towne et al (15) in studies of ponds in North Dakota. Would
they work in the Pacific Northwest with its long rainy season? This was the
prime question that stimulated the project about to be described.
The newly constructed sewage stabilization pond at Long Beach, Washington, afforded an excellent opportunity for study of performance in a
maritime climate. There were a number ofjreasons for this, as will be shown,
but among the most important was that it was one of the first to be placed in
operation in the area.
SELECTION CRITERIA
Long Beach is situated in the midst of one of the Pacific Northwest's most
unique resort areas. The attractiveness ofthe 20-mile-long peninsula shown
in Figure 1 with its superb sand beach, its cool climate, and abundant shellfish resources has caused an influx of thousands of tourists during the summer
season. While the resident population of Long Beach is no more than one
thousand,  upwards of 30,000 may be expected over a busy summer weekend.
The mounting problem of sewage disposal which stemmed from these extremely variable populations was vexing to the city officials for a number of
reasons. For years, septic tanks were utilized throughout the town in the belief that by avoiding |ewer collection, the problem of an ocean outfall would
be obviated. However, the occurrence of numerous septic tank failures with
resulting unsanitary conditions in close proximity to the main business district,
contamination of the bathing beach on Jacobsen Lake Figure 2, some one-half
mile to the north and east from the main business district, allegedly from
septic tanks prompted an engineering study in 1955 to seek a remedy.
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