History of Arcata's Wastewater Treatment
Historical Treatment Regional Plant Wetlands & Marshes References

Beginnings of the Arcata Wastewater Treatment Plant

In 1933 the sewage system of Arcata was a primitive 400 foot pipe emptying into a 500 foot ditch just east of what is now known as Butcher's Mouth Slough. The sewage was later found to be contaminating the oyster beds in the Arcata trestle area, which could have been the cause of a paratyphoid epidemis in Berkeley where the oysters were sold (Eisenberg 1990). Various new arrangements were experimented with, a design that was both efficient and accepted by the public was not found until years later.

Arcata's first water treatment in 1949 plant was only primary treatment, releasing un-chlorinated effluent into the Arcata Bay. The effluent carried suspended solids, Biochemical Oxygen Demand (BOD) and possible pathogens, like those that caused the epidemic years earlier in Berkeley (FOAM 2008). In 1957, 55 acres of oxidation ponds were added (Figure 3), putting the water though a secondary treatment process. Chlorination was added to the treatment process in 1966 and dechlorination in 1975 (EcoTipping Points, 2008).

Oxidation Ponds created in 1957 as secondary treatment of Arcata's wastewater

Figure 3: Oxidation Ponds created in 1957 as secondary treatment of Arcata's wastewater. Dustin Poppendieck