Wastewater treatment is something I have a soft spot in my heart for. What’s interesting to me is the amount of perfectly clean, pure, valuable WATER we use to flush ‘away’ our poo – when all is said and done, feces comprises less than 1% of everything flushed into the sewer system. The average person flushes away 15,000 liters of perfectly clean, potable water just to make their toilet work. This creates a major unnecessary burden on our pocketbooks ($5 billion a year?!?!), wastewater treatment facilities, and of course, our freshwater resources.
So the idea of using natural marshes and lagoons to treat wastewater, at a lower cost and with fewer resources, is therefore pretty intriguing to me. I was keen to visit the town of Arcata, California. The town is world renowned for its wastewater treatment system, which it calls a ‘wildlife sanctuary.’ Though the system doesn’t actually reduce water input at the user end, it does put some of this water to good use, and majorly reduces resource costs for treatment.
In 1975 Arcata was in need of a new wastewater treatment plant. The regional Wastewater Authority proposed a $25 million dollar ‘conventional facility’ project. Not surprisingly, citizens objected. In response a professor from the town’s university, Humboldt State, proposed a wetland-dependent treatment system. Their estimated price tag? $5 million. Residents cheered. Today this cost-effective marsh system treats wastewater for the town’s 16,000 residents.
When wastewater reaches the facility, most solids are separated out and composted for use in local parks to improve soil quality. The remaining liquid portion flows through a series of ponds and marshes throughout the sanctuary.
Bacteria, algae, bullrush, and cattails in these ponds treat the water naturally, removing pollutants, and cleaning the water. To the untrained eye, these treatment marshes and ponds look like exactly that – marshes and ponds – and you wouldn’t know that all this work was going on. A large portion of the wastewater is even treated to ‘tertiary levels’ – above and beyond what most treatment plants in the United States are currently equipped to do. Once water has traveled through the marsh and pond gauntlet, it is released into Humboldt Bay, back into the water cycle.
When we first arrived at Arcata Marsh we noticed a full parking lot – not usual for a wastewater treatment facility. But the marsh has 5 miles of walking and biking paths. We saw several bird watchers stuck to their binoculars, hoping to catch glimpses of the area’s rare pelicans, or the other 270 species of birds present in the marsh. The brochure boasts of river otters, tree frogs, wrens, sparrows, warblers, mallards, fish, herons, falcons, harriers, hawks, osprey, bald eagles, and a long list of other wildlife.
We also saw a number of runners on the trails, as well as a group of Jewish men. It was a wonderful late afternoon walk, the perfect way to decompress from a long day of trash blog driving. Who knew wastewater could be so fun?