At the end of May, 192,000 people and 3,000 businesses in Salem, Oregon, were told not to drink the water due to a toxic algae bloom in an upstream reservoir. Testing in the preceding days had shown levels of toxins in the water that made it unsafe for adults and then later just for small children and the infirm. The toxins were cyanotoxins. According to Salem’s Statesman-Journal:
A common bacteria called cyanobacteria sometimes produces a natural poison called cyanotoxins. In mammals, exposure to cyanotoxins can cause allergic reaction and respiratory issues, and cause acute illness, including liver and kidney damage, according to the U.S. Geological Survey. With extreme exposure, symptoms may include organ failure, paralysis and even death.
Salem’s isn’t the only local water supply in Oregon at risk for this type of contamination. Most Oregonians drink surface, rather than ground, water. Taking a tally of water supplies that are vulnerable leads to the realization that these watersheds are hammered by human uses and abuses. Consequently, protecting these water supplies involves getting serious about protecting the watersheds.
A Problematic Reservoir and a Problematic Watershed
As of the end of June this year, four health advisory alerts had been issued this summer for Detroit “Lake” (it is actually an impounded river more accurately called a reservoir) on the North Santiam River. The City of Salem draws its water from the river downstream of the reservoir (Figure 1). Toxic algae blooms routinely occur each summer in Detroit Reservoir. Now they’re getting worse and coming earlier.
Figure 1. Detroit Reservoir is the source of the toxic algae blooms that earlier this summer toxified Salem’s (and Turner’s and Stayton’s and suburbs’) water supply. Source: City of Salem.
Complicating matters for the City of Salem is that the Army Corps of Engineers is planning to drain the Detroit Reservoir for up to two years to improve fish passage and water temperature for migrating salmon and steelhead. Of course, the best thing for salmonids would be to just remove both Detroit Dam and its downstream companion, Big Cliff Dam.
Noted research ecologist and freshwater conservation biologist Chris Frissell says that phosphorous pollution, a driver of toxic algal blooms, is exacerbated by daily reservoir fluctuations (such as at Big Cliff Reservoir just below Detroit Reservoir) and by sediment eroding from clear-cuts and roads throughout the upper North Santiam River watershed. Another driver is nitrogen pollution, which increases after logging. Fire retardants dropped from airplanes onto forest fires don’t help, either.
Historically, Salem has used a sand filter system to treat its drinking water, as the water going into the system was of relatively good quality. Now the city is chlorinating more and experimenting with activated carbon and ozonation. A couple of hundred million dollars may have to be spent to “fix” the problem.
Toxic Algae Blooms: A Chronic and Pervasive Problem
Detroit Reservoir has gotten the most toxic press, but forty-seven bodies of water in Oregon have had at least one toxic algae bloom since 2007 (Table 1), according to the Oregon Health Authority (OHA). In Table 1, I have taken the liberty of correcting the OHA’s misnaming of reservoirs as lakes or ponds. Some of the offensive forty-seven are natural lakes whose water levels are now manipulated for human uses (for example, Odell, Tenmile, South Tenmile, Diamond, Agency, Paulina, and Fish). Others have very dense housing along the “lake” shore (for example, Odell, Blue, and Devils). Many are reservoirs that suffer large shoreline fluctuations caused by the production of hydroelectric power or the delivery of downstream irrigation water. All have watersheds hammered by logging, farming, livestock grazing, housing, and other development.
Many More Oregon Domestic Water Systems at Risk
The list of domestic water systems in Oregon at risk of toxic algae blooms currently numbers forty-one (Table 2) but could go up to nearly one hundred. The Oregon Health Authority has implemented new rules to regularly test for cyanotoxins during the summer, which may affect up to two hundred Oregon water systems. About three hundred water systems in Oregon draw from surface water (Map 1).
Map 1. Oregon subbasins with drinking water intakes. Source: Oregon Department of Environmental Quality.
Portland’s Water Supply: The Successful Battle for Bull Run
After polluting its water supply in what is now the west hills of Portland, the citizens of the Rose City convinced the federal government in 1892 to establish the Bull Run Forest Reserve in the Oregon Cascades near Mount Hood . Today, the 65,280-acre watershed is 96 percent federally owned, with the City of Portland owning the rest. In 2001, Congress increased protection for the watershed, now known as the Bull Run Watershed Management Unit (Map 2). Public entry is limited, as is roading and logging in the watershed.
The city has built two reservoirs on the Bull Run River. Because the watershed is now generally protected from logging and roading, toxic algae blooms are not an issue for the one quarter of Oregonians who rely on Bull Run water (in a far greater area than just Portland).
Map 2. Established by an act of Congress in 2001, the Bull Run Watershed Management Unit is 96 percent national forest (with a little Bureau of Land Management acreage) and 4 percent owned by the City of Portland. A land exchange is under way to facilitate better management by consolidating the city’s lands along the two reservoirs and the Forest Service’s lands elsewhere. Source: City of Portland.
It’s the Watershed, Stupid
Alas, a full-on Bull Run solution is not possible for every other municipal water supply in Oregon, but more could be done.
· More public land. If the land in a municipal watershed is publicly owned, it is—or at least could be—managed better than private land. Surface water suppliers should increase their rates to allow them to purchase private lands so their watersheds can be better protected. It’s generally a good idea for a public entity other than the local water provider to own the lands in the watershed, as it has too often been the case (Corvallis and Seattle come immediately to mind) that the municipal utility has logged its own lands to generate operating revenue and avoid raising rates—a strategy that is politically popular in the short term but foolish in the long term.
· More protection of public land. Several Oregon municipalities (including but not limited to Ashland, Baker City, Bend, Corvallis, La Grande, Medford, and The Dalles) draw their water from surface sources on lands within the National Forest System. While some protection is afforded such national forest municipal watersheds, these protections could be greater and stronger.
· More beavers. Water quantity and quality could both be dramatically increased by restoring beavers broadly across the landscape. (See my Public Lands Blog posts “Leave It to Beavers (Part 1)” and “Leave It to Beavers (Part 2).”
· Less logging. Even with stream buffers, clear-cutting and other logging raise water temperatures. Intensive timber management on private timberlands can mean the application of fertilizers, the runoff of which can increase algal blooms (not to mention the spraying of toxic pesticides on timber plantations that end up in our drinking water supplies).
· Less roading. Roads harm water quality. Unnecessary roads should be decommissioned and necessary roads improved to make them more hydrologically invisible. Such is good for humans who drink water as well as for fish and wildlife.
· More treatment. There’s no way around it. Water users are going to have to pay more so the water they drink doesn’t make them sick or even kill them.
· Tactical withdrawal .It would behoove certain municipal water providers to buy out rural residential homes with septic systems located near streams.
· Less climate change. The warmer the climate, the warmer the water and the more toxic the algae. Yet another reason to move rapidly to a post-carbon economy.