The question Russian Riverkeeper is asked most is: “Is it safe to swim in the river?” The simple answer is yes for most people most of the time. Hundreds of thousands of residents and visitors swim in the Russian River each summer without any problems, although we have heard of people reporting illness after swimming in the River. Data from local clinics and hospitals, where accurate diagnosis can be determined, do not indicate widespread or significant illness linked to swimming in the Russian River.

Blue-Green Algae

In recent years, attention has been drawn to the presence of Blue-Green Algae, or Cyanobacteria, at unsafe, high levels in the Russian River waters in late summer. Algae is a normal inhabitant of our river, but when we get high temperatures and elevated nutrient concentrations, the algae grows more rapidly than usual, creating mats or blooms. Most algae is harmless, but some species of blue-green algae can produce toxins which create health effects for humans and animals. We must be especially careful to keep small children and dogs away from these types of blue-green algae blooms. Up-to-date test results and more information can be found at the County of Sonoma Department of Health Services.


The principal concern for human safety in fresh water rivers is bacteria pollution but it is a very complex topic as you will read in the paragraph below. Every summer popular swimming beaches are monitored for bacteria. When fecal indicator bacteria levels exceed recommended levels, warning signs are posted at the beach. Beach monitoring results are posted by the Sonoma County Department of Health Services weekly and results can be found here.

Our bodies have more bacteria cells than human cells, we would not survive more than a few days or hours if we removed all bacteria from our bodies. Bacteria help us digest our food, regulate body systems and actually protect us from disease and more harmful bacteria. There are millions of species of bacteria and yes some are bad and can cause illness. When rivers are tested for bacteria to protect swimmers, they are testing for what we call coliform bacteria that is normally found in the gut of mammals. This bacteria itself is not harmful but is used to potentially indicate the presence of other harmful bacteria associated with digestive systems in mammals. When these “indicator” bacteria levels go up there is a chance that it could indicate the presence of harmful bacteria that would generally lead to gastrointestinal illness (stomach bug), ear infections or sinus infections.

That said when bacteria levels are high we often get no reports of illness from local clinics and hospitals and sometimes when indicator bacteria levels are low we sometimes hear that people are getting sick. Some of this has to do with the great degree of difference in individual immune systems, whether they ingest water or not and other factors such as whether they might have food borne sickness or other illness that contributed. We urge people to use common sense, if you think you have a compromised immune system avoiding swimming when warnings are posted or avoiding natural waterways all together might be warranted. Our Riverkeeper, Don McEnhill, has swam in the river his whole life with no illness – even back when sewage dumping occurred all summer in the old days – and since his kids were two years old they have been in the river every summer with no ill effects yet. At the same time people who have been on rivers their entire lives get ear infections every time they go swimming in a river or go to the Ocean.

Visitors with question about the status of the Russian River can call the county beach hotline at (707) 565-6552.

What’s that foam in the water?

Russian Riverkeeper often gets calls about foam in the River, which can be natural or pollution. Here’s a handy guide:

What causes foam to appear on rivers, lakes and streams?

  • As with most liquids, water molecules are normally attracted to each other. This attraction creates tension at the surface of the water, often referred to as a thin “skin,” which allows some insects to glide across it.
  • When leaves, twigs or other organic substances fall into water and begin decaying, they release compounds known as surfactants.
  • This interaction breaks the surface tension, which in turn allows air to more easily mix with water and creates bubbles. These bubbles congregate as natural foam.
  • However, not all foam is natural. Certain man-made products, including detergents, can cause foam that is similar in appearance, but may be harmful to fish and other aquatic life.

When am I most likely to see natural foam on a water body?

  • On a windy day, because foam occurs when air mixes with water to form bubbles.
  • During the fall when trees drop their leaves and aquatic plants begin to die back and decompose.
  • You may also see foam throughout the spring as plants lose their buds.
  • When the outdoor temperature rises, because heat accelerates plant decay, which releases the organic substances that contribute to foam.
  • During soil erosion events or from human activities, such as gravel washing.

Is foam harmful?

  • Foam is usually harmless. In fact, only 1 percent of the foam you see on a water body is the actual foaming agent; the rest is air and water.
  • However, excess foam is sometimes the result of too much phosphorus in the water.
  • Although phosphorus in an important plant nutrient, it is not found abundantly in nature and too much of it is indicative of pollution from human activities.
  • Excessive phosphorous can result in nuisance algae blooms, fish kills due to low dissolved oxygen from decomposition processes, and irregularities with the water’s taste and odor.

How can I tell what kind of foam it is?

  • Although it’s difficult to know for sure, foam from various sources can have different characteristics.

Natural foam usually:

  • appears as light tan or brown in color, but may be white
  • smells earthy, fishy or has fresh cut grass odor
  • can occur over large areas and accumulate in large amounts, especially on windward shores, in coves and eddies
  • dissipates fairly quickly, except when agitated (as in high wind conditions)

Unnatural foam from human activity usually:

  • appears white in color
  • gives off a fragrant, perfumed or soapy odor
  • usually occurs over small area, localized near source of discharge

What should I do if I suspect a waterbody’s foam is the result of a chemical release or spill?

If you suspect foam to be from unnatural causes, call the North Coast Regional Water Quality Control Board at 707-576-2220. If you see dead or injured wildlife or fish you think resulted from a spill call California Department of Fish and Wildlife at 888-334-2258

Polluted urban run-off

One of the greatest threats to water quality in the Russian River and most of the United States is polluted urban run-off. Urban areas have high amounts of what we call impervious surfaces such as driveways, parking lots, roads, rooftops that are hardened and do not absorb water. During dry periods potential pollutants such as dirt, leaves and lawn clippings, oil, pesticides, fertilizers, heavy metals from vehicle use and trash build up on the impervious surfaces that are usually connected through downspouts from rooftops, gutters from roads and parking lots directly to storm drains that lead directly to our creeks and river. When it rains all the pollutants are corralled by curbs and gutters and sent to our local creeks and the Russian River through the storm drains that have no filters to remove these pollutants.

Learn How your Landscaping Can Act Like a Sponge and Keep the Russian River Clean – State Waterboard video

There are two main strategies for reducing this pollution source in a sustainable manner. The first is called Source Control, which involves cleaning up the streets and parking lots with street sweepers and vacuum trucks and simple acts like picking up trash or sweeping up dirt and leaves before it rains. The other strategy is to change the way water flows off the hardened or impervious surfaces using what we call Low Impact Development that slows down, spreads out and sinks urban run-off into specially designed landscape areas such as rain gardens or bioswales.

The goal of Low Impact Development or LID is to not use curbs and gutters to direct water to storm drain inlets but to route water to landscaped areas where it can be cleaned up naturally. Rain gardens and bioswales are designed with highly composted soil layers and certain plants that work together to capture pollutants before they go to creeks or to groundwater. The composted soils have bacteria and microbes that break down oil and grease and the soils also capture heavy metal particle and fertilizers by absorption. The plants in these areas take up many of these pollutants when they grow. Solids like dirt, leaves and grass clippings are incorporated into the soil and items like trash are physically captured so it can be picked up. The other benefit of rain gardens and bioswales is that they can reduce the amount of water that speeds to our creeks due to the hardened impervious surfaces which can reduce urban flooding in heavy downpours.

This Rain Garden at Healdsburg High School captures and filters stormwater run-off.

Rural and agricultural water quality

Outside of urban areas rural roads and agricultural activities can generate pollutants such as dirt or sediment that wash into our creeks and river when it rains. Many old rural roads, old logging roads and many roads servicing agriculture where built years ago before techniques were developed to reduce the sediment release from dirt roads. Currently many property owners are re-building their dirt roads to reduce this problem by changing the slope of roads and upgrading road culverts that drain water. Another strategy is to move roads further from stream areas since roads right next to streams are difficult to fix and reduce the sediment release due to being so close to a stream. By moving roads further away when the opportunity is present it can greatly reduce water quality problems.

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