Officials Issue Cyanobacteria (Blue-green Algae) Warning


Cyanobacteria (Blue-green algae)

Press release from the Department of Health and Human Services:

Local Public and Environmental Health officials are warning recreational users of all bodies of fresh water to avoid contact with cyanobacteria (also known as blue-green algae).

The North Coast Regional Water Quality Control Board in cooperation with the Humboldt County Department of Health & Human Services, Mendocino County Environmental Health and Lake County Public Health Division issued a warning to avoid contact with cyanobacteria and algal blooms. Although commonly referred to as blue-green algae, following the lead of the state, jurisdictions are using the term cyanobacteria as it is not algae, but bacteria.

Typically, cyanobacteria warnings come out between late July and early August, coinciding with low flows and sustained high temperatures in the inland areas which may contribute to cyanobacteria growth in the river.

Human activities have an effect on nutrient and water flows in rivers, streams and lakes. Nutrients found in fertilizers, animal waste and human waste can stimulate blooms. Excessive water diversions can also increase water temperatures and reduce flows. People can take the following measures to prevent algal blooms in our waters:

  • Be conservative with the use of water, fertilizers and pesticides on your lawn, garden or agricultural operation.
  • Avoid nutrient runoff by recycling any “spent” soil by tilling it back into gardens, or protecting it from rainfall.
  • Create shade and filter out nutrients by planting or maintaining native plants around river banks.
  • Inspect and pump out septic systems every three to four years.
  • Prevent surface water runoff from agricultural and livestock areas.
  • Prevent erosion around construction and logging operations.

Cyanobacteria can be present in any fresh water body. It looks like dark green, blue-green, black, orange or brown scum, foam or mats on the riverbed or floating on the water. Warm water and abundant nutrients can cause cyanobacteria to grow more rapidly than usual causing “blooms.” These blooms are termed “harmful algal blooms.” Most cyanobacteria does not affect animals or people, however, a small number of cyanobacteria species are capable of producing toxins that can be harmful to animals and humans. Dogs and children are most likely to be affected because of their smaller body size and tendency to stay in the water for longer periods of time.

The presence of cyanobacteria has been previously confirmed in some water bodies within Humboldt, Mendocino and Lake counties including the South Fork Eel River, Van Duzen River, Trinity River, Clear Lake and Lake Pillsbury. It is difficult to test and monitor the many lakes and miles of our local rivers. Most blooms in California contain harmless green algae, but it is important to stay safe and avoid contact.

Officials recommend the following guidelines for recreational users of freshwater areas:

  • Keep children, pets and livestock from swimming in or drinking water containing algal scums or mats.
  • Adults should also avoid wading and swimming in water containing algal blooms. Try not to swallow or inhale water spray in an algal bloom area.
  • If no algal scums or mats are visible, you should still carefully watch young children and warn them not to swallow any water.
  • Fish should be consumed only after removing the guts and liver and rinsing fillets in tap water.
  • Never drink, cook with or wash dishes with water from rivers, streams or lakes.
  • Get medical attention immediately if you think that you, your pet, or livestock might have been poisoned by cyanobacteria toxins. Be sure to tell the doctor or veterinarian about possible contact with cyanobacteria or algal blooms.
  • Join or support one of the many watershed and river organizations.

To learn more about cyanobacteria and harmful algal blooms, visit the state of California’s website at

To learn more about cyanobacteria and algae on the South Fork Eel River, visit

To report a bloom, e-mail or call 844-729-6466 (toll free). Blooms can also be reported via the “bloomWatch” app which is available for free download on iTunes or Google play.

For information on conditions occurring within Humboldt County, contact the Division of Environmental Health at 707-445-6215 or 800-963-9241. Photos of suspected blooms can also be emailed to



  • thank you northern nights♡

  • I’d love a list we’re supposed to go camping and wanted to take the dogs and kids swimming 🙁

    • Best to pick a different river for sure, the Eel is super low now days. I’m sure the occasional dead bodies in the river help contribute as well, but al least other rivers have more flow than the Eel.

  • Beautiful Country

    Thanks a lot you grower monster jerks! I’m glad you made a million dollars- Not! It’d be cool now if you all just left or died. I would appreciate that.

    • By growers, you mean delta and other so cal mega agriculture farms and corporations growing almonds and other crap in the fricken DESERT RIGHT….? Cause that’s what causes almost all river woos in nor cal. No, pot farms don’t necessarily help. But they are not the root or the entirety of any nor cal river’s biggest issue.

  • Hello, thank you, cows and logging, water pumpers, and overfeeders. Let’s be real, those of you who just picked your favourite pet peeve and gave the rest of history a pass. ^^^^^^

    • Me thinks u need to study the timeline when this algae started to appear buddy. 50+ yrs of logging already happened & our rivers were clean. Good try tho!

    • Beautiful Country

      Gringo- You are wrong and I suspect this is another attempt at distracting or sidelining the conversation, a tactic most devils lettuce sympathizers love to employ. I’ve been here since ’78 and very much love that South Fork Eel in Branscomb to Redway area. Saw lots of logging and cow damage but never had the river killing dogs until much later- after the grows started blowing up. Now the killer algae is in the Van Duzen, the Mad and mainstem Eel. It is a result of warmer water due to slower-moving and shallower water due directly to LESS water. Also higher levels of nutrients in the water. What do you think might do that? DOH!!!

      • You got that right Beautiful Country, I grew up on the South Fork Eel 61′ to 75′, know it like the back of my hand from Piercy to the confluence of the Main Eel. learned how to swim and fished from one end to the other. Never saw anything like this back then. And we would swim every day in the summer, from the crack of dawn until dark.

        One of the most disturbing things I read about, the Mateel has installed two large leach fields in the river bar and flood plain @ Reggae on the River, and dumps thousands and thousands of gallons of greywater/wastewater per day from public showers, personal hygiene and vendors/food prep. WTF…

        I guess they don’t understand “leave no trace”, they must only understand “out of sight, out of mind”!

  • Chemtrails

    • It would be nice if air traffic were curtailed to just the fire fighters. There are days where the air traffic is busier than the freeway. What the hell are they doing up there?

  • I guess Reggae on the River website had it right:

    “The festival weekend allows for a lot of fun in the river, please play at your own risk!”

    Hope they post a warning for people who don’t know…

    • I won’t go to the Eel after reggae, we’re downstream

      • Beautiful Country

        Worked it every year from ’84 until ’96 where I realized it was becoming a special cokefest for special backstage elite and disgusting in many other areas as well. The unreported sexual assaults, the fleecing of the customers, the overselling and over-hyping of the site but yeah it’s always about the $$$ and the bling just cover it with some folksy images and insist that it’s about “community” and “vibes”. It’s a cesspool of deranged humanity posing as “love” while making a killing and killing our river. Wrong on so many levels. Sad.

        • Garth doesnt want to hear that and neither does the mateel,..
          Its a ritual for many, but yes community non profits get to sell fiod such as icecream,and keep their organizations such as volunteer fire departments funded,…
          Other than that, expect to see some debauchery

          • Beautiful Country

            The Manager- Garth is one of the good people left. And yes- the ability of local non-profits to make some money has always been a good thing about Reggae. Unfortunately everybody always wants/needs more $$ and so Reggae got bigger, bigger, bigger and now is a monster. Benbow started out nice but is now going the same direction. Whatever happened to “Small is Beautiful”?! Aren’t there any voices left here for non-explosion? We have prostituted our area and we are losing what made it special in the first place.

    • More like


      but hey Garth doesnt want to,talk about it. Neither do the yupee mateelers.
      Dont make me,come,down and slap you with my dingeling

  • Diane from the water board should come,and clean,up this algae mess.
    They are the ones pretending they care and taxing folks for clean waterways.
    Shes in charge, Dianee Henrioulle sacramento water board (707) 576-2350 tell her to clean this shit up!
    And while your at it find out, how exactly that tier money they are collecting from the growers is keeping the algae out ?? Bringing salmon back??
    We want to see proof here! Assclowns!

  • In the late 1880’s Jeremiah Curtain was riding to Covelo and needed water on a hot August day. Riding down from the hills above he found the main Eel to be a scummy mess of green and couldn’t bring himself to drink the water. (Darn those sheepmen!)
    Water tests at Gville do not show any higher nitrate readings. I wish we could test some streams such as Redwood Creek which is greening up fast, despite the cooler temperatures we are having.
    It is unclear to me how growers are to blame for nutrient runoff at the same time that they are drying up the feeder streams that run into the southfork. ? And in the winter it flushes itself. This year, the southfork has stayed cooler and higher than I can recall going back over twenty years.
    Wish I could ask a biologist some questions… did repeated years of lower flows and drought enhance the proliferation of the algae?

    • tenderHummingbirdneckbbq

      there you have it.
      but the friends of the eel and all the other schmocks like preaching other wise.
      why haven’t they dredged and damed it WITH FISH LADDERS. every year we watch all that water flow out to sea rendering it useless to man. then they push the man made drought on us. un intellectual small minded hill people seem to figure out its good to catch rainwater and to store gods gift in a tank for the dry season, but the state of california can’t seem to catch on to this outlandish idea.

  • A thirty six inch diameter fir tree, measured at a man’s chest height, will suck up 350 gallons a day. And as we know the proliferation of fir since the mid 1800’s is horrendous. Drive a ridgetop and look down every drainage and see who is sucking up the water first! Not to excuse greedy grower water users in the least. Just adding some perspective.

  • Thinking allowed

    The only example I personally have is the grower who left fertilizer bags near edge of the ravine over the creek. Over winter the bags disintegrated and the rains washed the stuff all over the banks. Killed livestock and number of wildlife all spring with every rain. I imagine the continuing influx from the banks simply concentrated as the water level dropped. It does not magically disappear .

  • Well stated, again I have no doubt that many scenes wash bad stuff into the water..far too many. My sidebar point is that Nature is complex, and that there are factors and cycles involved in low waters, and algal bloom besides human use/abuse.
    As I watch Redwood Creek below Briceland and see a low flow and proliferation of algae I know that human take upstream is keeping the water low and creating conditions for the green algae to take off. How much may be attributed to grower runoff is a bigger question mark to me than to others.
    In 1908 the Briceland tan bark plant had to close for lack of water as was reported: “Daily Humboldt Standard, 9/1/1908: Briceland, Aug. 31.–After a long hot spell we are having plenty of north wind now for a change with quite heavy frosts at night. It seems from all signs we will have an early fall. Water was never known so low in this section of the country. Creeks stop running, with hardly any pools at all. Trout are left dry and can be picked up dead by the dozens in the creek bottoms. One can walk all day without a fishing rod and not find a dozen pools large enough to fish in.
    The extracting plant closes down today for want of water.”

  • The biggest diversion of water in my area is from the Trinity River, headed down to the Central Valley. The high water releases that we do get from the dam in the spring are full of sediment that was trapped in the lake (kind of like the sludge you can clean out from the pea trap at the bottom of your sink). This sediment (muck, really) deposits on the gravel bars and river bottom and the algae grows great in it! Not only that, but the water that is taken down to the central valley will never find its way into this watershed, and our water table, again. Some study of google map satellite pics showing clear clean tributary streams and mucked up water coming out of Trinity Lake tells the story.

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