Monthly Archives: September 2018

Toxic algal blooms found across the country – What you need to know

by: Angela Danovi, Arkansas Regional Project Manager, Ozarks Water Watch

Over the past several weeks and past few months, there seems to be an explosion of stories concerning toxic algal blooms degrading lakes across the country. In 2017, 169 Algal blooms in 40 states were headlined in the U.S.  In 1999, the upper James River arm of Table Rock Lake suffered a major algal bloom (photo below).

It is unknown if the bloom was toxic blue-green algae, but if swift measures had not been put in place, it is likely we would be experiencing blue-green outbreaks today. In response, water quality groups in Missouri, such as Table Rock Lake Water Quality (now merged with Ozarks Water Watch), came together with the Department of Natural Resources and the Missouri Clean Water Commission to place phosphorous limits of 0.5 ppm on wastewater treatment plants located within the Table Rock Lake watershed. Since then, there have been no major algal blooms on Table Rock Lake.

Algal blooms can blanket vast expanses of a lake with what looks like thick, sickly green split-pea soup. Blooms are normally triggered by nutrient pollution from agriculture sources, septic systems, sub-standard sewage treatment plants and stormwater runoff, and are exacerbated by warming temperatures and intense rains.

Algal blooms can generally be thought of in two categories: harmful algal blooms or nuisance algal blooms.  Nuisance algal blooms or algae outbreaks may be used to describe macroalgae, which are large visible free floating, or microalgae which require a microscope to see but in mass are highly visible.  Cyanobacterial harmful algal blooms (cyanoHABs) in inland waters severally impact human health, pets, wildlife, aquatic ecosystems, and the economy.  Toxic blue-green algae is technically not algae, but photosynthetic single-celled organisms called cyanobacteria. The toxin produced in blue-green algae is called microcystin.

Slide presented by the Arkansas Harmful Algal Bloom (HABs) Workgroup – December 5, 2017 (

In a December 2017 presentation to the Arkansas Harmful Algal Bloom workgroup, several points of information were presented about HABs:

  • HABs are becoming more frequent and predictable, especially in nutrient enriched water bodies.
  • 2.5 million acres (nationally) of lakes, reservoirs, and ponds have poor water quality due to nitrogen and phosphorus pollution.
  • Some algal blooms can produce toxic compounds (cyanotoxins) at levels of concern for human health and the environment
  • When HABs are present near drinking water intakes, cyanotoxins can enter the drinking water utility’s supply, putting the local population at risk.
  • Toxins from HABs are also harmful and can cause death to pets and livestock
  • HABs also can pose a risk for swimming and other recreational activities on or in the water
  • EPA estimates between 30 and 48 million people use drinking water from lakes and reservoirs that may be vulnerable to cyanotoxin contamination.
  • HAB occurrences have diverse and far reaching economic impacts, not just drinking water, but also on tourism and recreation, real estate values, commercial fishing, and recreational businesses.
  • Nutrient enrichment and the resulting HABs are one of our most widespread, costly, and challenging environmental problems today.

Due to the increasing occurrences of harmful algal blooms, several action steps have been taken in Arkansas to study and better understand the issue, document algae blooms of concern,  and to develop proactive steps to protect water quality and the people who use the water.  In 2015, the Arkansas HABs working group was formed and includes members from state agencies, drinking water utilities, university research groups, and other interested stakeholders. The working group aims to: develop a plan for statewide assessment of risks to public health from cyanotoxins; provide guidance on water sampling, testing, and protocols for toxins; and recommend strategies to reduce and prevent future HABs.


In May of this year, Beaver Water District deployed new monitoring equipment in Hickory Flats Cove on the War Eagle arm of Beaver Lake as part of a research program to help determine causes of algae blooms and sources of nutrients in Beaver Lake.  The location was selected because of the high algae concentrations that are measured in the cove each year.

Vertical profile sampler on Beaver Lake deployed by Beaver Water District in 2018.


How you can help protect our waters against Algae Blooms

Snapshot of the ADEQ Harmful Algae Bloom Complaint Form

ADEQ has also launched online complaint forms for Harmful Algae Blooms and Nuisance Algae Blooms.  Through the complaint form, anyone can submit multiple photos, provide location information, and site descriptions if you observe an algal bloom in Arkansas.  Even if you are unsure of what type of algal bloom you are seeing, take photos, and submit a complaint so that it can be further investigated.

Click here to submit a nuisance algae complaint

Click here to submit a harmful algae bloom complaint


Fortunately, for the most part, the Ozarks area has been spared toxic algal blooms. Just a few years ago, Table Rock Lake experienced the clearest water in decades (photo above). Financial support from governmental agencies, businesses, and the public to organizations like Ozarks Water Watch are vital not only to help us continue to function, but to ensure our staff and resources are around for years to come to provide education, outreach, and projects that better our community by keeping our Ozarks waters clean, clear, and safe.


More Information:

Arkansas Harmful Algal Bloom (HABs) Workgroup, December 5, 2017 –

Lakes Presenting Risk for Exposure to Harmful Algal Toxins

National Oceanic and Atmospheric Administration. National Ocean Service – Harmful Algal Blooms: Simple Plants With Toxic Implications

Blue-green Algae and Beaver Lake Factsheet by Beaver Water District