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Water quality is an issue throughout the world. The very meaning of the term varies according to perspective. Iowa has its controversies regarding one issue of water quality that has made the papers recently–nitrates in the surface waters.

Nitrates in surface waters are most likely from fertilizer runoff from farm fields, but can include other sources. If they are in drinking water, it can be dangerous for infants and nursing mothers. For Lake Panorama residents, nitrates are not a concern as something physically harmful, because the LPA water supply does not come from surface water. However nitrates do affect the lake as they provide food sources for blue-green algae, which are a potential problem for water quality for those that use the lake for water contact recreation.

Blue-green algae (cyanobacteria) is a primitive organism that reproduces rapidly in hot, quiet waters where nutrients (such as nitrates) are available. Lake Panorama, a reservoir on the Middle Raccoon River, does have high nutrient levels after heavy runoff periods. Present conditions are possibly producing what is called an algal bloom…a heavy fast growth of algae that can give the lake a green color.  If the bloom is particularly large…it will turn the water in some areas to the appearance of paint. (An algae bloom is not necessarily uniformly distributed in a large lake.)

Blue-green algae can be dangerous because there are times that some of the varieties of the organism can produce toxins which can be everything from simply irritants to skin and lips, to poisonous for small creatures and small children. The problem is that one cannot see the toxins if they are present. In several years testing here, there was one week when toxin levels taken from the most severely affected branch of the lake, were above safe levels. Since conditions can vary significantly from one part of the lake to the other in our relatively large lake, it would take hundreds of samples to determine if there were issues everywhere. Instead, we have personnel look for the heaviest infestations, when they occur, and sample those locations to see if toxins are present and at what concentration.If the samples show concentrations over levels deemed dangerous, notification to the Lake Panorama public will take place.

Here’s some important tips about blue green algae:

  1. Don’t swim or ski in waters that are heavily colored or with a layer of scum.
  2. Thoroughly wash after water contact recreation–including thorough rinsing of bathing suits and accessories.
  3. Never allow small children or pets to play in or consume heavily colored water. The same goes for people with poor immune systems. Don’t let pets lick themselves after going in such waters.
  4. These documents can give much better and complete information:  FAQ Blue Green Algae,   FACTS about Algae

The other primary water quality concern (regarding health for water contact recreation) is e-coli bacteria. This bacteria is an indicator of contamination by human and animal waste. Potential sources would be runoff from pastures, livestock feedyards, wildlife, poor septic systems, or leaks or overflow from public wastewater treatment plants. E-coli can cause stomach ailments and worse, including in cases of food contamination, serious illness and rarely even death. The effects on individuals, of course, depend on their state of health, their immune systems and other factors.

The LPA uses State recommended sampling techniques to sample water at all three LPA beaches every Tuesday during the swimming season. Samples are sent to the Iowa Hygienic Lab testing facility in Ankeny and results are usually available on Thursday. Levels of 235 or more colonies of bacteria per sample are considered dangerous to health and if test results are 235 or higher beaches are posted “swimming not recommended.” Interestingly, results can wildly differ from week to week due to one of two things–heavy inflow due to heavy rain and wildlife contamination. Heavy inflow washes bacteria from all kinds of potential sources into the lake. Wildlife, if concentrated in an area, such as geese, can also create high numbers due to their droppings.

In the case of either blue-green algae or e-coli, the LPA will be testing for both issues the rest of the summer. (we only test for blue green algae toxins when conditions are ripe for an algal bloom, which is possibly beginning.) These results will be available either at or by logging in and subscribing to the weekly water quality ebulletin at the LPA website by doing the following: Log in. Click on “my profile.” Click on the “subcriptions” tab in the upper part of the profile. Select “Beach Water Quality” ebulletin and scroll down and click “save changes to make the subscription final. Ebulletins for water quality will be sent weekly for test results and, in the case of potential problems, whenever the problem is discovered.

Members should be careful to not be misled by the test readings and interpret them too closely. The numbers are important, but can have too much read into them. Here are some reasons:

  1. The tests are taken on Tuesday mornings and only indicate the concentrations of bacteria at that particular time on that day in that place.
  2. Wind and sunshine can change readings considerably as afternoon mixing of quiet, wildlife contaminated waters from early morning sampling (and overnight goose activity) can reduce concentrations considerably. Ultraviolet light in sunlight actually kills e-coli and wind and sunlight can gradually reduce readings over the entire lake.
  3. Even good tests can be misleading as there could be many other organisms present in the water that aren’t tested for. Anyone who has taken a fresh water biology class will recognize how complicated and how much variety there is in fresh water organisms. E-coli in itself can cause severe illness, but other organisms can too, and many are much too rare to effectively test for. In short, be careful all the time and chances of any illness produced by water contact will be reduced.
  4. Personal health, hygienic habits, and experience can provide much resistance and protection from the effect of exposure–washing thoroughly prior to eating after lake recreation is just common sense. Open sores or cuts are open invitations for lake organisms to enter a human body.
  5. Examples abound…Test results this week gave a very high bacteria count at Boulder Beach, likely caused by geese. Yet, just 3,000 feet away in the same lake, counts were barely found at Shady Beach. Many other areas of the lake may be perfectly fine and bacteria counts highly localized until winds, waves and sunlight work their magic.

In conclusion–water quality, in our case the quality of lake water for water contact recreation, is an important issue. Be aware of the possibilities. Know that murky waters (silty) shelter e-coli bacteria and increase the time it takes for sunlight to help purify bacteria laden waters. Know that heavily colored waters harbor the potential of toxin contamination. Keep track of testing reports and avoid areas where wildlife sign is present. It’s mostly common sense, but it takes some solid knowledge to act appropriately.


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