Enemies of the Lake
Trying to predict what any summer lake season will bring is a fool’s game at best. I wish I had an algorithm that would do the trick, but the variables are just too, well, variable to try any kind of reasonable simulation. Our biggest two enemies are nutrient levels (primarily Phosphorous) and high-water temperatures. Last year we had plenty of heat, and, judging from the early warm weather, we can expect more of the same this year. Our background P levels seem to stay relatively stable most of the year, but they are definitely high enough to support algal and weed growth. The deposit of all that ash from past fire seasons didn’t help either, as ash is very rich in nutrient content. Although it is impossible to know how much the ash contributed to our second season blue green algae bloom, it certainly could have been that famous last straw. Blue green algae are a bit of a misnomer as it is not actually algae but Cyanobacteria, and some strains can be toxic. Fortunately, our situations the past two seasons were not toxic, but it does get your attention. From the trivia department, Cyanobacteria is believed to be one of the earliest forms of life on earth.
Our testing program got underway on May 2, and E. coli levels at the beach lines are being posted on our website. You can access those numbers on either the public or private side of the site. Click on the blue “Lake Condition Reporting” tab and it will take you to our colorized testing map showing all our testing locations and the most recent results. Click on the map and it will give you the actual readings in a spreadsheet format. There are also options for accessing historic data, as well.
Since Meadow Park no longer has a beach, that reporting site has been eliminated. We take samples for E. coli levels twice a week on Mondays and Thursdays. It’s important to remember a few things when using this data to make a decision whether to use the beaches, especially with small children. It takes a minimum of 24 hours after sampling to receive the data, as these samples have to be incubated
overnight before the actual test can be performed. We do our best to get the data on the website by the end of the day following the sampling. Given the sampling schedule and incubation times, these data are anywhere from 24-96 hours old.
Bottom line here is we are always looking in the rear-view mirror when it comes to E. coli postings. The data are still very valuable and allow us to track the trends of anyone sampling point as well as the absolute numbers. The maximum E. coli count considered safe for recreational use is 320 and will show up as red on the website map if we reach or exceed that level. We also use a very conservative self-imposed cautionary level of 100 that will show on the map as yellow. We do not close the beach at this level, but use it as heads up for those who are very concerned or have small children. We will automatically close any beach when we get an E. coli count at or above 320. We do have an algorithm as
to when to reopen the beach based on the current and past two readings. Using this algorithm, it is possible to see a current green dot on the map that still carries the X symbol of a closed beach. The yellow and red beaches will also have physical warning markers on site.
So, chill out and enjoy this beautiful lake season, but remember it’s a lake and not a swimming pool. No reasonable system of testing or monitoring can guarantee the safety of the water at every moment in time, and by using the Lake for recreating, every Member and guest assumes this personal risk. Any fecal matter at the beach lines in our swimming areas should be an alert that the E. coli levels may be elevated and unsafe for small children or those members with high risk levels.
This Monday, we celebrate our nation’s independence from foreign rule and the drive of a group of passionate young men (no women, of course, being the 18th century) to determine their own fate, and that…
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