Compare years 2018 to 2019 on Lake Hopatcong – 2018 was Worse - Why Now?

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The following article was written by local lake expert John Kurzman, where he studies the HAB cyanobacteria levels on Lake Hopatcong in 2018 and 2019, and asks the question. Why now, 2018 was worse than 2019.

For those who still are wondering if this algae is a new phenomenon at the lake, whether they would have a reaction, or why the DEP reacted so strongly this year versus last year, please consider that in 2018, the lake had HIGHER levels of the cyanobacteria last year than this year when they issued their dire warnings.

A key difference is that last year, the report that showed how much cyanobacteria the lake had was issued at the END of the season, versus this year they essentially shut down the lake because of it.

So how many people really complained about rashes in 2018? Remember, that's the main issue about the cyanoBACTERIA, unless it turns into the toxin, but we never failed even the NJ standard for the toxins, which is more than twice as strict than the EPA level for 6 year old’s, and 10 times as strict as the EPA level for adults, based on estimations of how much you'd actually drink and how much you weigh, when playing in the water.

Pic1First picture to the right is the Cyanobacteria numbers for July and August 2018. Note how much is over 20K, which did not affect beaches or recreation in 2018, but currently lower numbers are still even keeping some beaches closed!

I got this data by adding together the cyanobacteria cell counts from the 2018 reports, similar to how those reports also summarize the overall cyanobacteria data. The original reports are right on the Lake Hopatcong Commission Website at as the 2018 July and August Cyanotoxin Monitoring reports. (but results not available until September, long after people had NOT reported rashes from those levels). Obviously different people can always react differently to different bacteria, but certainly something to consider when you think the lake was essentially shut down for lower levels of cyanobacteria this year.

This data also flies in the face of the statements that the warmer water drives the growth, because almost every location around the lake (even Crescent Cove which was one of the BEST locations last year, B3/B4),got better in August than in July, similar to how this year also, numbers went DOWN during the summer. (confirming the 'first flush' of nutrients may be an issue, versus all rainfall being bad simply due to an 'extremely wet spring' which makes little sense, as additional rainfall dilutes the nutrients on the roads built up over the winter, etc, once the initial washing is done). This data also denies that the higher 2019 springtime rainfall caused a particular problem due to septics, since last year was no different or had higher cyanobacteria readings. And 2019 was even warmer water due to the drawdown which caused much less water near the shoreline, not climate change of course, yet Lake Hopatcong has been made into the nationwide poster child for climate change based on this year's DEP closure, while the lake actually did NOT have higher BGA levels than last year!

But what this data does show is a major increase in the cyanobacteria at station B8 between July and August, similar to the increase we see in nutrients each summer around that time. THAT is the deepest part of the lake, confirming that what we are really seeing is the material that is stuck at the bottom actually coming up as the thermocline and dissolved oxygen problems below happen. This effects nearby Mt. Arlington Beach (B5) nearby as well. The 2nd picture below are the locations for the 2018 cyanobacteria data.


This also shows that some of the best water in the whole lake is coming from Lake Shawnee and the canals, despite the shallowness and number of septics and lawns along a very narrow waterway. B9 had 113 (.1K) in July, while B10, the other water from Woodport (and quarry) mixing with it was 159K, 1400 times as much Blue Green Algae Bacteria! The highest in the lake coming from Woodport even last year, when we did have weeds, indicating that although my theory that lack of weeds provides more nutrients for algae may be true, we certainly have had loads of the cyanobacteria even when we have had loads of weeds too.

What this also shows me, in my opinion, is that this actually was a GOOD year compared to past years such as 2018, because in 2018, nobody complained about adverse effects from the cyanobacteria. Yet this year, the cyanobacteria provided light cover and prevented weed growth and made the lake very pleasant much of the time, having so few nuisance weeds in most of the lake, EXCEPT for the DEP reaction. Which we now see was more heavy handed this year on actually LESS of a problem than we had last year.

Of course much of this year's issues was caused by the DEP not following their own policy: Most other states as well as WHO and the EPA all indicate that decisions based on BACTERIA cell counts are to be done at the low levels only as low level warnings (certainly not 'do not touch the water') and usually only if you have seen that those bacteria have already caused your waterbody to exceed the toxin thresholds. We never even broke the NJ toxin threshold. Even New Jersey's own HAB procedure guide indicates that the bacteria is the signal to test for the toxins, but that the bacteria itself is a signal for advisory signs, but somehow that was not followed this year. And now we even know that last year was worse if one believes the DEP theory that cyanobacteria counts are how you should decide on the water quality, confirming that this year’s scare and shutdown was based on a situation that was even better than the year before!

The 3rd and 4th attachment are the 2019 data around the time the decision to kill the lake was being made, and locations. Bear in mind also though, that at that time, there were 'rumors' of rashes, and even a photo of someone who looked horrible in an article, but I personally investigated that and determined that same photo was used for years in Canada and upstate New York for other skin diseases, and NOT what happened at Lake Hopatcong. It’s unfortunate that instead of just having wisely erred on the side of caution initially, that the NJ procedure as published, which is to focus only on bacteria if toxins have failed could not have been followed subsequent to that though.


And on that note, I do also have to ask why the DEP is ONLY testing (or showing results) for microcystins in their toxin reports this year. As can be seen from the data from 2018, Anabaena Bacteria is also present in the lake, and its toxin, if created, based on CDC information, seems to be the toxin that produces the symptoms more similar to what the dogs in OTHER PARTS OF THE COUNTRY have reported, versus the microcystins that seems to be the only toxin the DEP is reporting for us. The NJ HAB Response document indicates that they also should test for Cylindrospermopsin and Anatoxin-a, not just Microscystins.   I just believe that we need confirmation that anabaena toxin and other BGA toxins are all being tested for, even if it means less planes instead. We should be made aware of the TOXINS present, as almost all studies and other states and authorities indicate that toxins are much more meaningful than bacteria cell counts.

Studies have also indicated that shutting down waterbodies based on cyanobacteria alone would cause huge impacts unnecessarily, and when you look at the 2018 vs 2019 exercise based on cyanobacteria, Lake Hopatcong seems to have clearly re-confirmed this.

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