Herbicide Treatment at Lake Zoar & A Few Smallies

Updated: Nov 30, 2020

To be upfront about it, this post will be less about the fishing Tom and I experienced that day, and more about the toxic, weed killing chemicals that were dumped into the lake while we were there.

Making the best of it before they poisoned the lake...

Upon arriving to the public launch around 6:30am, Tom and I were greeted by a couple of friendly bass fisherman, who were trailering a nice looking bass boat (I can't remember what kind, I'm a kayak guy). They asked us, "what made you decide to come HERE today?". We didn't know exactly how to respond other than telling them we wanted a challenge on an unfamiliar body of water. Tom had never visited the lake before, and I've been on Zoar only a couple of times with good friend Joe Jacobowitz on his boat.


Long story short, these guys informed us that the lake was being treated with weed killer that day. Great. The treatment was supposed to start around 7:30am. The bass boat guys were there to film the boat dumping the chemicals with a drone, and they planned to make a video to share on social media. The reason for this, to get horsepower behind a petition to stop using dangerous chemicals to "right" an ecological "problem". The chemical is known as Diquat Dibromide, and it is a toxic herbicide.


Tom and I reluctantly decided to fish anyway since we both drove an hour from our respective corners of the state, and I was sort of interested to see this chemical boat in action. For the record, I'm a fairly chemically sensitive person. I'm very effected by synthetic smells like harsh cleaners, soaps, perfume, air fresheners, etc. So I was a little nervous about this stuff they were about to dump into the water and into the air. I didn't know what to expect, or what potential level of danger was associated with being exposed to this stuff pretty directly. I've fished lakes that have been treated with this chemical or similar chemicals before, but I don't ever remember being there the day they did the treatment.

Tom with our new friends. Hopefully they are smart enough to move to a different body of water to eat vegetation that hasn't been laced with poison...

We left the boat launch and went up the lake. For those that have never been to Zoar, it is a large impound of the Housatonic River. It is long and riverine, with tributaries, deep water, and interesting structure with hard bottom. It's daunting, and has a reputation for being a bit stingy as far as the fishing goes. Tom and I started on the shady side of the lake, hopeful for some surface action and smallmouth chasing bait high in the water column. We were unsuccessful in our efforts, but we did see several smallies corralling bait. We kept our topwaters and unweighted Zoom Flukes nearby, but starting noticing bass and bait from 18-24' on our fishfinders. Tom has an insane setup on his Pro Angler 360, two 12" Garmin units, with one running Panoptix full screen. So yea, you could say he has a bit of an advantage over my Elite 7 Ti2. He was rewarded with the first fish of the day, a solid smallie that hit a Hula Grub.


Not much longer after that, while deadsticking a Fin-S fish on a 1/8oz jighead, I got smoked. Too bad I forgot to tighten the drag on my ultralight setup, and didn't get a good hookset. It felt like a good one too. We were getting bit here and there, but they were rather soft, non-agressive hits. I finally connected with a fish on a Ned Rig, just a little smallie of about 12".


We kept moving up, picking away at all the structure and marks we were seeing on the fishfinder, but weren't finding much in the way of cooperative bass. I decided to try a small Damiki Vault bladebait. Blades are more of a winter bait, and that was exactly why I tied it on. I thought to myself, "these fish haven't seen a bladebait in a minimum of 5 months, and maybe have seldom seen one during the summer, or at all". I took a long cast, parallel to the drop off, and let it hit bottom. It got hit immediately, but I missed the fish. The next couple casts were more of the same. I finally connected with a fish, but I could tell it was small. So small that I questioned during the "fight" if it was even a fish.

This may have been the smallest white perch I've ever caught.

Now we know what has been pecking at our offerings meant for smallmouth bass all morning... and they weren't all white perch. There seemed to be an eclectic mix of panfish all in this one area, including but not limited to yellow perch, rock bass, bluegill, pumpkinseeds, and redbreast sunfish. These fish were right on the bottom, and I can only assume they were feeding on zebra mussels or smaller fish that were eating the mussels, because if I wasn't bringing up a fish, I was bringing up shells off the bed.

Not much of a fight from these little redbreast sunfish, but they certainly are pretty.

At this point the wind started really picking up out of the northwest, and we decided to make a big move. There is no running and gunning in a kayak, so we moseyed further up the lake, stopping on various eye-catching spots for a cast or three. Tom restored my faith in this trip with a solid smallmouth, again on the Hula Grub, in only about 6' of water. The bass inhaled Tom's offering, and I rushed over with my trusty forecepts. It was deep, but not down the gullet. Skin hooked way back in the roof of the mouth. I was able to pop the hook gently, and the fish was released and swam off strong. That fish told us what to do for the rest of the trip.

Tom with his best smallie of the day.

We continued to pick away at the wood, weed and rock combination in about 6-10'. I stuck with the tried and true Ned Rig, and began picking away at the smallies. Most were on the less impressive side, but Tom and I both got a couple in the 2-2.5 lbs. range, which from what I am told by those who frequent the lake is a "good fish" for Zoar. As we fished through the spot and seemingly caught, missed, or lost every fish in the area, we decided it was time to head back down the lake. We were miles away from the launch and hours past when we thought we would be off the water.

My best fish of the day was caught on a Ned Rig.

On our trip back down the lake around 3:00pm, we heard this very loud motor around the corner inside one of the coves. It sounded almost like a cigarette boat, but I knew that couldn't be right. It was a shallow, weedy cove around this corner. We also noticed our bass boat friends sitting just outside the cove. As the noisy vessel came into view, we saw a fan boat spewing chemicals all over the weedy backwater slough. The company to blame and shame for distributing the chemical is Solitude Lake Management.

This was the evil boat that was basically poisoning the entire lake.

So, here is what I found while researching the KNOWN effects of Diquat on humans:


  • Diquat Dibromide can affect you when breathed in and by passing through your skin.

  • Exposure can irritate the eyes, nose, and throat and may cause nosebleeds.

  • Exposure to large amounts may cause severe poisoning with nausea, vomiting, diarrhea, tremors, convulsions, and even death.

  • Repeated exposure may cause clouding of the eye lenses (cataracts).

  • Repeated exposure may damage the fingernails, and cause cracked skin.

  • May damage the liver, kidneys and lungs.


The environmental effects seem to be far less documented, but MSDS (material safety data sheets) classify Diquat as a Category 1 Environmental Hazard. In case you don't already know, Category 1 is the greatest level of hazard. Fish, birds, invertebrates, any and all aquatic vegetation, reptiles, amphibians, and anything else that lives on the lake, drinks from it, or bathes in it, will be effected by these chemicals. Long term exposure also seems to be un-researched or undocumented, but there is no possible way that using this sort of chemical is good for the environment or humans. I'm certain the EPA is withholding data from the public on not only Diquat, but many other harmful "everyday" chemicals. Here is the link to the Diquat MSDS: https://alligare.com/wp-content/uploads/2018/08/alligare-diquat-herbicide-sds-v4.0-080618.pdf


It is appalling to know that the residents and lake associations of Lake Zoar would rather have a weedless area to swim (you're really gonna swim in there?) and dock their boats than to have a clean lake with healthy wildlife and fish to catch, and uncontaminated water to recreate in. To think this chemical is ONLY effecting the invasive vegetation is downright ignorance, complacence, and sheer stupidity. The scary part is that DEEP allows this to happen, not once, but several times a year, just to appease the residents who live on the lake. Aquatic vegetation is a valuable part of any body of water. It provides food for ducks and geese, a place for pike to lay their eggs, cover and shade for fish and aquatic bugs, and puts oxygen into the water. The other unsettling part of dumping large amounts of dangerous chemicals into Lake Zoar, is that it is part of the Housatonic River, which ultimately feeds into Long Island Sound. Zoar is an impound between two dams, and the dams are opened from time to time, meaning that poisoned water isn't contained within the lake, but will ultimately find it's way into Lake Housatonic, the tidal portion of the Housatonic, and out into the sound. I just can't imagine how anyone in their right mind would get behind using a chemical like this, and the fact that the DEEP permits it's use is mind-blowing.


As Tom and I were getting off the water, we did notice our eyes to be burning a bit and our throats were sore after having to pedal through the area of the lake that had already been treated, and that was from maybe an hour of being in indirect contact with the chemical. It was disheartening to know this sort of thing has become "the norm" in American society. There has to be a better solution than "Just dump some chemicals on it". Look at Round-Up for example (I will spare you the rant). Weed harvesting boats, though not cheap, would be a much safer long term solution for places like Zoar. Also grass carp...


Here is a link to the Facebook Page made by the friendly guys in the bass boat, who will be petitioning for a cease and desist on future Diquat treatments on public bodies of water: https://www.facebook.com/Citizens-against-Diquat-Debromide-225863272199936



-JR