Thanks for the update! On the crappie forum someone posted seeing HUNDREDS of dead fish of all species just yesterday afternoon. That's over a week and one good gully washer after the first report here.

I finally wrapped up work with some sunlight to spare so I went down to the creek with my wife and daughter to scope things out.

There is an obvious algae bloom with some sort of bubbly clumpy algae (the clumpy algae is harmless I assume). The water itself was abnormally clear for just a few days after 1" of rain. Water was trickling in at the inlet in the earlier video.



Most of the sandbass seem to have been dead for a few days but here is one that must have died recently as it's eyes were still clear.


The oily sheen shows up here and there. A lot of spots have orange / reddish stains on the water's edge.


There were dead fish as far as I had time to walk. 1 mile downstream and 1/2 mile upstream from the bridge. When the water rose it dropped a lot of fish a few feet off of the bank. It's clear the fish kill has come in waves and had reached far upstream from the bridge since with the recent rain there would not be much of a backflow. Here is a pod of dead carp.


Golden algae shouldn't kill turtles?




It seems like entire schools of sandbass were wiped out at the same time a few days ago.


The most dead fish were around the bridge but I think this is simply because the commotion of the cars scares away the predators. There must be a lot of fat skunks, possums, racoons, coyotes, etc. There were some beavers in the creek that seemed rather active I guess. Here is a mix of sandbass, rough fish, crappie, LMB, etc.



Overall I just have a sick feeling now. We need a lot of rain!

this terrible. I can only hope it was reaction to a natural occurence,
& not caused by somebody poisoning the water.
that's just inexcusable to me, 'specially if it's a rancher or ag-farmer.
I guess we wait for the water report.......

Sad Sad sight!

I was so excited for that spot this Spring...

I live over in Paloma and This is terrible.

Man, that looks bad. Almost looks like fertilizer or something with all the algae growth. Did anyone see if it extends over to the elm fork just west of there?

Hell yea it's fertilizer!!!! I live right here too and every lawn within 50 miles has put it on this year and the excess runs right to the lake. The street drain on front of my house has a cover on it that says "no dumping empties into lake lewisville" I think the problem will be compounded with the stage. 3 water restrictions.... It will cause more fertilizer and higher consentrations of chemicals on the lake.

+1 regarding fertilizer.

Thinking about it more, the start of the fish kill was when we got a little rain and it's focal point was the little stream at the beginning of the video (run off from 100's of houses) where the outflow is now choked with a "healthy" algae.

Looking at the USGS charts for this creek, in 2014 the PH pushed up to 9.2 a few times this year which is as high as it's reached since the PH meter was installed in 2008. Although it's probably natural due to the limey soil, I think that's right at the limit of what most game fish can survive. That high of PH is going to effect the sort of algae that will grow from what I've read, causing the nitrogen levels to spike.

Another factor is that they stopped pumping water into Lew from Cooper for a few weeks earlier this year. Usually there is a backflow of "cleaner" water into the creek but it wasn't there for the last few weeks. The only "current" for a few weeks was when the wind picked up or the periodic "soapy" release from the water treatment plant.

That was my concern as well Tony...that water treatment plant is awfully close.

Here is a segment from the biologists report for the Little Elm creek fish kill.



"Last Friday I investigated a fish kill on the Little Elm Creek arm of Lake Lewisville at Hwy 380. The majority of fish were immediately upstream and downstream of the bridge. However, I did observed dead fish approximately 1000 m upstream and downstream of the bridge. Fish kill counts (11 species; n = 509) included 433 white bass, 22 common carp, 1 largemouth bass, 9 white crappie, 11 smallmouth buffalo, 3 channel catfish, 10 spotted gar, 2 bluegill, 5 flathead catfish, 1 freshwater drum, 12 gizzard shad.



The fish kill appeared to be several days old, with the freshest fish looking approximately 24 hours dead. I did not see any signs of pollution, pH (6.4) was slightly lower than what I would expect for this water body, and the UTRWD sewage plant upstream of the fish kill reported that their plant has been running with no issues for the last several days. There is also a UTRWD drinking water plant just upstream of the fish kill. It does not have an outfall to Lake Lewisville and operators there reported that the plant has had no issues in the last several days.



At this time this fish kill has no suspected cause. I collected a water sample that a plan to send to our lab in San Marcos to rule out the slim to none chance the kill was due to toxicity from a golden algal bloom. With several of the fish observed with hemorrhaging around fins and under scales, and the presence of spotted gar, I do suspect there could have been some type of toxicity involved to cause this fish kill. It is very unlikely this was a low dissolved oxygen fish kill."

Thanks, Carey.
curious if they are only testing for GA, or for other
toxins or petrochemicals

That's good info, thanks Carey!

The dead turtles are another oddity. They would be more hardy than even gar I suspect. I wonder how the water is PH 6.4? Perhaps that's due to the rotting fish, but it seems unlikely that they would change the water chemistry that much. Out of curiosity I checked the USGS site and the most acidic reading in TX was currently PH 6.9. I suspect that you could measure the PH all around Lew or any of the DFW lakes for that matter and you'd not find an acidic PH reading anywhere.

Thanks for the report and notifying the Game Warden. Not sure why anyone would fertilize their lawn in March, you're just fertilizing the weeds and encouraging weed growth.

A bit off-topic but late Mar/early Apr is the recommended time to fertilize in NT. Likewise, many people have a weed killer in their fertilizer. No doubt all of the recent building around this creek could be a culprit but unproven at this time. Hopefully, the additional tests and reports will help us understand this situation.

Thanks CareY!