Explain this one please

Iv been watching our lakes rise online, mostly the ones in central Texas and on the Brazos river basin. Almost all of them, with the exception of Belton and Stillhouse are above conservation pool. Both of these 2 lakes will soon be above conservation pool at the rates they are currently rising. Last week Whitney, Aquilla, Waco, and Proctor were all above conservation pool and releasing water. Now with the recent rains and flooding downstream they have had to pretty much close the gates on all of them. I understand that part.

What I dont understand is the site I am watching now is showing Granbury to be .39 below conservation pool and they are releasing 6800cfs. This lake hasnt even filled up yet but they are already releasing a good amount of water. Im not familiar with the area around Granbury so can someone please fill me in on the reasoning behind this?

I use this site, but not too sure about where Granbury should be as far as level..http://nwis.waterdata.usgs.gov/tx/nwis/uv/?cb_00062=on&format=gif_default&site_no=08090885&period=300&begin_date=2015-05-19&end_date=2015-05-26

From TPW
Water murky; 67–71 degrees; 0.10' low. But, they could be letting water out to get ready for something... Houston just got Flooded...

http://www.empowertexans.com/economy/the-plot-to-drain-possum-kingdom-and-lake-granbury/

Still a huge influx of runoff being caught upstream in the Brazos.

I understand that may be the case upstream but in the middle and lower Brazos basins we are also receiving a large ammount of runoff as well as water being released from lakes upstream. All this with more predicted rain in the near future.

Seems to me the best idea would be to start lowering the lakes that are suffering the most downstream and work you way upstream as conditions allow. One thing is certain, once that water makes its way downriver, there's no way to move it back up.

Granbury is not a flood control lake. It doesn't have the ability to hold back much extra water. It they hold back water it will flood all of the houses built around the lake.

Jerry, lake Granbury was built and designed to be what is called a constant level lake, and is extremely residential. The dam is very efficient and can let water out as fast as it comes in except in extremely serious flood conditions. With that being said a lot of the residences are very near the water level and single digit numbers high could cause severe residential flooding. The BRA will do its best to manage Granbury at near or just under full pool when it does not cause major residential flooding at lakes up or down stream. Not saying high water conditions do not effect residents at PK or Whitney just the majority of those residences are not as close to conservation pool by design. Just my thoughts from observing this section of river for quite a while.

Or more simply what Brian said.LOL

Thanks guys. I didn't know it was a constant level lake. I understand now because I am familiar with LBJ.

It's not a constant level lake, the BRA just tries to manage it that way when possible. I suspect they are anticipating more flow upstream.

I just saw a post on facebook via DFW Scanner where they are about to open 3 of the 4 flood gates at PK. Expecting this would certainly account for the release of water out of Granbury. Post also advises of a neighborhood evacuation out south of Weatherford.

Here's part of the reason I am asking this. Look at the rivers in the brazos river basin. Looks to me like most of the lakes farther downstream are higher above conservation pool than the ones upstream. Releasing water upstream and holding water downstream will only make downstream lakes suffer more. Keep in mind ALL lakes are still reciving run off from recent rains and we have more rain predicted in the near future.



Just trying to think ahead a little bit. I think all we need is 1 more line of storms and a number of lakes, rivers, and communities could see some serious high water for a prolonged period of time.

A lot of the lakes down stream may be holding water back for rice farmers.
My Dad was a rice farmer 50 something years ago and they must have water.May be wrong by that is my 2 cents worth.

I know belton always has to release water to rice farmers. That's why it gets drawn down so much in the summer. Do you know how late through the year they need water? I don't see a shortage of water for them this year but I may be wrong.

All I can say life can be tuff at times . Chicken one day and feathers the next.
We all will have to play the hand the good Lord has laid out for us.

Well said freeman!

Think of it this way... COE lakes...such as Whitney...are flood control lakes. That is their primary purpose. The COE will release back to conservation pool as soon as downstream conditions allow.

In the case of Grandbury, the Brazos River Authority Authority's released below pool because of the situation that was likely, and subsequently has developed. The much larger PK needs to release.

I know there main purpose is to prevent flooding. That's pretty much the sole reason I started this thread. To discuss preventing potential flooding.

I guess my next question is why is it so crucial to keep pk below conservation pool?

Uped it to 35000

And the plot is still in effect looks like.

It's called "controlled release". Neither lake is coming down very much with all the water they are releasing.
In fact PK is still rising........ COE says Whitney is going to hold the water until they can release in a safe manner.
There are people that live on the Brazos below Whitney. (WACO) You can't just turn all the water loose at once ....
No-one is releasing water to drain anything..... I don't think anyone downstream needs any more water.