Texas drought. Well issues

[Kenster]

We are well into a several year's long draught here in Texas. (Extreme draught in this area) but this is the worst year in decades. Our well is 125 feet deep. The pump was replaced about five years ago. We have plenty of water for household use and great shower pressure at night, but, if we attempt to water the grass around the house with even one little circle style sprinkler, the pressure drops off to almost nil within 20 minutes or so. When I first turn the sprinkler on it will water a circle of about 15 feet, then will drop off to barely three feet. If I turn off the sprinkler, pressure will slowly rebuild and be back to normal after several minutes.

I talked to our local well guy two years ago when we were going through the same thing. He said most likely it is simply a slow recharge at our pump due to the lower water table. To my understanding, when they sink a well, they blow out a pool way down there and that pool is the source of the water that the pump picks up. He said that they could try blowing that pool out again because it might have filled up with sediment, OR he said they could go down another 100 feet or so, which would run about $10 thousand dollars.

Now my neighbor, whose house is about 75 yards away, waters with at least two sprinklers nearly every day. He has great pressure all the time. He said his well is also at 125 feet. (Same company put in all the wells around here. Probably most of the wells in the county.) The well guy explains this disparity as being an issue with the rock down there and how the underground water table flows. Pockets of water. That sort of thing. He either has a naturally better recharge rate, or a larger 'pool' down there, or both. The neighbor waters, probably an acre and a half around his house. We just want to keep a wee bit green grass immediately next to the house, if for nothing else than due to the fire dangers we are having.

In a worst case scenario we could always hook back up to the community water system but I hate to do that.

Any suggestions, thoughts, guidance, or education in how wells work is appreciated.

 

[semipro]

I think you have four choices: 1) increase your above ground water storage capacity; 2) modify the existing well; 3) drill a new well; 4) some combination of two of the other three.

The first involves adding storage tanks whether pressurized or unpressurized. You can fill the tanks at whatever recharge rate your well will handle and then discharge them at a higher rate when needed for tasks like watering.

Modifying the well may involved drilling it deeper, blowing it out to remove accumulated sediment or something else I don't know about.

You already know about the 3rd option.

For the 4th option, maybe you could clean the existing well and then add some additional storage.


$10k for 100 ft. more depth on your existing well seems really steep to me though. It might be worth doing a little shopping around. Driillers are used to traveling pretty far to do a job. Don't just use the local guy because he's local.

 

[jimbom]

Should be a wealth of well information about your area available. In Missouri, I can go online and get well records for most wells. From the well records, you can tell if you and your neighbor share the same aquifer and have the same soil layers. If the wells are close, they should. If both wells are in the same soil, then the recharge rates will be the same. That will tell you if something is wrong with your well/equipment or you really do have a different water source. If you have other neighbors, do they have any problem?

I don't know about your pump, but you may have a plugged screen or something wrong with your pump. Do you have a kink in a line or some place where the line has been squeezed underground. Is any of this still under warranty?

Generally in wells and soils, local knowledge trumps. If this well driller is on the up and up, he will know more about your neighborhood than most.

 

[Kenster]

This guy and his dad have been doing wells in this county for probably 50 years. The dad passed away a few years ago. The son has always been in the business. Good, reputable family and the 'go to' guy for pretty much everyone around here.
My neighbors well is maybe 150 yards from mine. Same elevation but we are both on the high spot of a big sand hill. Everything slopes down from our properties. I don't know if that affects the hydrology (is that the right word) of our two water supplies. The fact that we have very deep, fine sandy soil is why the well guy thought maybe the "pool" could use a little blowing out. My understanding is that they force high pressure back down the pipe into an elbow fitting and the water pressure blows out a big pool down there and that is where the pump sits. I guess they have to suction out all that dislodged sand and sediment before it settles down again.

Haven't heard of any problems from other neighbors. We are in a mildly rolling topography so the dynamics could be different on every property. As for a kink in the line.... I would think a kink would effect us at all times, whereas we only have this problem during lengthy dry spells. And it only effects us when we run a lot of water, as in watering the lawn but the pressure always starts off very good and maintains that pressure for up to half an hour. I think a kink would cause low pressure from the beginning. Fortunately, we never have a problem in the house. We have new, high efficiency dish washer and washing machine. Usually only run them once or twice a week. Very powerful showers in the evening. Only two of us so we don't use much water.

I'll give the well guy a call and refresh the conversation I had a couple of years ago.

What do you think I should look under for well records?

 

[mecreature]

the depth of the pump in the well plays a big roll in what your reserve/head is.
Ideally you would want the pump shallow enough to have room below for sediment and deep enough to have good head. and adjust from there for recharge.
I had a well drilled last year.. that is what I got from the guys.

check out some of your local college web sites.

 

[jimbom]

This is the location I found for well logs in Texas:
https://texaswellreports.twdb.state.tx.us/drillers-new/index.asp

From your description of sand aquifer, my thought would be with Mecreature. The depth of the pump installed five years ago could be an issue. Between the well log which should tell you the depth the driller hit water and the depth of the hole you would have how much water table you have to work with. If your work documents five years ago gives the down hole distance of the pump, you could tell the vertical location of the pump in the water.

You might explore with the driller if the controls could be adjusted to run the water level down closer to the pump. When they install a pump, they adjust the controls to insure water remains over the pump at all times. This keeps the pump safe and keeps any contaminants floating on the surface of the aquifer from fouling your well. It may be you could have a little less factor of safety.

In the final analysis, more wells and less recharge in an aquifer result in a lowering of the water table. Then everyone has to drill deeper wells. Might be the case here. By going down another 100 feet, the driller is trying to keep you in water for the longest time. That is a good thing. However, if you are not going to live there for the next 30 years, you may not want to pay for such a deep well. Also, the rainfall may return and recharge the aquifer, solving the problem in the long term for free.

If this driller has a good reputation and strikes you as honest, you may want to listen to his advice. The guys that work with this everyday have excellent grasp of what works and what causes call backs.

 

[drozenski]

Why are you wasting water on watering your lawn?

If you want a green lawn but are in a drought area then look into getting a fake lawn.

 

[Sisu]

Other things to consider is that your well pump could be having problems or undersized, well screening could be plugging up, or you could be having issues with your pressure tank. But if you are in a drought area, I wouldn't waste the precious resource to keep the grass green. Look into other lawn coverings/options that don't require help with hydration.

 

[gpcollen1]

Why are you wasting water on watering your lawn?

If you want a green lawn but are in a drought area then look into getting a fake lawn.

I would look to fix the well situation even if the lawn does not get watered. Though I agree, watering the lawn is the last thing anyone should be doing in a drought - or even regularly anywhere, IMO.

 

[Kenster]

Why are you wasting water on watering your lawn?

If you want a green lawn but are in a drought area then look into getting a fake lawn.

We just want a little bit of green about 10 -12 feet around the house. If for nothing else than to help keep potential grass fires away.

 

[HeatsTwice]

"What do you think I should look under for well records? "

Out here in California, drillers are not required to publisize their drilling reports (how deep the water is, what the strata is).

But publicly held properties (municipal golf sources - which usually have more than one well, and other city/county owned properties which have wells) are required to publish them. If you have any such property near your house, getting this info is just a matter of approaching the city permit department.

Also, money well spent is to hire a consultant. Eugene Boudreau is the best I have ever run across. He has 50 years of experiene as a hydrologist (University of Cal Berkley) and if you call him to describe your problem, he will probably advise you free of charge. Even though he is not in your area, over the phone, he can get a clear description from you by asking the right questions, and then advise. He may even do it for free as he is retired but still loves his job. For contact information, just search the web for "Eugene Boudreau well water". He is famose in these circles but a very humble man. The ony advice I stress is this: DO NOT BRING UP WATER WICHES in your conversation if you call. He considers them con artists and will site USGS proof and then for the next hour you will hear about it.

Having drilled a well of my own, my solution to your problem was to install a 500 gallon holding tank and a booster pump. Althought the well only puts out 5 gallons per minute, with the tank and booster pump, I get 17 gallons per minute at 65 psi for 1 hour and 10 minutes. Far more than what I actually need. The whole setup fits on a 6' x 8' cement pad in the back of my property. In hind site, since I have so much room, I should have put in a 2000 gallon tank since the price for one is not that much more than what I spent on the 500 gallon tank.

The booster pump, bladder tank, and holding tank cost me about $5K. But I easily recoup'd that cost over the 5 years I had it since my water bill went from $350 per month down to $30 for electricity using even more water than before. Also, the well and boster setup was factored into the over all market value of my house durring a recent refinance. The well brought its value up by that dollar amount.

 

[homebrewz]

Its been a long time since I took hydrology, but here goes.

Is your well completed/finished in sand (and/or gravel) or bedrock? From what I've read.. 125' deep well on a sand hill, I'm going to assume its completed in sand or otherwise unconsolidated material. When they drill a well they're tapping into the water table, or the saturated zone of water below the ground surface. When they are done drilling, they typically "surge" the well. Surging is the process of blowing compressed air back into the aquifer. This helps loosen up "fines" or small particles of sand/silt/clay which can impede the flow of water through the aquifer and into the well.

If you'd like to picture what your well looks like in cross section, take an aquarium and fill it halfway with sand. Then take some water and sprinkle it over the sand. Eventually the water will percolate through the permeable sand and fill up the lower zone of the aquarium. The water now exists in the tiny spaces between the sand particles. Drilling a well is like sticking a straw into the sand to get at the water below the surface.

You can think of the surface of the water table as fairly flat, probably with a slope towards the downhill direction. The top of the water table can be mapped in contours, like a topographic map and it often mimics the surface topography. When you draw water out of a well you are temporarily lowering the elevation of the water table around the well. This is called "drawdown" and in 3-D it kind of looks like a cone or a funnel (called the "cone of depression"). For wells completed in unconsolidated materials, sand, gravel, and up here in the north.. glacial till, when they set the pump, its important not to set it too far down the well. If the water table is drawn down very far its possible that some compaction of the spaces between the sand particles will occur.. this will eventually effect the rate at which the well recharges, or refills with water. Re-surging the well can sometimes help this.

In your case, there are probably several things happening: Your area has been experiencing an extended drought, so the water table is lower anyway. There may have been some new home construction in the area in recent years increasing demand on the aquifer and thereby lowering the water table. Your well screen and the surrounding area of the aquifer may be partially plugged up with fines. Re-surging the well ("blowing out the pool" as you said) may help this.

I'm not sure if I would drill deeper without finding out a few things. I would certainly ask neighbors within a 1/2 mile radius how deep their wells are and how the flow is (the problem with this is that most people don't know or may be off by several 10's of feet). This will give you an idea if going deeper is even an option. If the problem persists, but only occurs with the extra demand, its possible that the problem is with the lowering of the water table due to the circumstances above. In that case, the storage tank option would be a good idea. You could also consider rerouting your gray water to be re-used in watering the lawn. This is a design that is being incorporated into "green" building design. Though, you may have to change what type of detergents you use and run it through some type of filter.

If you want to know more you could try contacting whoever teaches hydrology/hydrogeology at the local university and asking some informed questions.
I hope this helps!

homebrewz

 

[begreen]

Why are folks watering lawns in a bad drought? That seems nuts, especially when the aquifer is getting low. Out here we just let it go brown. It greens up again when the rains return. If you want green lawns in a drought, paint the grass or install astroturf. But don't waste water. No one knows how long the drought will last.

http://www.grassbgreen.com/