I have a 6 acre pond in south central Kansas. We have recieved very little rain since Sept. of 2005, we didn't get any of the heavy spring rains we normally get last year. The pond is about 7 feet low. My question is, would a solar powered pump be powerful enough to maintain a reasonable water level once the pond fills back up this spring?

Welcome, badg53.

You would need to create a water budget that would involve the following unreported factors.

1. Amount of water volume lost during drought.

2. Amount of time it took to lose the water.

3. Divide the two to come up with a water volume lost per day during your recent drought.

4. Amount of water that entered the pond during that time from rainfall and runoff.

5. Add "4" and "3". This will give you a seepage and evaporation total per day.

6. Amount of expected rainfall and runoff during a normal year.

7. Divide "6" by 365. This will give you a natural inflow expected per day.

8. Subtract "7" from "5". This will yield a figure that would be termed "expected net daily loss".

9. Now ask the manufacturer of your solar pump how much water should be pulled up given the amount of depth to your water table. If figure "9" exceeds figure "8" your pond will stay full. If not your will need to figure out if a larger pump or an electric pump will give you enough water to maintain your level.

Just so you know...I'm guessing the answer to your question will be "no".

More simply put Rainfall + runoff + water pumped in - evaporation - seepage needs to be a positive number.

Again, welcome.

Bruce, If I did the math right it looks like .34 inches expected net daily loss. That translates into about 1/3 inch per day. If an acre foot of water is 425,000 gallons an inch would be 35,416 x 6 acres is 212,496 gallons per inch x .34 is 72,249 gallons per day that I need to put back. That's going to be one heck of a pump. Thanks for the information.
badg53

Now I'm assuming that you've historically had the rainfall necessary to fill each spring. Is there a cheaper way to capture more summer and fall rains, such as creating a terrace?

.34 inches per day sounds a little high. Often people will underestimate how much water comes in during a runoff event. Especially if this runoff event occurs on saturated soils.

I'm in a fairly arid area and I have an expected loss of about .19 inches per day from June 15 through November 15.

badge53 welcome to PB.

awesome post bruce.

i am just beginning to look into a solar powered pump set up for a well that i havent drilled yet......you can see this is gonna be a lot of help to you

anyway, i am waiting to hear back from a guy (an electrical contractor i met) who told me of a system that runs about $3,500. its a solar cell and battery system that can reportedly do 25,000 gallons a day, which translates to roughly 17 gpm. thats probably on the low side of what you need, but would suit me just fine. Some of my questions on this system? I dont know the max HP pump it can run, nor from how deep it can pull. I'll try and remember to report back here with more detailed info if interested.

I just edited my first post. I think I made an error. It should be corrected now.

Lots of useful solar power and pump info on the "backwoodssolar.com" site.

Badg, An acre ft would equate to 325900 gallons per ft (vs 425000)or 27158 gallons per inch, This does not change your results much but may bring your calculations a bit more in line. I have a calculated loss of 3/10th - 4/10th per day from June -Sept, some seepage most evaporation.

I'm interested in hearing more about this Dave. I'm thinking of adding a solar well and holding tank for drinking water. Let me know what the contractor says.

no prob jeff, i'll send you a pm when i have something to report.

that is actually a little less than I thought I would have to spend. Out here the drillers have a 100' minimum, we'll hit water at about 30' in my area but I can't afford to put down 2 wells because we're not sure of the volume we have.