Evaporation Rate

[buckry]

I filled my pond up to the brim last night as it was a couple inches low and it's already back down to where it was. I don't believe I have a leak, but in the middle of the hot summer how much can I expect to lose? Does the waterfall flowing over my rock cause a lot of water to evaporate? The pond liner itself definitely doesn't have a leak, and the water fall seems to be water tight, there is no evidence of moisture anywhere around it.

Is an inch lost in about 24 hours reasonable in 90 degree heat?

 

[taherrmann4]

Lot of variables play into this. Do you get a lot of wind? Does your pond sit in hot sun all day? The amount of surface water/creeks/falls.

I lose about 1" every 3 or 4 days in the hot summer months, but I am in a very windy location have a lot of surface area,
pond is 12x15,
12' waterfall/creek,
20' creek,
10' creek,
8x6 bog
So I have a lot of surface that the wind/sun can just suck the moisture out, but I don't lose it that fast.

 

[don't ask]

Buck, i'm with you as there are times i see my water level is fine each day and then all of a sudden it seems to drop like an inch..tmann i think hit it on the head as far as how long pond is in full sun, wind, water splashing from water fall or other features and i would guess also the number of plants in pond that are taking up water so they wont dry out.. I was just thinking maybe marking the liner and then measure how much it drops each day..would also keep note on temp, full sun or clouds, etc as that might help trying to figure if evaporation or some other reason

 

[buckry]

Well, I have 1 X factor I found, and pretty much every item on your list describes my pond. It's in full sun from noon until 7pm, my plants are not established yet so I'm sitting at 10% coverage, maybe 15% with my bridge. I have a 20" waterfall, then a 12" waterfall and a 4' stream. The pond is also next to my air conditioner condenser unit, so when it kicks on it's sucking air over the top of the water.

The X factor I found is I tucked spanish moss all around the liner and it was sitting down in the liner at 3 places where water was collecting. The moss was whicking up the moisture where it then evaporated right off. I doubt this is my major problem, but every drop counts. I removed all of the moss, we'll see if it impacts anything.

 

[taherrmann4]

If you want to find out what your evaporation rate is, take a 5 gallon bucket fill it with water and mark a line where the water level is, then 24 hours later go out and see how much it has dropped. You will need to put the bucket next to your pond so it is in the same elements as your pond.

 

[taherrmann4]

Keep in mind also the amount of water that goes over your rocks on your waterfall and if you have any constant splashing this is going to accelerate it as well.

 

[buckry]

Yeah, I might as well do that, would be good to know.

 

[fishin4cars]

That's a really good idea to try and find out how much is a average of loss. It won't be exact but close. I would think a 1" in 24 hours is a bit much. Even in south La. with Temps well in the 90's and full sun all day I'm losing about 1/4"-1/2" a day tops.

 

[buckry]

I think I might have mis-measured, My overflow area isn't able to release water as fast as my hose so when I get done filling it to the brim, it's actually over filled, so then I looked at the liner and where it was compared to the water, and went to bed. Today the water level was an inch lower, but this is evaporation AND who knows how much water that drained out over the top of my liner. I shored up that edge so it should be a lot less missing tomorrow.

 

[addy1]

I have tweaked my overflow a few times, think it is finally where I want it, maybe lol

Hope that was your problem.

 

[buckry]

Yeah, woke up this morning and the water is still lapping at the rocks, so I think I just pumped in an extra inch over where I should have been, then that drained slowly out overnight, then lost another 1/4" in evaporation. Those two things looked like a ton of water loss, but it really is only a little bit.

 

[JenH]

I get a ton of evaporation with my set up. I was worried it was a leak but if I refill after the sun goes down on a calm night I don't lose any water, so I know it's not a leak. But I have my waterfall, and my bog with very shallow water at the surface, lots of plants, full sun from the time the sun comes up until it sets, and it's usually windy in my backyard. For me with our Indiana weather right now I am losing about 1/2 - 3/4" a day. I also have a couple plants that I suspect probably drink a lot of water. The roots for my water forget-me-nots just float, not planted, and there are 2 fairly large blankets of it in my pond. I'm sure that drinks a lot, bt the flowers are so pretty it's worth it to top off everyday.

Where are you located in IN?

 

[pugle1]

I also lose about a 1/4 to 1/2 inch of water per day. We've been in the low 90's here for a week or so. I top-up to my over-flow, then just let the water level out where it wants to. My mini cattails are still in a pot, and that's what I use to gauge my water loss. The brim of the pot is right at the water line when the pond is filled to capacity. I know to add a little water when the level drops to the bottom edge of that brim. That's about every two days. I was also scared that it may have been a leak causing this water loss, but it's just so warm here (and windy) that I figure it has to be evaporation. During cooler, cloudy spells, the water doesn't disappear nearly as fast.

 

[buckry]

Yeah, the bucket has lost nearly 1/4" so far, and it looks like the pond is down a bit more than that. I think I can safely say it's not a leak and that's all I care about.

Where at in Indiana are you Jen? Logansport here.

 

[addy1]

bucky, 96 here, no real wind, but full sun.

A lot of surface area and I ran the stream most of the day to keep the deck pond cooler. My pond dropped about 2 inches. I know there is no leak, even without the stream running it will drop level on hot days. I have a garden hose attached to our garden irrigation system, gives it 1/2 hour of water every other day to keep it filled. sometimes I need to add more, if it stays hot like this I will need to add water to it every day.

Long story short you have evaporation..........I used to think leak, but over time you learn the rhythm of your pond.