Help designing pond

Hello

I have runoff from a river which runs once or twice a year and brings about 16000 m3 of water a year. I want to build a pond of about 4000m3 to collect the water. Can you please help me design it.

I have attached a topographical map of the land. The water enters from the North at 266.62.

Thank you

There are many variables to design of ponds.  Essentially the only thing in common between ponds is that they are holes in the ground.
Things you need to know would include:

Type of soil where you intend to dig.
Are there rocks in the soil?
How far down is bedrock.
The shape of the desired pond, how deep/shallow
The uses for the pond. (Fish? Irrigation? swimming? )

Hi

The soil is a clay soil

Not sure where the bedrock is but I've seen them dig a well nearby and all they were getting was this grey hard clay after about 2 meters of digging. Looks like the stuff in the picture.

I want to make a 5 meter deep pond with about 2 meter high walls around. So total of 7 meters depth. The shape will be rectangular. About 30 metres x 50 metres

The pond will be used for irrigation, fish and swimming.

Regards

That looks like perfect soil for building a pond.
Sounds like you have the plans already decided for what you want to do.

Here is something that might interest you to handle overflow of water:

https://permies.com/t/1360/Sepp-Holzer-ponds-monk

Yen Yus wrote:Hi

The soil is a clay soil

Not sure where the bedrock is but I've seen them dig a well nearby and all they were getting was this grey hard clay after about 2 meters of digging. Looks like the stuff in the picture.

I want to make a 5 meter deep pond with about 2 meter high walls around. So total of 7 meters depth. The shape will be rectangular. About 30 metres x 50 metres

The pond will be used for irrigation, fish and swimming.

Regards

Holy cow, I thought I had clay!

Here are my measurements.

Yen,

I noticed from your initial post that the rains only occur a few times a year and they bring ~ 16,000 cm3 (4,226,752 gallons).  You want to capture ~ 4,000 cm3 (1,056,688 gallons).  Chris posted a link regarding Sepp Holzers "monks", but I think you will have to deal with a lot more water flow than a typical "monk" can handle.  Basically your pond will have to handle very high flow rates at very sporadic intervals.  You need a design that can send ~ 25% of the flow to the pond and the remaining 75% is diverted safely around the pond so that the ponds "spillway" is probably never utilized.

With clay like you showed in the photo, I doubt that infiltration losses will amount to much.  What about evaporation?  Where (generically) will this project be located?

Have you contemplated the equipment needed to perform this project?  This is a fairly large earth moving project at 4,000 cm3 (5,231 yd3)?

I have more questions, but answers to these will help direct future responses.

Thanks,

Kevin

Kevin Elmore wrote:4,000 cm3 (5,231 yd3)

"cm3" is an abbreviation for 'centimetres cubed'.  You probably mean cu.m or m3 or m³ since you're talking about cubic metres.

PS:  Just in case you weren't aware already, you can uncheck 'Disable HTML in this message' below the editing box and type in &‌sup2; to generate a ² or &‌sup3; to generate a ³ (e.g. 4000m&‌sup3; displays as 4000m³) — useful superscripts for areas and volumes.

PPS:  If you end up with unwanted smilies in your post, just check 'Disable smilies in this message' below the editing box.  This will happen if you have an area or volume within brackets because the last two characters — ;)  — are otherwise converted to a winking smilie.

Hi guys

The pond will be in Cyprus. I calculated a loss of 2 m3 per week per 50 m2 during the hot season which is around 6 months.

Im thinking of using diversion swales on each side of the pond to take excess water off my land and also further infiltrate the water into the land.

Earthworks is going to be a big job. We will basically use the biggest excavator we can find. Im just trying to figure out what to do with all the extra soil and clay that comes out.