Pond Boss Forums POND CONSTRUCTION Selecting a site Diggin' in the Lowcountry -- Advice needed

Well, the old timer was correct on the slope. no way to keep sand in place at a 2:1 slope. 3:1 is marginal, 4:1 better.

Here the soil was pure sand to 10', then hit a 12" layer of gravel, then a 12" layer of clay, then another 8' of pure sand, then 12" gravel then blue clay. We dug to 22' depth, and had to pump every day so we weren't digging in water. We had to move the pump down as we dug down, the pump wouldn't suck water up very efficiently. We made a shelf with the excavator, put a sheet of plywood on it and angled it slightly back towards the bank - if we didn't do this the pump would vibrate and walk towards the water.

We also had to put the pump intake thru an inner tube and float in in the pond, keeping the intake about a foot to two feet below the surface and tied with a rope from the other side of the pond to keep it from floating to shore. First time we left it on the bottom the intake hose filled with sand and we ripped it picking it up with the excavator to empty it out.....

You can use a 3" semi trash pump to pump out the water, to get the water moving faster adapt the outflow to 4" pipe as fast as possible, the roll flat hose always kinked on me, I ended up using a very short section of it then transitioned to 4" belled end drainage PVC, thinwall stuff. Drained a 1 ac, 8' max depth pond in 4-5 days with a 3" semi-trash pump. I disconnected the fuel tank on the pump, plumbed it into a gravity fed 6 gallon old metal outboard motor gas tank, sitting higher elevation wise than the pump. I drilled/soldered a fitting to the low point on the side of the tank, I found out that the pump sucks gas so slowly that running it like an outboard motor (out the top of the tank) always developed a slight air leak and lost "prime". The pump would run about 18-20 hours on that 6 gal tank.

As to what is possible with the excavator, that all depends on the operator and the time he has to do the job. We used a Komatsu PC200LC-8 Excavator and had to dig in 2 stages, handling the dirt twice. IIRC it had a 1.5 or 2 yd bucket. This pond is 1.1 or so acres when full, max depth was 22'...... We used a pan scraper in the beginning pulled by a tractor, then the excavator, loading a dump truck to move the dirt away from the pond. An ASV skid steer and a dozer was used to distribute the dirt evenly on site, but we did truck 2,700 cu. yd. to my parents place 7 miles away to build a pad for a pole barn and to level out the ground between the house and the pole barn. We used a backhoe on site to load 2 dump trucks and the ASV at their place to distribute the dirt. We moved that 2,700 yds in a weekend..... (2 LONG days)