Putting gravity to work

 We all know that gravity can be a drag (pun intended) when you're running uphill, trying to lift a heavy box, or trip and hit the ground with a thud.  So when we can actually put this force to use for our benefit, it seems somewhat noteworthy.

We needed to expose (aka, dig up) the entire discharge pipe at the pump station between #5 and #6.  As you can see in the picture below taken pre-dig, this 30 year old pipe developed a hole last year and currently has a repair clamp on it to prevent leaking.  However, after digging down to a 4' depth we found that we were below the irrigation pond's water level, and were fighting to keep the hole from filling up with water seeping in from the pond, which is only a few feet away.  

Instead of digging a huge hole and trying to continually pump muddy water out of it as the sides caved in, the simpler solution seemed to be to lower the pond's water level to a point that our hole would no longer be below it--water would now flow out of the hole to the pond, instead of into it from the pond.

With the surface area of the pond being close to five acres, we would have to remove 1.5 million gallons of water to lower the level by just one foot, and this doesn't account for ground water and rainfall that would be entering the pond as we tried to lower it.  

One option to get this much water moved would be to rent a pump, but pumps can have some downsides to using them.  First of all, they're often quite noisy, and if you want to get the water out quickly, then you're going to want to run the pump 24/7.  This takes us to another pump issue--they need to be fueled and maintained--especially if they're running around the clock.

Once again we opted for a simpler solution, which brings us back to our good old friend called gravity.  Instead of a pump, we used two siphons, made out of PVC pipe, to lower the water level.  They are silent, have no fuel cost, and you can basically "set them, and forget them."   

Pictured above is the smaller 2" siphon we used.  We fill it with water, gently place end caps on to keep the water in while setting in place.  As soon as we drop it onto the overflow, the end caps come off (but aren't lost, thanks to duct tape and string), and it starts sucking away.  The key here is that the bottom of the overflow structure is 6' lower than the top of it.

 

Based on the drop of the water level, we have averaged better than 150 gallons of water per minute using these siphons. We will now be able to continue digging around the discharge pipe, without having a muddy mess.  Thank you gravity!