Pond Boss Forums INTRO Questions & Observations How do you drain a pond?

Several ways to skin that cat. The decision will somewhat hinge on the reason you are draining it. Cutting the dam is partially effective, but then you have a dam to repair. If you are simply going to deepen a small pond, siphoning or pumping could be the best option.
Remember, most ponds have an area which sits below natural ground level..the area where dirt was borrowed to build the original dam. It's called the "borrow pit." Water won't flow out of there by itself. It needs help, so you will be pumping anyway.
If you intend to do peripheral work, siphon over the top of the dam with 4-8" PVC, do the work, and let the pond refill. Run your pipe, with a one way foot, inside the pond, as far down as you can. Bring it up your dam, then over the top. At the top, install a valve, choked down to garden hose size. Then, run the pipe down the backside of your dam, all the way to the bottom. Install a cap, or a valve...depending how much money you wish to spend (or if you want to permanently install the siphon at some point) Close the backside valve, then fill the pipe with water via the small garden hose size valve. Close that valve, open the big one, and water will flow. Now...you can also use small flexible hose by getting into the pond,(one end of your hose taped shut), fill the hose, cap the other end, then drag it over the top of your dam (with a friend), then open each end at the same time.
That's a cheaper way.