Question
QUESTION: Is there a way to rid our man made swimming pond of leeches, or blood suckers?  I usually only find one on me every other time I go in the pond( we have fish), but yesterday I put on a pair of water sandals that I left outside and think that though they were mostly dry--when I wore them in the pond, upon exiting it and taking sandals off my right foot was covered with tiny suckers.  A big balled up black one rolled out from under my big toe.  Is it possible they had a nest in my sandal or did I step into one in the shallow water?

ANSWER: Leaches can be got rid with the write up below.
I do not think the leaches have a nest in the sandal it might have caught up when you entered the pool.
Anyways if you still worried wash your sandal with pool acid.

The best I have come across is on Squidoo and which was successful it is as follows:
(http://www.squidoo.com/how-to-remove-leeches-from-your-pond-without-chemicals)
The Search For Safe Leech Control
Avoiding Dangerous Chemicals.
Hmmmm.... how to kill leeches in pond..... If you want to go down the chemical route it is complex and dangerous. It is also expensive to buy pond chemicals in the quantities needed. It involves replacing all plants, estimating exactly how much water the pond holds, mixing chemicals that could possibly harm the smaller fish - and destroying every living invertebrate in the pond. That was not something we were prepared to consider. So what is safe to use to kill leaches? I searched and searched until I found the idea of constructing a leech trap out of a coffee tin. Here coffee tins are not so easy to find, they tend to be metallic cardboard. Then I thought of fresh soup containers and the leech trap was born.

At present we are on our third trap and numbers are reducing. I was horrified at the number of leeches in the last trap.... How you dispose of them having caught them is another issue of course, but you need to remember that leeches are dangerous, but they are also living animals with a nervous system and should be disposed of humanely. Freezing them is one method, or release into a river system, if it is permitted, where larger fish may eat them.
Making the holes in the leech trap
Boring from the outside of the leech trap
Boring holes to make a leech trap

Boring holes from the outside to create a burr on the leech trap makes it less likely leeches will crawl out through the holes. These holes can be made carefully with a steak knife and should vary in size from 2-5mm.
Raw Materials for the Leech Trap
And how the Leech Trap works
The leech trap baited with kidney.

The leech trap works on the same principle as Winnie the Pooh and the Honey Jar. Leeches, being greedy, will gorge on blood and when they do they become so big that they get stuck in the hole. That is the principle - and it works. The main items needed are meat and a container. Liver or kidney is cheap and works well. Here you see a view of the inside of the leech trap. The holes are also burred which discourages early escape.
Sinking the leech trap
Placing the leech trap in your pond
Leech trap Floating in the Pond

Just use a net to lower the trap into the water. It will fill with water and float upright. This will catch many leeches as they can sense the meat and swim up to it. To sink the trap deeper, put stones in before the meat. Then just leave the trap for a few days to a week. It will soon fill if you have a bad infestation.


---------- FOLLOW-UP ----------

QUESTION: 1) where do they nest?... so I can scoop them out and put elsewhere  without using chemicals.  2) Why do you say they are dangerous?

Answer
Okay yes,you scoop them out and put elsewhere but they are no problems when they in the pool.
But once in contact with a living creature it sucks blood which is dangerous.
In some Asian medicines leeches are used to such bad blood from moles on the body.