When we bought our country home, one of the potential problem areas was the well. The inspector noted that there was a crack in the well cap, so he was concerned about coliform bacteria. This kind of surprised me, because I always thought that coli form bacteria came from, well, the other end of the food chute, if you know what I mean. Why would someone or something want to go around dropping stuff into my well?
As it turns out, all coliform is not created equal. Most of it is pretty harmless, and in fact most of us have some kinds of this stuff in our guts to help us digest food. But if there is any at all in your drinking water, there is contamination somewhere in the system. Coliform is pretty abundant in nature. A lot of insects carry it, which is one of the ways it can get into a well with a cracked cap.
Well, we tested the water and it was fine, but I still wanted to check out the cracked cap. It was cracked on the side where one of the set screws had been screwed too tight, but not on top. It’s the top that actually provides the seal, which is probably why we didn’t have coliform problems.
Our well has a separate conduit that runs outside the well casing and the electrical wires that run the pump come in through the wires and down the casing. Around the sides of the cap, there are set screws that hold the cap tight to the casing. When I took it off, there were a lot of spider nests and egg sacks, exactly the kind of thing that can result in a contaminated well. So I cleared them out.
But I also wanted to prevent critters from getting into the casing, and the simplest way to add a layer of protection is with window screen. I just cut a piece to size and fit it around the top of the casing before putting the cap back on. Nothing is a perfect preventative, but this gives a level of comfort that nothing too big is going to get into the casing.
To finish it off, I built a little house for it, using an old wooden box and some shingles I had left over from the roof. The well cap and casing is made to withstand plenty of weather for plenty of years, but a little extra protection can’t hurt, and since it’s right off the back deck it makes a conversation piece at least.
Because conditions change, if you have a well it makes sense to test your water every so often, and you can get a simple test kit through most State Departments of Environmental Quality or the equivalent agency. Contamination can come it at many points in the system, and can be caused by casing problems above or below the surface, aquifer contamination (especially if the well is too shallow), backflow problems or contaminated equipment during drilling or servicing a well.
If you can determine the source of contamination and correct it, then the contamination in the system has to be eliminated. This can be done through a process known as shock chlorination, which is basically introducing a lot of chlorine into the system to kill all the bad critters, then letting it sit for a couple of days and flushing it out so it doesn’t kill the good critters (meaning you).