House Project: The Water Tank

Okay, we spent Saturday afternoon fixing the various items that our builder can't seem to get around to fixing, like putting sealant where the exterior door frame casing has opened up a bit, then repainting. He did seem to make some progress on the interior doors that were still closing themselves, but it wasn't perfect. I spent some time bending hinge pins, and while they still aren't perfect, they are certainly good enough--any motion is very limited.

We had some interesting and not very useful conversations with various people about our brown water. My theory was that since the iron level was okay, the water is soft, and it tastes fine, that the problem was dirt in the water tank. Our well driller suggested that we talk to an acquaintance, who cleans out water tanks. This unfortunate person also has the first name of Clayton, so it was a more surreal conversation than usual, trying to leave a message from Clayton for Clayton with Clayton's wife (but not my wife). He was of the opinion that it would take a lot of mud in the water tank to cause this, and suggested that while he could clean the tank, that probably wasn't it.

So the next step was to talk to the company that sold me the lead filters, and the 5 micron and 1 micron filters that are upstream of the lead filters. They thought it might be iron (or perhaps manganese) in the water--although my iron levels were too low to explain this much brown. But they have a solution, the same one used by a lot of city water departments around here--polyphosphate injection (under pressure) to prevent the iron from coming out of solution.

Okay, before I spend another $600 to what is already beginning to look like a Rube Goldberg water system, we'll try and clean the water tank ourselves. So yesterday, we bought a 3.5 horsepower, 9 gallon Ridgid brand wet-dry shopvac. I picked the largest one that wasn't absurdly expensive--and that turned out to be, for reasons you will shortly read (unless you get bored), the largest size we could use.

We started a hose draining the water tank on Saturday afternoon. Yes, we could have just let the gravity-fed frost-free spigot empty the tank, but outlet for the tank is several inches above the bottom of the tank--meaning that even with the gravity-fed spigot, there would still be perhaps 50 to 75 gallons in the tank. We put the hose into the end of the shopvac's opening, and in a few seconds, the siphon was running.

One of the sources of dirt in the water tank was probably broken up material from when the well was drilled. The builder tells me, "Ordinarily, we run the well for a few thousand gallons before we hook it up to the house. We didn't in this case." Why, I asked? He couldn't figure out why.

Another potential source of dirt was rocks and dirt that could fall in through the top access port--which was opened and closed repeatedly during construction and testing of the water system, and which may still require some access occasionally. We needed some way to keep dirt out when this access port was open--but we couldn't clear all the dirt from the top, because the sunlight would promote algae growth (more about that later), and perhaps increase the risk of freezing the water in winter. So we hunted around at Home Depot, and found a 6" high by 24" diameter red brick tree ring--just 2" larger than the access port.

We get to the house after church today, and there is just a small amount of water left at the bottom of the tank. The shopvac sucks that up, and a lot of mud, in a big hurry. There is still a lot of stuff sticking to the walls and floors, and the shopvac just isn't pulling it out.

To my surprise, even though the port is less than 22" in diameter (and coincidentally, the exact diameter of the shopvac we bought), I can climb down inside. (My wife is claustrophobic, perhaps because of an incident when a neighbor boy locked her inside a chest when she was quite young, and left her there.)

Down I go--and pretty quickly I get the rest of the water and bulk mud--which is, curiously enough, the same disgusting brown as the water in the tub. The mud is actually a very fine clay, and sticks to the walls of the water tank far too well. By applying the end of the hose directly to the surface, I can remove most of the mud--as well as two dead insects (fortunately, above the water line), and lots of gravel and small rocks. At the far end of the tank, there is a small amount of algae on the walls--because the far end of the tank was partly exposed to sunlight. (We covered that up to prevent continued growth.)

The next step is to use a dropcloth to wipe down the interior. The tank is about four feet high, so I am sitting in the mud as I do this. (Yes, when it was all done, it looked like I had been very, very sick, and had not made it to the men's room in time.) This removes a bunch more silt and algae, but it still isn't quite as antiseptic as I would like.

The final step is to wipe down the walls with paper towels. I ran out before I reached the end, but 3/4 of the tank is now gleaming white plastic, with no mud, algae, or stains. The remainder is reasonably clean, although not perfect.

After I climbed out, we started up the well pump again. (It is started and stopped by a float sensor in the tank.) To my surprise, within about two hours, the tank has at least 600 gallons of water in it--and my, what a difference in color! Where it was too dark to see the bottom before, now I can see the bottom. The water is still a little yellow, but I'm hoping that the remaining silt will wash out over time.

I spent a bit of time figuring out how to get the pressurization pump running again. An air bubble in the line prevents the pump from pulling water, so you have to open a relief valve--and then close it again, real quick, before the air leaves, and water starts spurting out.

The water is still not absolutely clear, but it is close enough that I could take a bath in it--and it may take a few days for the old water in the water heater and the lines to completely flush. In addition, I have my suspicion that silt that was trapped in the 5 micron and 1 micron filters may be breaking off small fragments of silt that are still passing through. I will replace both filters shortly.

I suspect also that the silt has again clogged the lead filters, which might be why water pressure is again low. But since the last test results show that the water is now lead-free (even before going through the lead filter), perhaps I can just remove the lead filters, and improve flow.

The interior of the house is now done--a couple of spots where we are going use clear sealant in the bathrooms, but the house is now done and livable. The outside still needs to some trim painting and grading, but both of those are dependent on warm and dry weather--something that has been in short supply of late.