Water Collection - Operation

The first water to come off the roof after a dry spell (the most recent spell lasted six weeks) is very dirty. It contains dust, bird droppings, and debris blown in from trees. So I have a clarifier. This clarifier is a vertical 4" diameter tube. The first water from the roof goes into this tube, raising a green plastic ball. When the ball gets to the top of the tube it closes off the entry and the remaining water — hopefully now clean — flows into the storage tanks.At the bottom of the tube is a plastic filter and a rubber disk with a small hole, that eventually drains the tube so that it can catch the dirty water after the next dry spell.

I am learning that I must clean the filter after each rain spell — or the tube will not drain and the next batch of dirty water will flow into my tanks. Not only that, but the dirty water in the clarifier tube stinks really badly.

Of course, a really hard rain (such as we had recently) will wash more off the roof than just dust. The stucco on my house (and the inside of the parapet walls around the roof), consists of Portland cement filled with sand. Some of the sand grains are not firmly adhered, and fall off, collecting on the roof surface. When a heavy rain washes these off the roof, the sand collects in my clarifier, plugging the drain.

This is more grit than I can remove from the clarifier than by simply removing the black cap and the narrow plastic filter. I must remove the white 4” cap. If the clarifier tube is full of water, three gallons comes roaring out all at once. Thus I keep a plastic trash bin under the clarifier, and must dump this bin full of dirty, stinky water, into the nearby utility sink. Of course some gets onto the garage floor, but this is not a disaster.

After three practice sessions (two light rains and a gully-washer) I think I have learned how to maintain my clarifier. We had a gentle rain last night. The roof is now fairly clean, and the clarifier worked as planned. We shall see how well I remember to clean the filter after every rain — especially when we have the next dry spell.