Pre-filtering Rain Water

Keep your Rainwater tank clean this summer!

Usually, during the long dry winter we install water storage tanks and fill them with grey water. If you did this you will probably know that the grey water goes straight into the tank, free of major debris. Well, this is about to change.

Particularly because of the lack of rain; roofs, gutters and downpipes have collected a lot of trash during the winter. Soil, weather-beaten roof tiles, leaves and bird droppings can clog pumps, valves, and pipes. If these solids get into the tank, they will settle on the floor and cause damage, as well as reduce available storage capacity. Since spring is the season for a lot of rain after the long dry winter, we must remember to prepare our tanks to accomodate it's water.  

Pre-filtering rainwater is a simple, but effective way to keep your water tanks clean. There are several options available and choice will depend on price and practicality.

Here are a few inexpensive DIY examples.

  • The First Flush Diverter catches the first runoff with all the debris in a separate section of the downpipe until it is full. Clean water then flows into the tank. The First Flush Diverter system is effective in summer and rainfall areas where the dry winter season is followed by frequent and intense downpours. There are a number of First Flush Diverters available to accommodate the variation in gutters and downpipe sizes.
  • A Basket Filter is inserted in the tank below the filter pipe. It has a large screened basket that is placed inside a plastic housing. The water flows through the filter and out of a lower spout. There are various sizes of basket filters available to cope with small to very large roof areas. The basket is easily accessible to clean the filter.
  • The Leaf Catcher Filter can be mounted directly under the roof gutter, on top of the downpipe, or mid-mounted by splitting the downpipe. The latter method will make filter cleaning an easier exercise. 
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