Spring is here and Nepal temperatures are warming up quickly. This also means that the rains are starting to come. Already, Nepal has seen an abnormally rainy February, and March has also seen multiple rainstorms. Most people think that the monsoon is the only time to harvest rainwater, but if operated properly, rainwater harvesting systems can provide benefits during the Spring rainfall as well.
Here are some tips to optimize the use of your rainwater harvesting system during this season:
1) Operation of the First Flush – Since there are longer gaps between rainstorms in the Spring the first flush should be utilized and kept open during the first 10-15 minutes of the Spring rains. On days where it rains longer than 30 minutes for more than two days consecutively, then the first flush would not have to be used during the 2nd or 3rd days. However AFTER each rainstorm, the water stored in the first flush pipe, should be emptied to avoid contamination in the future.
2) SmartPaani Rapid Sand Filter – This should be cleaned once before the Spring rains and monitored throughout. Since there are longer gaps between rains, dust and dirt accumulate more on the rooftops and not all is removed by the first flush. Monitoring and maintaining the rapid sand filter by occasionally removing and washing the top layers of sand is the best way to ensure the system functions properly. SmartPaani technicians are available to provide this service as well.
3) Catchments – Keep your rooftop as clean as possible, clean it once between rainstorms (sweeping) if you can. If you have a surface harvesting system clean this along with the recharge device to prevent blockages and overflow during this period.
Why are Spring rains beneficial? Most people think that it is only during the monsoon that rainwater harvesting is beneficial, however what they don’t realize is that the average rainfall from March-June is the equivalent of around 45,000 liters on a standard household’s roof. Many of our customers come back to us happily saying that because of the rain in the “dry” season they did not have to buy tankers. While it won’t completely solve household’s water problems during this time, it will help significantly.