What are stormwater

What are stormwater

Stormwaters are rainwater reaching the surface. Usually, stormwaters flowing into the sea or into water sources not suitable for use, thus being lost and rendered unavailable. Since floods are random events whose frequency and rate depend on the nature of the drainage basin, the rain intensity and its frequency, “Mekorot” invests great effort utilizing the stormwaters in the manner suited to their quality and their designation. Furthermore, the flood areas in Israel are geographically limited and the chances that conditions suited for floods will be formed are very low. Despite their low frequency and duration, floods are characterized by a relatively large volume of water reaching the ground in a relatively short period of time.

 

Flood characteristics in general and in Israel in particular, present a professional challenge to “Mekorot”: their gathering in areas prone to floods requires the availability of large accumulation areas for short periods of time. To overcome this challenge “Mekorot” channels the stormwaters to the suitable aquifers whose volume are almost unlimited, so they contain the water for a short time. Another challenge facing “Mekorot” is the need to take advantage of stormwaters in a manner that allows for continuous water supply throughout the year. To this end, the stormwaters are combined with other water sources such as effluent water and spring water, used primarily for agricultural irrigation. The floodwaters have an even more important role – the return of “debts” to Mother Nature: introducing water to the underground reservoirs contributes to their rehabilitation and to the rise of groundwater levels, after their state has significantly deteriorated following seven consecutive years of drought Israel has recently coped with.