Rain on the Roof


Rain on the Roof Scottsdale Xeriscape Garden
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Q.   How much water pours off your rooftop each year?

a. 100 gallons      b. 2,000 gallons
c. 6,000 gallons      d. 10,000 gallons

A.   A house with a 1000-square-foot rooftop can collect 6000 gallons of waer during a year with 10 inches of rainfall..

Harvesting Rainwater
Hard surfaces of rooftops double as "catchment surfaces," collecting and directing rain with rain gutters and downspouts to water plants. Rainwater provides plants with a healthy drink of low-salt, nutrient-rich water.

Create natural looking depressions, called swales, near root systems. These shallow basins slow the flow of rainwater, allowing it to soak into the soil.

A House Is Like a Watershed

     Rooftop - mountain ridge         Downspouts - rivers
Rain gutters - valleys   Basins/swales - lakes and floodplain aquifers

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