Rainwater Collection From Roof Laws

Two laws were passed in 2009 which loosened restrictions on rainwater collection allowing residents to use rainwater for non potable purposes.

Rainwater collection from roof laws.

That s because weirdly collecting rainwater is actually illegal in some states. Rainwater collection calculation formulas and equations roof area ft2 x precipitation amount in x 0 623 amount collected gallons easy formula to remember. There are regulations about the use of harvested roof water but it is not against the law do do so. In 2009 we issued a rainwater use interpretive policy which clarifies that you may use water collected from your rooftop without a water right permit.

Though these collection system permits do not limit the size of the rain barrel the water must be collected from the roof of the primary residence and the rainwater may only be used for the uses allowed under the resident s exempt well permit. Water rights are a first in time first in right situation. Storage tanks can be inside or outside above or below ground or partially above and partially below ground see fi gures 1 and 2. However there are rules on using rainwater as a potable drinkable water source.

1 of rain on 1 000 sf roof will yield 623 gallons roof area m2 x precipitation amount mm amount collected liters. Rainwater collection or rainwater catchment are other terms used to refer to this practice. Rainwater collection including the use of rain barrels has become more popular as a supplemental source of water. There are however very strict laws regarding ground water and surface water.

Collected rainwater may be used to irrigate outdoor lawns plants or gardens. In 2016 house bill 16 1005 was passed allowing residents to collect rainwater from a catchment system on their rooftops into two rain barrels with a combined capacity of 110 gallons. To comply with colorado water law the container must be equipped with a sealable lid. State legislatures consider factors such as water rights quality standards and public health that rainwater harvesting may impact.

A basic rainwater collection system includes a roof gutters or roof drains and a piping system to convey the water to and from a storage tank or cistern. Untreated rainwater collected from roofs is not safe to drink. Exactly how much rainwater you re allowed to collect and use varies across the u s for example under a colorado law passed in 2016 homeowners are now allowed to catch and use two rain barrels a total of 110 gallons from their rooftops but no more. A journal published by the university of north carolina titled rainwater collection water law and climate change.