 rain barrels rain barrels water conservation what you should know if you live in the portland metro area it s true that it rains a lot in the pacific northwest but unlike other parts of the country that receive rainfall yearround here in the portland metro area we typically receive the least amount of rainfall during the summer months a time of year when our outdoor water usage is at its highest the portland metro area gets about 37 inches of rainfall annually and typically we receive about 90 of that rainfall from october to may a time of year when we don t need extra water to irrigate our gardens or lawns because of this seasonal rainfall pattern and their limited storage capacity rain barrels are not the most effective water conservation method for our region a typical rain barrel holds about 55 gallons  this may initially seem like a lot of water but take a moment to consider your landscape s water needs and you may find that it will take far more rain barrels to water your landscape than you initially thought we recommend watering an established lawn about 1 inch of water each week a bit more in hot dry weather so if you have a 100 square foot patch of lawn you will need about 62 gallons a week to water the recommended 1 inch assuming you will water this grass from mayseptember you will need to collect at least 1300 gallons of water that translates to about 24 rain barrels and while this seems like a lot of water it may actually only be a fraction of the water that will run off your roof and through your downspouts in a typical year  for example a roof with a 1000 square foot area will yield about 620 gallons of water in a 1 inch rain event enough to fill a 55 gallon rain barrel 11 times considering our annual rainfall that roof could yield more than 417 rain barrels each year  so now what  if your original goal for installing a rain barrel or two was to conserve water don t despair though rain barrels are not the most effective conservation method they will help save some water we also recommend checking out some more effective water conservation alternatives such as installing sprinkler controllers and rain sensors or using a hose with a shutoff nozzle you can find out about these and other water conservation tips under the  outdoor and  indoor sections of this website  rain barrel faqs what is a rain barrel  rain barrels are containers that divert and collect rain water that otherwise would flow off a roof through gutters and downspouts and become runoff water captured in rain barrels is typically used for outdoor irrigation purposes rain barrels come in a wide variety of materials plastic and wood are the most common designs and colors common sizes for residential use are 55 to 90 gallons prices range from about 50 for doityourself kits and up to several hundred dollars for readymade rain barrels a quick internet search of rain barrels will bring up numerous informative sites and retailers we have also developed resources section on the back of this brochure to get you started will i save money on water by installing a rain barrel  in short no here in the greater portland metro area we are fortunate to have relatively inexpensive water  check your water bill for actual cost many providers combine water and sewer costs on the same bill so be sure you are looking at the water section only  once you know the cost of your water you can figure out how long it will take you to recoup the cost of the rain barrel  for example let s say you have a 55 gallon rain barrel that cost you 90 if your water provider charges 197 per ccf you would save an average of 14 each time the rain barrel filled using this example you would have to fill the rain barrel 643 times just to break even on the cost of the barrel at a rate of emptying and filling the barrel 50 times a year it would take almost 13 years to make your money back most water providers measure water in ccf one ccf represents 100 cubic feet or 748 gallons of water check your bill for the rate your provider charges per ccf  beyond the initial cost for the rain barrel there are additional maintenance costs that should be considered where can collected rain water be used  collected rain water is commonly used for exterior nonpotable purposes such as irrigation typically no permit is required for irrigation use however be sure to check local codes and ordinances on the use of rain barrels before you do any disconnections or alterations to your property there are differing opinions about using water from a rain barrel on edible plants such as vegetables fruits or herbs be sure to do some research to determine what option is right for you what should i do with the rainwater i can t collect  a typical 55gallon rain barrel will capture only a fraction of roof runoff so be sure to include an option for overflow into your plan some rain barrels are set up to divert excess water into another rain barrel or back into the storm drain once they are full another option is to send your overflow into your yard making sure that it drains away from your foundation to a safe discharge location rain gardens are also becoming a popular way to incorporate rainwater runoff into your landscape see the resources section on the back of this brochure for more info  resources a quick internet search of rain barrels will bring up numerous informative sites and retailers here are a few more to get you started overviews  http wwwportlandonlinecom shared cfm imagecfm id 182095 http wwwsavingwaterorg docs rainbarrelspdf tutorials  http wwwgeocitiescom rainsystem howtohtml   http wwwnwrenovationcom 21rainbarrelhtml rain gardens  http wwworegonmetrogov indexcfm go byweb id 25102  rain barrels rain barrels   outdoor  