oy! this topic again in my life, but I'm hoping this time to nail it and in the future be able to answer all questions about it succinctly:

someone says to me: "you can't harvest rainwater! that's illegal by washington state law. and even if they turn a blind eye to it now, if they ever want to fine you in the future..."

yes, people collect rainwater everywhere, and yes the city of seattle even catches it to flush toilets. what do i tell the person with the quote above??? what exactly is the state law? do cities or counties just opt out of it?

Doesn't the city of Seattle have programs to teach people how to do this?  If the city is advocating it, it seems that it cannot be contrary to state law.

I know that in colorado, there are areas where it is not permitted.  The rain drops that land on your roof are somebody else's property. 

Yes the city of seattle teaches people how to harvest, Yes it's contrary to state law. Thus the reason for asking the question!

Why is that illegal; mosquito control?

Water rights.

Suppose somebody moves to colorado in 1895 and buys a million acres or dry land.  Then they sell off chunks, but they say "I'm selling you the land, but not the water that falls on the land - because that water flows downstream to where I have an ag thing going on."

Sometimes governments do something similar because they are trying to put together enough water for people in cities. 

It starts to get really wacky.  But in the end, there are places where you are not allowed to capture the water that runs off of your roof.

I found this page on rainwater catchment in the seattle area.  There is an email address at the bottom of the page and I sent an email asking about legality in washington state.  Let's see what happens ...

And here is the first response:

"Hi Paul, I've heard about this before too, but am not familiar enough
with the legalities of rainwater harvesting and practical legal
application o to be shed any light on the subject.  I'm cc'ing a few of
our staff who may know more on the subject.  Thanks for visiting the
Water and Land Resources' Web site."

Paul,
I am really looking forward to seeing the answer you get from the staff.
You would think  the question would have been given to someone who was at least a little more familiar
with the subject...

I just received two emails from Greg Rabourn at king county:

------------

Hi Paul,
Sorry about my delay in responding. I have been out. It was never the
intent of the law to cover rain barrels.  They have resolved this issue
and residential scale collection is not illegal. Feel free to start
collecting.

------------

A slight clarification, some legal jurisdictions are going ahead and
getting an official water right from Ecology just to remove any doubt
people might have about the legal status of having a rain barrel. City
of Seattle is one example.

I've never heard of any legal issues with rain barrels before.  My problem with them has always been that they collect water off of toxic roof materials.
Many roofs are made of asphalt shingle which as we know are made of petrol products we shouldn't eat.  Lots of roofs have lead flashing in some areas.  Roofs have aluminum flashing and copper flashing and sometimes all three along with toxic calking materials and roofing tar itself.

I know rain barrels conserve water, keep the well from running dry and lower your water bill if you live in the water district and get your water pumped from the city but I wouldn't use one for anything but maybe washing a vehicle maybe or if it was the only water I had perhaps.
I've also seen them rot the corner boards and siding off of people's house due to all that moisture being kept so close to the building, especially on the less well lit parts of the house.

More from king county:  http://www.seattle.gov/dpd/news/20080401a.asp

It sounds like seattle might be an exception to some vague laws for the state.

If a person were really interesting in collecting rainwater and had a few extra dollars, the simplest thing to do would be to collect some clean (after the first hour of rain, say) water and take it in to some lab that specializes in rainwater.  First, ask them how to collect it properly (they may want it in glass, which is quite stable). Then tell them your worries and ask them to test it for the things your roof/area is likely to be contaminating the water.

You could call your local Cooperative Extension Service office (see http://www.csrees.usda.gov/Extension/) or look in your phone book under Water Analysis & Testing.

All the guessing and worrying in the world isn't going to give you the answers you want.

Also keep in mind that rainwater is twenty times more pure than the purest groundwater.

Sue

Yikes!

I guess it all depends on where you live. Here in New Mexico not only is it legal, it's encouraged and the city I live in has a rain barrel rebate program. I'm just using the harvested rain water for the garden at this point. But, with some more storage capacity I could consider other uses.

Putting in rain barrels was pretty easy for me, the big hold up was getting a new roof first. http://www.econewmexico.com/rain-barrel-water-harvesting

Tim

Looks like this is getting better for people who want to collect rainwater. Hopefully it will catch on nationwide.

http://www.nytimes.com/2009/06/29/us/29rain.html?_r=0