Rainwater catchment systems conference in KMC

[Les C]

Starting tomorrow, 8/15, the American Rainwater Catchment Systems Association (ARCSA) is holding their annual conference at Kilauea Military Camp for 3 days. The Hawai'i Rainwater Catchment Systems Association (HRCS) is hosting.

On Thursday night, 8/16, there will be a community dinner from 5:00p to 8:30p at Kea'au High School. Cost is $10/person. This is a great chance to learn more about catchment systems. There will be a panel discussion of national rainwater catchment experts. The Rotary Clubs of East Hawai'i is sponsoring the dinner. It's also being called a trade show, so I expect that there will be displays. Come learn about water collection and treatment, and find out about new ideas for systems. Find out what's going on in the world of catchment outside of Hawaii. They may have copies of the new, free HRCS Services Directory, a list of water catchment service providers, suppliers, and maintainers in the county.

The HRCS has a website
http://www.hawaiirain.org
And the group has memberships, if you'd like to be a part of the rainwater catchment braintrust on the Island. The site is still growing and there's more to come, but you can download PDFs of the services directory and Trisha Macomber's guidelines (the blue catchment book) now from the Resources/Downloads page.

The University is also developing a related water catchment site:
http://www.ctahr.hawaii.edu/rainwater
It wasn't launched yet when I just checked.

[Les C]

The community dinner/trade show at Kea'au High School last night was quite an event. The best part was the Q&A for the expert panel. The panel was composed of participants in the ARCSA conference and were represented by engineers, chemists, municipal system managers, and a timber tank refurbisher. Despite all of this brainpower, it became very clear that rainwater catchment knowledge for the home is still in development. No one seemed to have all of the answers. One woman asked, "When do I change my filters?" And there was no clear answer. There was a lot of knowledge available, make no mistake about that, there's just no one answer for every one. Some tidbits:

- The guy from Pahoa Propane & Battery had a lot of experiential stuff to share, like slime on some customers' filters (pollen?), using a diverter to exclude water that might have been subject to more sulfur dioxide emissions (vog), and differing filter replacement regimen for different customers.

- There's another water tester who lives in HPP and has his office in Hilo, Pololei Labs, 938-0560. Bob Betts of Bob's Catchment Testing in Kea'au, 936-3426, was not present.

- There was an option for mosquito control that didn't involve chemicals. There was a pool product that involved some kind of insect/organism that was supposed to be effective with algae. I think I may have come across this on the web; it involves a sphere that contains the "active ingredients" that you place in your tank.

- having the proper pH level for your water was emphasized because of the corrosive effect it can have on copper plumbing. [I've seen copper pipes in a home in HPP with pinhole leaks that were making a mess of the interior of the bathroom walls.] One possible treatment mentioned was the placement of limestone chunks in the system to neutralize the sulfuric acid. Of course, it was pointed out that limestone is not available here; coral (available in Kona) was suggested as a good substitute. But Trish Macomber pointed out that she heard that this doesn't work in Hawai'i because the reaction of the limestone and acid forms an insoluble surface on the limestone that stops its effectiveness. The same may happen with coral.

- There were some interesting gizmos on display, some were claimed to have been made by people in the community. Actually, I only saw a couple of floating intakes that might come under the homemade description. There was an interesting leaf diverter that I've seen literature for at Waterworks.

- There were representatives from Sri Lanka, Australia, New Zealand, as well as Texas and Ohio. Apparently, the only place that has government regulations for drinkable rainwater by way of catchment is Sri Lanka.

HRCS is planning more community events. If you have catchment and care about your water quality, I encourage you to join HRCS and help to make it a stronger organization. You can get information on becoming a member at the website in the previous post.

Edited by - Les C on 08/17/2007 20:18:38

[Scott_S]

Sounds like an interesting night, thanks for sharing Les. Did anyone have a simple drop leg with a floating device in it?

Scott

[Kelena]

Thanks, Les. Sorry I couldn't make it. Was there any discussion about whether a different pipe material, such as PVC, might be more appropriate? In other words, are copper pipes to be avoided? I did notice corrosion on the pipes of one house that I looked at back in December.

[Les C]

quote:

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Did anyone have a simple drop leg with a floating device in it?

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Scott, I don't quite understand what you mean. Are you talking about a tank water intake? Can you expand on the idea?

quote:

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Was there any discussion about whether a different pipe material, such as PVC, might be more appropriate? In other words, are copper pipes to be avoided?

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Glen, no, but that may be a good discussion to have. Changing your plumbing from one material to another could be very costly. The way to deal with it was to monitor the pH of your water and correct it when necessary. Ferro-cement tanks will neutralize acid content because of the basic nature (as in acid vs. base) of the material. In a non-ferro-cement tank, suggested treatments were to mix up solutions of baking soda to add to your tank. Automating this was not considered good because the pH is not constant; and making an acidic (low pH) tank of water more basic (high pH) was easier than making a basic level more acidic. There's something about it taking more correction to go in the other direction, so you don't want to keep your pH elevated. Too basic has its own problems.

[Scott_S]

Some time ago on the web I seen this device for sale, it include a floating ball and a valve. You tee off between the tank and the gutter install this and a drop leg as long as you want. The drop leg has a hole in it to let it drain slowly. The idea was to catch the first run off, the ball floats up to seal the drop leg, and later the drop leg drains off. I will search the web again to see if I can find it.

first flush system-duh:

http://www.rainharvesting.com.au/first_f...erters.asp

Scott

Edited by - scott_s on 08/19/2007 04:05:52

[Kelena]

Thanks, Les. I have a cement tank, but I do not know if it is ferro-cement. It is underground, which is pretty strange (not that I mind). Seems like an underground tank could have its own problems though. I was thinking of when you rinse of the patio.....well the tank is underneath the patio! So, I guess you would be rinsing toe jam into your tank!

I hope they have this conference again. I got the materials for the ARCSA but did not join. Is it worthwhile to join?

[Carey]

Glen, our last (rental) house had an underground catchment. Doesn't yours have a slight raised lip around the inspection port to keep out the toe jam? if not, it probably would not be hard to put in a slightly raised curb for toe jam.

[Kelena]

I wish I knew! I was in the house I bought for about ten minutes. At the time, it did not appear that there was anyway I would be in line to get it (there was an accepted offer on the houes). If I recall, the catchment may actually be sealed. That is, it is below the patio and there is a hatch that you lift up. If I recall, the hatch has some sort of lip, or gasket or something, so you are right. And certainly one could be installed. Hope you get a chance to come by while we are in the neighborhood.

[Les C]

Scott, I think I've heard about something like what you described. I recall reading that there was a problem in that it was easy for the drain hole to become plugged.

Glen, a cement or ferro-cement tank would probably both have water in direct contact with the cement which would neutralize acid rain. The "ferro" part of a ferro-cement tank I believe refers to the iron rebar in the cement that provides strength to the structure which is important because of our earthquakes. A cement block tank w/o rebar reinforcement or a poured cement structure w/o reinforcement (hard to imagine anyone building one like this) are problematic where earthquakes are prevalent. I think Trisha Macomber's guide notes that cement block tanks may be more susceptible to leaking than a ferro-cement tank. I think Rob knows about ferro-cement tanks and can probably provide good information.

I don't know if ARCSA, the national organization, is worth joining. I believe that the local organization, HRCS, is worth joining, if only to provide our local group with your input and for you to get locally applicable information. The conference was for industry professionals. The community dinner was an opportunity to have the gathered experts available to discuss systems and answer questions from users. HRCS is planning to have community seminars in various places. Becoming a member of the org. is a good way to provide input to have a seminar held in your community.

Edited by - Les C on 08/20/2007 22:04:49