water catchment

[SouthKona]

we are getting ready to put in a water catchment system. any hints ("I wish i'd known that BEFORE i put in my system" sort of thing)? recommendations on size of tank, type of tank, filtration? thanks.

[jdub]

As far as the size of your tank and filtration options, I'd check with whatever municipl authority applies to your location (I'm not sure what that is in your area of SouthKona). Projected consumption, possible airborne pathogens, chlorine maintenance, pumping options and St DOH requirements are all pertinent to your choice. Retro-fitting is complicated and hopelessly costly, so ask a lot of questions of whatever authorities or contractors you speak with about yout catchment system.

[kimo55]

we are getting ready to put in a water catchment system. any hints ("I wish i'd known that BEFORE i put in my system" sort of thing)? recommendations on size of tank, type of tank, filtration? thanks.

maybe...

http://water.usgs.gov/wrri/97grants/gu97sei2.htm

http://www.ctahr.hawaii.edu/ctahr2001/CTAHRInAction/Feb_02/TMacomber.html

http://westhawaiitoday.com/articles/2005/06/02/features/features03.txt
bobco
vinnie
for access

[SouthKona]

thanks for the tips. and, join me in wishing for year round rain. :)

[craigwatanabe]

The most important aspect of any new catchment system is if it will be used for potable water catchment.

If yes, then make sure you don't use galvanized nails or screws. In any case make sure if using fasteners of different metals to use the neoprene or Neo nails to isolate one metal from the other.

In areas where there is a little rain certain times of the year, consider using a diverter. This device will allow the initial rain to wash the roof clean and send this initial flow of water down the downspout. Depending on the type of diverter, it will eventually stop allowing the runoff to be diverted to the catchent tank.

Don't consider using a catchment system if there are trees nearby where the leaves can contaminate the water supply or overhanging trees where rats can get onto your roof and urinate.

Don't go the cheap method. Some people like to use those free-standing vinyl swimming pools because it's large size, filtering system and relatively low-cost ($700 on up) seems like a nice bargain for what you get. Vinyl pools when left in the sun to heat up with water in it will leach out harmful and cancerous PVCs into the water system. You've tasted it before when you drink water from a water hose left in the sun, it has that chemical taste.

According to water haulers, some of the better catchment tanks include fiberglass and metal "doughboys" with metal tops and can last around 10-years.

For a family of four, consider a 10,000 gallon tank and with no rain, expect to fill it roughly every 6-weeks at $75 to $85 per 4,000 gallons delivered.

You can use a shallow-well pump to keep your plumbing pressurized at a nice 40-psi. I use a carbon filter just after the pump trapping down to 1-micron of particulates and odor (if any). At the kitchen you can use a reverse osmosis or UV filtering system if you want absolute biologically pure water. Otherwise standard carbon filtering like those used on refrigerators or faucet mounted units like PUR is sufficient for clean and potable water.

On the shower heads use flow restrictors to maintain positive water pressure throughout the system. And make sure on all of your water spigots/bibs to attach checkvalves to keep your catchment tanks free from backflow.

[cezanne]

On the Big Island, is a water catchment system an alternative or a supplement to tapping into a water main, or do you have no choice but to install one? :confused:

[kimo55]

On the Big Island, is a water catchment system an alternative or a supplement to tapping into a water main, or do you have no choice but to install one? :confused:

depends on the exact area.
some no choice but catchment.
other areas, a financial necessity as a supplement

[Miulang]

In the hinterlands where Craig lives (Keeau/Puna), I think you have to have a catchment system if you want water. No water lines and probably no sewers out in that part of the world yet, either, until there are more people and then there might be a requirement for water lines and sewer systems. At that point the real estate values will really skyrocket. When you get city amenities (like residential home delivery of the mail, water and sewer lines) is when your taxes start to go up. But if you got the pioneering spirit like Craig, it's a great opportunity to get a relatively good deal on a house, compared to Kona or on Oahu, Kauai or Maui.

Miulang

[cezanne]

Oh OK thanks... :)

[DaveNSoKona]

My 2 cents...

The people that built our house used asphalt shingles, which pretty much excludes catchment from the roof area from being used as drinking water. You really get used to it over time. If it doesn't rain there are several water haulers in Kau and South Kona. Make sure that your tank placement is accessible to a fairly large truck in case it stops raining for a while. There is a calculation for the size of the tank depending on your catchment area, rainfall etc. My advice is to get the largest one you can afford. We have an 18K tank for each house. The building inspector said you need engineering (permit) if its over 5' or 6' tall. Most of the tanks here are made of corrugated sheet metal with a plastic liner. We have replaced one liner in the five years we have lived here but the other liner has been fine for 10+ years. Consider a cover that is supported above the water if you don't want to watch birds bathing in your tank. This involves metal poles above your tank and is a bitch to install (3 people min.)

If you want you can come by and look at ours in South Kona.

[craigwatanabe]

In the hinterlands where Craig lives (Keeau/Puna), I think you have to have a catchment system if you want water. No water lines and probably no sewers out in that part of the world yet, either, until there are more people and then there might be a requirement for water lines and sewer systems. At that point the real estate values will really skyrocket. When you get city amenities (like residential home delivery of the mail, water and sewer lines) is when your taxes start to go up. But if you got the pioneering spirit like Craig, it's a great opportunity to get a relatively good deal on a house, compared to Kona or on Oahu, Kauai or Maui.

Miulang


The lack of county water hasn't detered housing prices in Keaau down by the ocean.

As a matter of fact, home prices are higher in my area that's closer to the ocean than other properties that are closer to the highway or in Hilo where county waterlines are commonplace.

To me having a catchment system is the better way to go. It makes you more aware of water conservation and the water (in my area) is sweeter than county water, it's also softer.

As for pioneering Miulang...my area is building up so fast that I've got neighbors up and down my road where just two years ago there was nothing but empty lots with lots of tall grass and wild bamboo orchids growing everywhere.

There's a new home coming up almost every month and the sound of bulldozers clearing lots and cement trucks everyday is making this area look like suburbia. It's amazing! It's not so rural anymore. :(

[SouthKona]

thanks for all the info. it sounds confusing, but then again, im used to just turning on the faucet and: whosh, water. re: tank placement, and the comment to make it accessible to the water truck, please tell me that they have a long hose they can use to get to the tank?! maybe i need a water truck to visit our site before we put in the tank. we've got plans for the house to be between the end of the driveway and the water tank...... :eek:

by the way, least everyone think that the county supplies water to the developed areas of the island, did you know that waikoloa has to buy its water from a private company. waikoloa pays some of the highest taxes, yet does not have county water.

and no, i'm not putting in a catchment system in waikoloa.

[DaveNSoKona]

Here is my tank with cover and overflow valve:

http://www.konamist.info/gallery/albums/kona_farm/catchment.sized.jpg

The below pic tries to show that a 6000 gal water truck (full size over-the-road semi type truck) can navigate down a 450 foot grass driveway if it is straight and flat enough and pump water 20-(40?) feet from there.

http://www.konamist.info/gallery/albums/kona_farm/catchment2.sized.jpg

FYI - I have seen water trucks hooked up to pipes on the highway with no tank in sight.

[SouthKona]

thanks, davensokona, for the pics. you brought up an interesting thought, maybe one just has to put in a pipe from the water tank to the location where the water truck will park. i suppose my husband already knows what he wants to do, humm, maybe i need to ask him what he has planned.
you must live on the "wet side" of so.kona, 'cuz your pics show a lot more green grass than anywhere around MY part of so.kona! i thought only waimea had a "wet side" and "dry side".... :)

[DaveNSoKona]

I don't know about wet/dry sides of Kona but I failed to mention that we haven't had to buy/haul water in a year and a half. We are mauka of highway of Milolii and most of the farms in South Kona in-between Kipahoehoe and Manuka Natural Reserves above 1500 feet elevation look like this. (not being on a recent lava flow helps too) We are also close to the recent Nature Conservancy acquisition in Honomalino of 4000 acres.

Being near so many big trees helps with getting more rain caused by mauka/trades afternoon showers. Big trees tend to attract more rain for some reason.

[craigwatanabe]

it's not that big trees attract more rain, its more that rain makes for big trees. Trees are not good for catchment systems as the leaves fall onto the roofs and the decomposing leaves end up tainting your water like tea leaves.

Tanks like Dave's is a good type of tank as the costs are lower than mine (one piece fiberglass enclosed tanks...meaning no separate top covers but a manhole for periodic inspection/cleaning and filling)

If your tank is over 6-feet high then a permit is necessary that's why the doughboys are a popular choice. They look like Dave's but they are under 6-feet high and have a wider diameter to compensate for the volume. The problem with these low-profile tanks is the canvas cover is bigger and is harder to keep erect because of it's larger surface area.

As for running out of water. That's a common fear for most newbies, I know I was one of them. But with rain falling virtually every evening (a lot of time intense) your tank(s) get topped off every night.

During the drought season you just schedule the water hauler to deliver at a rate of one delivery every three weeks if you are a heavy user or once a month if you conserve or are a small family (under 4).

You mentioned long hoses. Water haulers don't like to unreel all their hose and accessability is also something they like. One water hauler told me they cringe and will sometimes put homes that have difficult tank locations last on their list of deliveries focusing on the easier homes. Makes sense as for every house the tanker has to take it's time to get to the tank, that's less time to pump or get to another home.

Another way to get on their (water hauler's) favorable customer list is to periodically take a delivery during non-drought times. When it rains heavily most of the year, these haulers don't bring in a whole lot of revenue and they suffer. By taking a token delivery during these times they remember you when everybody's calling for water when it's dry time. I learned that back scratcher this year when I took two loads during the rainy season because SOMEONE LEFT THE RUNNING TOILET GO FOR TWO DAYS!!! and drained both 5,000 gallon tanks to within 1/8-tank. Talk about sucking up vapors!

When the drought hit last month, I called this hauler and got two deliveries within two hours instead of one week.

Once you get used to catchment systems, it's hard to wonder why you never used it before when you were on county water paying high sewer fees to boot!

[SouthKona]

just wondering, if you were to need to buy a tank again, would you choose a fiberglass or a metal w/ liner? and, i saw mention of "both 5,000 gal" tanks ... i won't need TWO tanks will i? and, why two 5,000 gal instead of one 10,000 gal (maybe they don't make 10,000 gal...?)?
i'm mostly worried that we will buy a setup that needs improvements in the future, and that we could have avoided problems/expense by buying the right thing in the first place. that applies to not only the tank itself, but also the filtration system. sigh. :confused:

[craigwatanabe]

I have two 5K tanks because it's total footprint is not as invasive as one big 10k tank, plus with two separate tanks if one gets damaged or leaks, I still have another tank intact.

I've been considering going to those low profile doughboys simply because of cost...it's way cheaper I'm told. One thing about fiberglass tanks is that you will have a greater tendancy for initial leaks that will have to be patched. At least you won't have to worry about rusting.

I prefer an enclosed tank as opposed to one that simply has a cover. My kid's elementary school teacher was taking a shower when her husband told her to stop. When she came out he took her out to their catchment tank and found fur floating on the surface and eventually fished out their dead and bloated pet cat that mysteriously disappeared a few days earlier. Yep I think I'll stay with an enclosed one piece tank setup.

As for filtering if you don't want to change filters every week then go with a sediment filter at the pump and a PUR faucet filter at the sinks and shower heads and you'll be changing the sediment filter about once a month. The sediment filters run about $4 each. The PUR filters will require less chang out because of the pre filtering.

If you go with just a charcoal filter that can filter to 1-micron then it'll be a weekly filter change but only at the pump as you won't need one at each faucet or shower head. These filters run about $6 per cartridge.

Some people go with total filteration with reverse osmosis and UV radiation. That's the most expensive and complete filtering you can get but not too practical as even county water isn't that filtered.

The best filtering set up is a Diatom filter where water is polished to absolute clarity and is chemically pure. These filters are so good that when used in fish aquariums it is recommended to turn it on for just one hour per month as it filters all biological elements that are conducive for a healthy aquarium.

One thing about excessive filtering is that you don't want to filter out necessary minerals essential for good health. Reverse Osmosis and Diatom filters will do just that.

I had a Reverse Osmosis filter but deemed it too expensive for practical usage. Now I simply use a sediment/charcoal/Pur filter in that sequence and change out all filters once a month with the exception of the PUR filters that seem to last about 5-months with all that pre-filtering.

My water is chemically purer than county water as well as softer and more alkaline (better for the body).

[SouthKona]

thanks craig, you've given me hope that i can not only keep animal carcasses to a minimum, but actually have "safe" water! i guess it's time for me to start doing some shopping-by-phone, getting prices and availability. i hope the water-system salespeople are trustworthy. :) any recommendations on companies for tanks/filters, etc?

[alohabear]

thanks craig, you've given me hope that i can not only keep animal carcasses to a minimum, but actually have "safe" water! i guess it's time for me to start doing some shopping-by-phone, getting prices and availability. i hope the water-system salespeople are trustworthy. :) any recommendations on companies for tanks/filters, etc?


As a son of former coffee farmers, this thread makes me chuckle a bit because all they used as a filter was a Durham bag and no one got sick :D

[SouthKona]

As a son of former coffee farmers, this thread makes me chuckle a bit because all they used as a filter was a Durham bag and no one got sick :D

that was probably in the days before leptospirosis, giardiasis, and salmonellosis. heck, nowadays i need to give a lecture to the kids before they swim in the freshwater streams because of all the diseases. but, that's subject for another thread... :eek:

[kimo55]

that was probably in the days before leptospirosis, giardiasis, and salmonellosis. heck, nowadays i need to give a lecture to the kids before they swim in the freshwater streams because of all the diseases. but, that's subject for another thread... :eek:



well, it's also back in the day when we all had healthier defense mechanisms. there's anodda woid for it; forgot the phrase.... Immunity something...
also, now, we use crap like that antibacterial soap and now, as a result, bacteria is growing hardier, and this kinda stuff doesn't affect it.

[craigwatanabe]

yeah and back then:

Certain neuro muscular diseases was thought to be a bad headache
Certain gastro intestinal diseases was thought to be bad fish
Certain birth defects was thought to be a punishment from God
Certain death was thought to be just poor health
Certain Memory loss was thought to be just old age
Certain sensory loss was thought to be flu-like symptoms

But the water was fine! :rolleyes:

Yep in those days of really bad pesticides and poor emission control I'm sure the water supply was pristine... :rolleyes: :rolleyes:

[kimo55]

yeah and back then:

Certain neuro muscular diseases was thought to be a bad headache
Certain gastro intestinal diseases was thought to be bad fish
Certain birth defects was thought to be a punishment from God
Certain death was thought to be just poor health
Certain Memory loss was thought to be just old age
Certain sensory loss was thought to be flu-like symptoms




ya mean, they are NOT!?

[DaveNSoKona]

Chemtainer 966-5454 16-118 Liilii St. (Hilo) sells those plastic jobies that Craig is talking about.

Pacific Watertank Supply (Kona) sells the metal kind like mine 322-2222

[DaveNSoKona]

it's not that big trees attract more rain, its more that rain makes for big trees. Trees are not good for catchment systems as the leaves fall onto the roofs and the decomposing leaves end up tainting your water like tea leaves.

Craig, if you study rainfall statistics from the sixties compared to today you will see a BIG change in rainfall. Big trees do effect rainfall in areas like west Hawaii where much of the rain is caused by thermal differences of the ocean and mountain.
"Forest loss can also make rainfall more erratic, thus lengthening dry periods."
forestsmonitor.org (http://www.forestsmonitor.org/reports/highstakes/part3b.htm)

I agree you don't want trees around your tank or gutters though. Aside from clogging up your catchment system it is a fire hazard. I was talking about deforestation effecting rainfall in surrounding acreage, not a few big trees around your house.