water tank connections and foundation ?

[bcarwell]

I'm connecting 8 round 2500 gallon tanks for a rain catchment system (each about 8 ft. diameter, 8 ft. tall). They will be in two parallel rows of 4 each, e.g.

X X X X
X X X X

And they will all be level on a flat plateu downhill from the house such that their tops will be at about the same height as the yard where it meets the foundation at the roof downspouts at the house. I have a few questions:

1) How would you interconnect the tanks to end up with one supply line to the pumphouse ?

EXAMPLES: X - X - X - X ------->pump house
T T T T
X X X X

X - X - X - X--------->
I
X - X - X - X

2) Where would you put T's and valves and why- for draining, cleaning, filling one tank completely before filing the next (?), etc.

3) Would you connect them all at the bottom or all at the top, or from a bottom going up to the top of the next one. I can see a benefit to connecting all at the top so silt isn't transferred to the next tank (e.g. only when a tank fills completely does it spill over to the next, with the "spill" being top water presumably with less particulate matter, but hey, what do I know ?)

4) What kind of base support material would you use ? Course sand, P gravel ? I was thinking 4 inches of course sand. I've loosened the dirt with some rippers on my box blade and removed the rock- the dirt left over is fairly powdery and has only a little amount of small rocks left, e.g. its almost the texture of sand itself (Central Texas). I could just sift and backfill the existing dirt and maybe no sand/pebbles needed at all ?

Any other suggestions/considerations on the tank farm itself would be welcome. Then its on to the pumphouse, pump/treatment, gutters, downspouts, roof wash, ... YIKES...

Thanks, Bob

 

[bcarwell]

Sorry, don't know why my EXAMPLES graphics didn't make it. The tanks are in two parallel lines with four tanks in series in each line.
One way I was just going connect the first 4 tanks in series, and then T in each one of the remaining four in between a different respective pair of the first series of 4.
The other way was to just connect the first 4 tanks in series like above, and then connect the remaining 4 also in series and just join the two lines of 4 tanks together at the end at the output of the last two.

Bob

 

[ultrarunner]

Neighbor has a set-up like this...

He built a pressure treated frame and added coarse sand then put the tank on top.

Piping is most Schedule 80 white PVC with some clear tubing to connect and allow for give and visibility.

Valve are plastic ball valves...

It's been 4 years without problems.

The supplier told him keeping the tanks out of sunlight will greatly improve service life.

 

[tommu56]

HERE YOU GO

 

[ustmd]

Curious to see what advice you get. We, like everyone else in Central Texas, are looking at putting in a collection system.

What type of pump are you using?

 

[Tractor Seabee]

Not enough info to really think it through. Open top tanks? What size pipe? What is the end use? How long between rainfall and complete use of the storage? Stagnation could be an issue with that much storage. If it is domestic water use that opens a whole new can of worms.

 

[Tractor Seabee]

Here is a thought on the foundation. Sand and pea gravel will squish out from under the tanks unless you constrain it laterally like with a curb. I would use 1 1/4" or 3/4" minus crushed gravel and tamp it down and level it. It will drain better also. Sand once packed down doesn't drain as well. Pea gravel is the easiest to level off inside a frame and is self compacting.

 

[Egon]

3) Would you connect them all at the bottom or all at the top, or from a bottom going up to the top of the next one. I can see a benefit to connecting all at the top so silt isn't transferred to the next tank (e.g. only when a tank fills completely does it spill over to the next, with the "spill" being top water presumably with less particulate matter, but hey, what do I know ?)/QUOTE]

You could consider water dispersion spyders within the tank for both the inlet and the outlet lines. slows water down withless agitation so solids will fall out.

Really need more information as to type's of tanks, estimated flow rates, water sources, contaminates etc. and a hint at the budget as that will be a deciding factor.

 

[beeforty]

I have had thoughts of something like this but it's down the list of priorities. here are a few. Top fill with T's to all tanks will make it easy to distribute in downpours, and don't forget to provide for overflow when the tanks are full. depending on how many downspouts you connect, the supply to tanks may need to be fair size, maybe 4" at least. With 8 separate tanks you will need lines at the bottom to draw the water out to supply your pump. Keep them up off the bottom 4" or so for sediment to accumulate so it doesn't go to your pump. Maybe a sediment filter in line for you supply from downspouts that is easy to get to and clean. On the outlet I'd use maybe 2" from each tank and bring them to a 3 or 4" section of line before your pump and put a firehose adapter that fits your local fire trucks. Your 20,000 gallons of water if full will go a long way to protect your home if they are full. Even 1/2 full that is 2 of our normal tanker trucks in my neighborhood:thumbsup:

 

[davedj1]

Not to discourage you all but, what are you collecting? If it only rains once a year you will be years filling those barrels! Just funnin'.
ok, seriously, how do you plan to fill them?