Tree growing into water tank

Ugh - I seems like we are suffering from a water course right now...

Fist the spring that had been supplying us all winter while building our house dried up to a tiny drizzle, and no we had not yet installed to pump in our well. Then we hadn't finished the first flush system when we had a giant rainfall (we thought there would be none untill September/October). Then we finished the first flush system, and had a little more rain before the silicone had dried... So the silicone broke again ...Argh!

We ordered a pump, it was in back order, two weeks waiting - we got a pump, installed a pump (70m up the mountain, 70 m down the well), it did not work. Pulled the pump back up - one of the "shoes" in the cable had fallen off while we lowered the pump and caused the malfunction - bravo! We fixed it, lowered the pump back down - now the generator won't work...

Decide to buy a small solar panel (so my hubby can work) send the generator of to service and buy water to get by until the generator gets back from the work shop.

We got 8000L of water yesterday, today 1000L is GONE! We had the drip irrigation running very very low on less than 10 trees all night and washed to loads of laundry on our A+++ washing machine - I watered the animals and a few plants - that's it! We might have used 200L, but I doubt it.

So I go up to our water tank - that was fixed 6 months ago (had not been in use in 30 years) - and right below the water surface there is a tiny crack, and from that crack I can see tree roots sticking out in 5-6 different places. Ugh

There is a giant carob tree planted in front of the water tank - I suspect it is the culprit. Our friend suggest we fell the tree and repair the water tank... I'm thinking (aside from thing the idea of felling a tree) - isn't that more work than building a new water tank? And is that even possible? I mean the roots might even go
under the tank... How would I kill that tree without digging out the water tank?

There are methods to patch holes like that, it was a problem all the time here. Hydraulic cement or numerous different caulks or linings.

My grandpa clear cut all the trees within 100m of the cistern and he still got roots in it. Can't be avoided, you just have to deal with it.

Cut the tree down and the roots will prune back (but probably not the ones getting the water!). It is really hard to kill a tree that has infinite water supply without chemicals. Girdling the tree may work. Copper nails may work. I just don't know much about carob trees.

Thanks

We can't clear cut everything within 100m because half the tank is not even on our land and since it doesn't work, I won't. I will.not.kill.a.tree w. Chemicals - ever! If I did I wouldn't have asked here.

So maybe - haydraulic cement, and it will take some years before it get's back in?

Edit: and paint it with water resistant caulks?

If you don't take out the tree, you will continue to have problems. It knows where the water is.

You could line the tank with flexible membrane (food safe pond liner). It is supposed to just move if a root tries to get in, but I don't know how true that is.

But if you take care of the roots, hydraulic cement will a concrete tank. (I didn't even ask what the tank was made of, just assumed-oops). If it isn't concrete, let us know how it is made.

Hmmm.. What is it made off? Good question - rocks, but what binds them together... I don't know. The house it rocks w. cob (or some clay/sand mixture without straw), but I don't know how old the water tank is...

I am a service plumber and I can attest that no, killing a given tree probably wont help and yes hydraulic cement works wonders for leaks!
I have only been doing this job for two years, so I could be wrong but I have customers who have taken out trees due to roots invading the sewer line, yet I find more roots from the tree next door.

I am pretty sure certain the leak comes first, and the tree follows the water back, inserts a tiny root and expands from there.

I would trench right through the roots you know about, patch the know hole, fill in cracks and such on the inside of the tank and see if that works.

I have a relatively young (compared to many European homes) 91 year old house, and do you know what I do about the plumbing in it?
As little as possible. It can be like tugging on a thread only to find your sweater unraveling, so be careful...

It might push up against the container quite aggressively in search of water, just by chance. This is how trees break bedrock and create soil. This force creates a crack in the tank and and then the tree can enter. It is not because it can sense the water, it is just stretching out to find some water. Condensation underground might allow the soil to get moist, which would be a source of water.

If you cut the tree back, and let it regrow, the roots will die back quite a bit. The tree will regrow from the remaining roots and you'll buy some time till it is pushing back.

Removing the tree can be done with girdling and weekly sprout removal, if you have the access and time.

The thing is ... that we were going to build an extra tank or two anyways as this one is too small to get us through the dry-season. And it is not like we have too many trees as is around here

What I am wondering is - maybe it would be better to just build the extra water-tank 8000L larger (that is what the current one holds), and use this one as a tool shed or something. Removing the tree sounds like a lot of work, maybe that work would be better invested in a new tank. But if we could just line this one with hydraulic cement and have it working for just a few years, when we are more settled here, maybe even have a spare tank (we had not planned on building the extra tank right now). But I am not sure which path to take.

Right now we have ordered 4x1000L cubos - as they will be more than sufficient while pumping water from the well - but they are not nearly sufficient for rain-water catchment.

We have been thinking hard these past 24 hours. Thank you all for your input.

What we have come up with is this: We will see how far down the water level in the tank drops - if it is not below that visible crack the tank can still hold 3000L and we can still use it temporarily, if it drops below we need to buy some cubes to hold water until we have a permanent solution.

We will not try to fix the tank - the work to kill a tree is simply not worth it. We were going to build/buy one or two additional tanks anyway, so that is what we will do, just build/buy them 8000L larger (since my husband is still working full time we are considering putting up an advertisment here on permies or facebook for someone to do it for us - all builders in Spain are super busy working as waiters all through the summer). We just have to figure out whether we want to buy a ready made tank or build a one in ferro-cement (input and experience is very welcome).

The tank will then be used as a tool-shed - it only need a little insulation under the metal roof and a door (and the tree offers great shade).

We still can't get the pump running - we bought a new generator (buying 2,3 kW solarpanels is not feasible right now) yesterday, and are shipping the old one off to service - but no water is comming out of the tube. We know there is water in the well, we have checked that the pump is running, but no water is comming out... Paul is right - living off grid is like running Linux.