New water tank

About a year ago I mentioned that we needed to replace the water tank the spring water flows into before being pumped up to the house. A while after that we ordered the new tank. The plumber and the earth excavation man have finally managed to coordinate and appear to install the new tank!
We cut down a tree yesterday and strimmed to give them access. They disappeared down there all morning with their mini digger and made lots of crashing and bashing. They reappeared briefly to say 'eerm do you want to keep the old tank??' and looked very relieved when we said no. I guess they broke it up to get it out.

When we ventured down at lunch time to take a look they had dug down to the rock underneath to sit the new tank on that and created a giant trench to allow the area to drain. They say we need to maintain the trench otherwise it will fill with mud and the tank will float away. Nice! We are thinking about what plants we can plant down there to stabilise it. Would need to be shade and wet loving.
The tank is much bigger than it looks in this photo. 750l. Another improvement on the old tank is a filter on the water inlet, the old tank used to get all silted up inside from time to time - resulting in lovely brown drinking water and a fun day trying to clean it out.

It all looked good. Until we started fiddling with it! The plumber told us we needed to clear the pipe above the tank as we did last summer (it is a lot wetter and muddyer now given all the recent storms) and put back the slate roof of the water channel - they had removed it during their work. He told us we needed to remove the pipe from the tank so the mud we would stir up wouldn't go in to the tank. All good - until we managed to get some stones and twigs wedged in one of the pipes. We did  eventually get them out with the help of some wire, but in the mean time water was going everywhere and we were worried it was going to undermine the foundations of the new tank. We then had a very trying time getting the pipe we had removed back on. We didn't really understand the mechanism of the bolts (still don't) and the water flooding everywhere didn't help. We were sure we would lose one of the little bits... but luckily didn't!

Funny story - Last time the plumber was here - last autumn - he managed to catch a branch of the plum tree at the top of the drive on his van. He drove off at high speed and didn't seem to notice, dragging it half way down the drive before it fell off.
This time just after he arrived another branch went creeeaaaak crash and fell off just behind his van. We think the tree has been waiting to get its revenge, but just mistimed it!

It is a shame as it was laden with soon to ripen plums. C'est la vie as they say!