2 tonnes an hour

The biggest asset Chez Blob is our 17m x 9m polytunnel. It has a lot more utility that our most expensive asset - the 9m x 4m array of solar panels which we had installed in April just S & downhill of the tunnel. The tunnel is where we dry the laundered wearables; where we grow spinach & beans & tomatoes & squash & tarragon; where I can touch up a chain-saw and store kindling. The only draw-back is that it never rains in the tunnel and even that is only a problem w.r.t. to the veggies.

But it for sure rains on the plastic of the tunnel and from the beginning there have been gutters along each of the long sides which capture rain-water and deliver it to containers varying in size from 20 lt to 1,000 lt. If you add them all up we have the capacity to store nearly 3 tonnes of water [obsessive details and itemisation] which may then be eked out each evening to where the thirsty plants require it. I've said before that, in an ideal world, our average annual rainfall [~1,000mm] was delivered in increments of 10mm every third night through the year. In rose-tinted memory, it was like that in Olde Ireland but now we can expect to go for weeks without any rain at all and did so in 2018, 2023 and now again in 2025.

It was terrible dry for long stretches of the Spring this year and in July, I was reduced to using well-water to irrigate the veggies. I hate doing this because, since we changed the submersible pump in April 2024, prolonged running of taps drags silt up from the bottom of the well, and I have to clean the filter. On the w/e of 19/20 July we were served a dump of rain which topped everything up again. Then nothing for 5½ weeks and I was slopping an algal soup out every evening as the barrels steadily ran dry.

We were promised the scut end of Hurricane Erin on Tuesday 26 August - without the wind but with the hope of some rain. I cleaned the gutters, checked the hoses, mustered the buckets in anticipation. Wednesday, I was woken in the dawning twilight by the drum of rain on the roof and went up to make sure The System was working. It was wonderful and not before time. For two pins I would have [frighten the horses alert!] stripped off and danced in the deluge.

It looks like we caught about 2 cu.m. = tonnes of rainwater between dawn and breakfast. Which is consonant with the fact that we had about 18mm of rain that morning and the gutters run full length and capture close to all the rain that hits the plastic - 17m x 9m x 0.018m =  ~2.75 cu.m. As mentioned we had another wet front slob through on the morning of 03Sep25, so we are now brimful at a time when we don't need it . . . but the soil microbiota in the polytunnel is having a fiesta.