Polytunnel watering.

Hi Everyone,
Am new to this site. Saw some posts about polytunnels and watering, which is why I registered. Can I find them now? No, I've searched everywhere.

I put up a 40ft tunnel last year. I think I watered too much. This year I have a drip hose, but worry that is not watering enough. Does this actually reach the surrounding areas?  Not sure if I should water every day and for how long. also the person whose meassage I saw was talking about guttering on a PT. How does one do that? They also mentioned ideas for making one themselves. I'd be very interested to know how to do that! I'm about to aquire an IBC container but have no sheds etc near the polytunnel
Would be grateful to recieve any advice on this subject.
Hope this reaches the right place. I do find these sites totally confusing!!!

I have a 40ft x 12ft polytunnel.  I have a standard plot on a site that is privately owned - we have no mains water, but are able to draught off a small river close by, although this is never really enough unless you are down there very often.

I get sent away on business for a couple of weeks at a time, and although I do have someone who goes to water for me, it makes my life much easier to reduce the manual effort as much as possible.

After a couple of years of experimenting, this is my setup:

 I have 'gutters' on the side of the tunnel - you can buy these now I believe, but I make mine from tumbledrier hose (using wire cutters, split the hose so that you have two even halves), and I tape it to the side of the tunnel with polytunnel repair tape, making sure I have enough slope for the water to run down into the collection tubs.

Since I have a 40ft tunnel, I need 5 'gutters' to cover the whole length on one side.

I use the big 'trugs' (about 45litre?) to act as collector tubs for the runoff.  When they fill up, I manually have to empty them into a large (110litre) tub (ten quid from B&Q) that I use as a 'holding tank', at the bottom of my IBC tanks.   (Still haven't worked out a decent method of automating this, as it would have to go 'uphill', and need to be pumped)

I have two IBC tanks stacked at one side of the front of my tunnel (the higher side of the ground).

I have a small bilge pump in the holding tank, attached to a hose that goes to the top of the top tank.  A connector hose joins the top of the top tank to the lower tank, so that once the top tank is full, it will overflow into the bottom tank.

When I have water in the holding tank, I attach a car battery to the bilge pump and switch it on.  It takes about 5 minutes to pump the 100litres or so 8 ft up into the top tank.

For watering, I have a hose attached to the top tank that runs through the frame of the tunnel to the inside.  Inside it connects to a battery-operated timer, then through a filter (stored water can get very mucky), then to a 5mm feed hose, and on to a 5mm soaker hose.  (I used to use a standard hose, but the pressure wasn't enough to make it work properly).

The timer comes on for 90 mins twice a day, and uses about 80litres of water a day.  This is during the very hot, dry weather we've had lately.

Although the top surface looks dry, the soil below is well moistened throughout.  I use 3-4 lengths of hose for each 3ft wide 'bed' running the length of the tunnel. (I have a bed on each side, and one in the middle, with two paths running the full length of the tunnel)

This system is working well for me now - I have so far only collected water from one side of my tunnel, as I have the end plot on the site and it has been hard to get to the other side.  I have a total of four IBC tanks on my plot (the other two collect rainwater on my shed) and was able to fill all four tanks over the winter with more to spare!

I am about to put in two more IBC tanks, as during this very long dry spell I used all 4000 litres and finally had to refill using the standpipes from the river.  I'm hoping that I'll be totally self-sufficient with 6000litres!  I'll also install gutters on the other side of the tunnel as access has been improved this year.

Happy to answer questions, if you have any... 

Good luck - tunnels are ace!