The Water Catcher

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Trails live and die by water, and one of the most important jobs at any set of trails is how you manage it. Whether that be planning out drainage, tarping the jumps, or in this case gathering and storing water. I’ve seen more than a few sets of trails fall into disrepair and eventually be abandoned due to a lack of water. Finding a spot close to some kind of water source was one of the main goals when we started our spot three years ago. We eventually found a spot close to a river and got to building. It quickly became apparent that though the river was relatively close it wasn’t exactly ideal to get water from. The first problem was that we could only get water during high tide. It was more of an inconvenience than a problem, and was remedied with an Iphone app that sent tide alerts. The main problem was that making those runs down to the river exposed us to the eyes of people in the neighborhood. We do our best to keep the trails hidden, and dudes walking into the woods carrying buckets of water definitely wasn’t helping that. Luckily we discovered a water source right in the middle of the trails and haven’t had to go out to the river since. Before we discovered that water source we were doing everything we could to try and collect any rain water we could. If we knew it was going to rain we would leave the buckets out in the open with the hope of catching a little extra water. It worked but it never really added up to too much.

Can You Dig It Buckets

We even started trying to save the water that had collected on the tarps. After a while of doing that we started to realize that the tarps were actually collecting a good bit of water, though it was a pain in the ass trying to get it from the tarp and into one of the trash cans we were using to store water at the time. It wasn’t until after a trip to Posh and seeing the water tote and little tarp they had hanging above it to collect water that I really started to put a plan together to try to capture more rain. As I said, up until that time we were storing water in four trashcans that we had drug back there. It worked fine but we could only store around 150 gallons. After seeing Posh’s water tote I knew I had to have one. A little poking around Craigslist and I found a guy selling them for $50 a piece, and lucky for us he was willing to deliver. We went ahead and decided to buy two, and a few days later the guy dropped them off right by the trails. We drug them through the woods and set them up side by side in a clear area where we figured they would catch the most rain. Here’s where a bit of experimenting started to happen. We originally thought about sitting baby pools on top of them to collect the rain. That got put on the back burner the because we found a lid from one of those giant yellow water barrels they set up at the end of jersey barriers to keep people from ripping their cars in half if they crash into them. It sat perfectly on top of one of the water totes, and I drilled holes in the middle of it so it would drain right in. It worked, but it never really collected the amount of water we were hoping for. It just didn’t have enough surface area to be able to collect that much water.

One night I was home on the computer and was curious to see if there was a formula that would tell you the amount of water you could collect from a given amount of rain collected from a specific size surface. It didn’t take long to find exactly what I was looking for.

Rainwater Catchment Formula

What you see above is the formula for predicting just how much water you can collect from say something like a tarp hung up to collect it. Basically it’s the square footage of your catchment area (i.e. tarp) X inches of rainfall X a conversion factor of .623. The conversion factor just accounts for an approximate 40% loss from things like evaporation and wind blowing the rain. No need to break out your calculators though because HERE is a site where you can just input your information.

So with the motivation of how much rain water we could potentially catch we went to work constructing something to do so. We used what we had laying around the trails to build our rain catcher. The thing about trail builders is that we are a resourceful and ingenuitive group, so just use this as a rough guide for building something of your own with the materials and storage containers that you have.

For our rain catcher we went with a standard 6’x8′ tarp with eyelets. Sure we could have gone with a bigger tarp but since things were still in the experimental phase we figured a smaller more manageable tarp would be better to start out with. Since the idea was to have the water that the tarp caught collect in our water tote that’s where we started. I rigged up an anchor point on the lid we had sitting on the tote with some tarp pins and an old carabiner. This needed to be the lowest point of the tarp so the water would drain in.


From there we worked our way to the sides. We had to improvise since there weren’t any trees or anything to attach the front sides of the tarp to. Two shitty shovels we had laying around did just the trick. We stuck the heads of them into the metal frame of the water tote, and with a few zip ties to keep them in place we were in business. Then it was just a matter of securing the tarp to the shovels. Once again we broke out the zip ties and used them to connect the ends of the tarp to the shovels. I slid the zip ties up until they gave the end of the tarp a bit of a V shape and then used duct tape to keep the zip ties from sliding down.


We had a few small trees located behind the back of the tarp so that is what we used to anchor it to. I wanted to make sure that the tarp maintained a flatter shape towards the back so I zip tied some small branches to it to give it some support.


You all know how gravity works so obviously you’ll want to make sure that the back of the tarp sits higher than your anchor point at the front. I used a few bungee cords to connect the rear of the tarp to the surrounding trees. You’ll want to play around with the tension and anchor points a bit to get the tarp to sit correctly. You could also use rope instead of bungee cords, but the bungees allow the tarp to have a bit more give in circumstances like high wind. After you get everything all rigged up take a step back to see how it’s looking. If everything is looks good then give it a test by pouring some water on it. If it funnels in to your collection point your all set.


Like I said, we went with a 6’x8′ tarp. It fit the space we had perfectly and though we originally intended on rigging up something bigger, we never got around to it. There have been days where I’ve come back after a good rain and had over 40 new gallons of water in the tank. Not bad for a tarp, some duct tape, and a few zip ties and bungees!

Water Catcher

This is how we made ours, but with some experimenting it could be done a number of different ways. You may not have a water tote but you could rig up something like this to collect water into whatever container you do have. You should also consider adding some bleach into your container to keep the water from getting funky. It will also keep mosquitos from laying their eggs in there. Those things love still stagnant water, and the last thing you want to do is give them another place to breed!