Urban Survivalists

First of all, we would like to welcome you all to our  contest.  We will be offering a free t-shirt and a feature in a blog post to the person who can best describe their definition of sustainability to us, but the deadline is February 20th! So hurry up! Please check out the link for details.  In the mean time, we are going to continue our build of the rain water collection system.

Stand for first-flush system:

Since the first flush pipe was not tall enough on its own to reach the gutter downspout, we decided to build a wood and cinder block stand for it. The stand raised the elevation of the first-flush outlet so that it would be higher than the inlet to the roof washer. We also had to make a wood stand-off to brace the first flush system against the house so that it lined up correctly with the downspout.. The stand-off and wood stand were made of standard 2×6 and 2×4 pieces of wood that we had sitting around. This was a good opportunity for using up scrap lumber. The stand-off was screwed into the house siding and the cinder block and wood stand was just placed on the ground. Hokey, we know, but very effective. Since this is a trial system that will definitely be changed in the near future, we decided that anything more elaborate would be unwarranted.

Connecting first-flush system to the gutter downspout:

We decided to go and get a 4″ to 2″ pipe tee, as seen below, to be placed at the top of the first flush system. This will be the inlet from the gutter to the first-flush system. The tee works because once the water reaches a certain point, it is then rerouted to the sand filter. Then the first-flush system was placed on the wood stand and plumbing tape was used to connect the first-flush to the stand off.

Proper use of plumbing tape is essential for our sorts of builds. Here’s basically how it works:

• Screw in one side where you want it.
• Wrap the tape around the object you are securing and put a screw through one of the holes near where you want it to be secured but just a bit back from it’s final location.
• Screw in this second screw angled toward where you want to be so that as the screw draws itself into the wood it is pulling the tape tight.

With only a little bit of effort you can make a very secure strap connection. This has the added benefit of being easily removable if you want to change something which we ended up needing to do almost immediately.

Connecting first-flush system to the roof washer:

Now that the first-flush system is secured to the siding of the house, we added the pipes that connect the first-flush to the sand filter. We decided not to use the pipe cement for these so that the first-flush system could be removed easily. This allows for easy upgrade of either the first flush, roof washer, or even the pipe connections themselves.

Now that the pipes are in place and we know where the inlet hole to the roof washer needs to be, we can close the top with a bucket lid and cut a hole in it to fit the inlet pipe. This keeps vermin out as well as neighborhood cats who like sand for other reasons…gross.

Testing the system:

Once the connecting pipes were in place, we were eager to see the system working. During this entire process it had been raining so we were certain to see the system in action…except it didn’t work out that way. Immediately upon completing the whole setup, it stopped raining. DRAT!

Undeterred, we filled up the first-flush system with water from the garden hose. As seen below, the water is coming out nicely from the outlet at the bottom of the first-flush system. In addition, the pipe tee worked as we had planned and rerouted the water to the sand filter once the first-flush was full. There was just one problem, the outlet on the first-flush seemed to be too large. It was draining water faster than the rain from a small storm would fill it.

This was no good since the first-flush’s slow draining ability are what make the whole system functional. We would need to fix this if the system was to operate properly.

Fixing the first-flush:

This lead us to ways of making the hole smaller on the outlet to the first-flush system. We used a transfer punch to deform the plastic around the hole and decrease the outlet size. This seemed to work as we ran another test and the outlet stream was greatly reduced.

First real life rain event:

The night after completing the system and the small fix it needed, it rained. Inspection of the barrel the next morning showed that we had collected 1/3 of a barrel’s worth of water. Not bad! Since we are only collecting water from less than a 1/4 of our roof area, we can expect to fill well over a barrel in a given small-sized rain event. The roof washer had picked up some sediment from the outlet to the first-flush system as it was supposed too and the water in the barrel appeared to be clear.

One problem that was found was that the small outlet hole on the first-flush system had already clogged with sediment. We were hoping that the screening we placed inside would help prevent this but apparently smaller particulates build up in the outlet hole rather fast. A quick fix for this is to put a beading needle up the hole to clear out the particulates but this is really like applying a band-aid to a sucking chest wound.

We’ve read in a number of places that the first-flush system is one of the most troublesome components in a rainwater harvesting system. New and expensive models utilizing a semi-permeable ball-float which becomes clogged with sediment, as ours does, and both systems also are susceptible to freezing weather. As yet, we have seen no flawless first flush system available. We intend to continue working on solutions to this critical sub-system and making those plans available here.

If you have any ideas or have read any great fixes, please contact us and let us know.

Total cost and bill of materials used:

In our system, we used the following materials:

This comes to a grand total of $81.03. Not too shabby, but we think we can do better with other installations. For instance, a substantial part of that outlay was to install new gutters because the old ones were unusable. Indeed, they were just plain non-functional all around. If you happen to have functional gutters, then you will not need this added expense.

For any subsequent systems we build, we will not need quarts sand, pea gravel, trench wrap, or mosquito netting just to name a few things we paid for this time. Your expenses may vary but this should give you a ball-park figure for how much it can cost.

Next week and beyond:

For now, we can conclude that the base system for rain water collection is complete. We will leave this installation in place for a number of weeks and monitor it’s performance. When an idea hits us for improvements, we’ll do it and report the results. The system should keep evolving in this way over the next several months until it becomes a fully functional system with only minor annoyances.

Next up is our water filtration unit. We already have a lot of the parts for this and are working hard on the system design. Over the next few weeks we are going to flesh out a final design for you here. Since this system is much less installation dependent than our rainwater harvesting system, you can expect to get drawings and schematics as well as a firm bill of materials. We are looking for a total cost to build a water filtration system of somewhere around $400 though don’t quote us on that yet!

Thats all for now, take care.

P&S