Section One - Rain Catchment
This is an idea applicable to most inhabited areas that can be simply enacted with a bit of government will.
Huge amounts of energy are used every day to purify and pump water in cities around the globe. It is estimated that human water demand will increase by 36% in from 2000 to 2050 in Florida. Much of this water, once pumped and used, then ends up costing us more energy to clean before we put it back into the environment. This process is essential. Clean water is the life blood of human habitation. One simple way we could reduce the energy and environmental cost of this process in most human cities is to use nature's gift, rain. What I propose is that the building codes be changed so that all new construction, and all major renovations, where adding the necessary components would not increase the total cost by more than 10%, be built with a rain catchment system. This takes the rain that lands on the roof and directs it into a storage tank, this can be of any type of tank, situated just below the roof line. This tank can then gravity feed the toilets removing the single biggest user of water in most homes from the city's water supply system.
A quick sketch of how the system would work is as follows. Rain falls on the roof and is directed into the leaf shielded gutters. A pipe with a coarse screen cover to prevent large refuse falling down it directs this water into a storage tank. This tank is equipped with an overflow that will drain into the house's gray-water tank. More about that later. Here the water is stored until a toilet is flushed.
When a toilet is flushed water gravity flows from the storage tank past a valve though a coarse filter and past another valve. The valves are there to facilitate cleaning the filter screen which is easily accessible through a hatch in the pipe. Cleaning this filter would be no more complex than replacing the air filter in a central heating system. Close the valves, open the hatch, pull out the filter, rinse it off, put it back, close the hatch and open the valves.
After the second valve, the water reaches tank two through a float valve similar to the one you probably have in your toilet right now. This tank and valve assembly is very reminiscent of a household toilet's back tank. The only real difference is that it contains two float assemblies. One float valve is hooked up to tank one, allowing the rain water to fill tank two. The second float valve is situated so that it will never open unless tank two is less than a third full. This second float valve is connected to the city water supply in case tank one runs dry. This ensures there will always be water to flush the toilets. The water line serving tank two from the city main is protected by a one-way valve so there is no way the rain water could infiltrate the city system. From tank two, water lines run to the toilets in the house supplying water for flushing.
Advantages
The advantages of a system like this are many.
- Less water is pumped and purified saving energy.
- It reduces the strain on existing water treatment facilities extending their life and allowing the existing facilities to supply a greater number of homes, thus putting off the expense of building new facilities.
- In an emergency, people have a store of water that a quick boiling and trip through a coffee filter will render drinkable.
- It removes a huge amount of runoff water from the municipal waste water system when there is a rain storm, because the catchment tanks must fill before any of that water passes through the overflow. I am the first to admit that the real solution to this problem is to have the storm and waste sewers separate, but as that will take time to accomplish, very real benefits can be realised from this water diversion. Note, the waste water should still be treated due to local pollutants, e.g. road toxins from vehicles.
Objections
Now for the inevitable objections.
Objector. What about my dog, it drinks out of the toilet?
Answer. That's disgusting at best. The water in your toilet is riddled with bacteria or riddled with chemicals, take your pick. Give your dog a water bowl and put a child guard on the toilet lid if you have to.
Objector. What about the old people having to wash that filter.
Answer. If they are fit enough to wash the dishes they are fit enough to do this. Honestly, most older folk I've talked to about this liked the idea of being a little less dependent on the government to supply something as essential as water.
Objector. Why should we do this? Things have always been fine. It's all bunk.
Answer. Wake up. The world is not the same as it was a hundred years ago. We have a much larger population, we have far more technology, the amount of carbon we as a species are releasing into the atmosphere is substantially higher and there are hosts of chemicals that exist today that didn't twenty plus years ago. The world has changed, as has our place in it. Things are not as they have always been. After all, did you hitch up a buggy and drive the team five miles into town to do the shopping? How about walking to work? Things have changed. We now have to accept it and work to keep our standard of living while mitigating the impact of those changes.
Please note: Intelligent objections to this system, or anything I mention here, and suggestions for refining it are most welcome. I don't mind intelligent challenges just the ones based on an unwillingness to accept anything new or a complete disregard for the well being of future generations.
Problems with the System
These exist with everything and are why environmental technologies are best used in a targeted way. The main problem with a system like this is that it is of limited value in multi-storey apartment complexes. Unless one is in an extremely rainy environment, it is unlikely that the limited roof space of an apartment building would collect enough water to make much difference to the overall water consumption. This may not be true of some low rise buildings, but for many structures the cost may out-weight the benefit. In this application the local rainfall and size of building would have to be factored in on a case by case basis to determine system viability.
The Next Step
The above method is the most basic of systems, but it can be expanded drastically. The simplest expansion would be to add a fine-grain filter into the system and use the rain water for the washing of clothes. A further expansion would be to add a system for sterilising the water and use it for drinking and bathing.
Sterilising the water can be accomplished by running it through a UV light tank, or by chemical means. Boiling would also work although it is energy intensive.
Information on these systems can be found in issue # 199 of Mother Earth News and a variety of other sources, some of which are listed in the article.
The reason I shy away from this more advanced system is complexity, cost, and the knowledge base needed to maintain it. The advanced system would seem to lend itself to rural areas, especially ones where human activities have poisoned the ground water making well-water unavailable.
Section Two - Gray Water
