Note: this has been published to DK. If anyone's interested, the version there contains some links which may be useful, plus some text formatting that may make it easier to read. I just don't have the energy to add all the links and formatting back in right now.

Now that the Flint water system has been transformed into a toxin delivery system, the main conflict has revolved around what to do about the pipes distributing water to the populace. Democrats call for a complete replacement of the entire system (at a cost of about $1 billion, or maybe $1.5 billion), while the Republicans do everything they can to delay into eternity any action at all. Meanwhile, the city struggles to provide water and get at least a little rebuilding started.

The water system in Flint has been ruined. What to do? At this point, Flint is limping along on emergency methods such as bottled water and filters – with much of it through ad-hoc charity operations, as the rebuilding proceeds in fits and starts. Flint has a long a difficult time ahead. Yet now is exactly the time to examine the future.

The battle rages over whether to rebuild the infrastructure, through malign neglect to reign over its collapse (Success!), to turn it into a fief for the rich and powerful, or some combination thereof. There is another way. Rather than rebuild the conventional water system – replace it with a different kind of system. Rather than recreate a vast root and branch system, “let a thousand flowers bloom”. Instead of people receiving their water from the ground (or, in Flint’s case, a polluted river), build a system so that people receive their water from the sky. Install rainwater catchment systems on every house.

Think about a city which implements a comprehensive system of rainwater catchment, at the individual house level, at a block level, at a community level. Clean water, without the need for extensive treatment. (And why is river water so polluted? That’s a hefty tome in itself). No draining of rivers, with the environmental degradation that comes with it. No draining of aquifers. For many, no dependency on the local government.

Flint, declare your independence.

Right now, there are rainwater catchment projects in place around the world. Here, in the U.S.? It's not only rare, it's typically discouraged in the law. Until very recently, it was illegal to capture rainwater in Colorado. But there are groups and individuals who are working to change the situation. Will it be easy? No. Change rarely is. But it is feasible.

Contrary to what I’ve heard for years, catchment systems tied in to roof gutters work, and not just on metal roofs. In examining a study (pdf, 1.2 MB) performed in Texas in 2010, I concluded that the everpresent asphalt shingle roof can be a very good source of clean rainwater, with the biggest concern being turbidity. If I were in Flint, I'd be ecstatic to have water minus the lead.

Flint has enough rainwater — if habits change.

Total water available obviously depends on the annual rain in your area, and, if you use the easiest method of harvesting rain from your roof, the size of that roof. In Flint, the average annual rainfall is about 31 inches. If 10% is discarded by the catchment system as the initial dirty runoff, that gives you about 1.5 gallons of water per month off each square foot of roof (31 inches x .9 / 12 months / 12 inches x 7.5 gallons per cubic ft).. Which brings up an important point; that's not enough. Not for the way we use water now. If a household uses 5,000 gallons per month, they need 3,333 square feet of roof. Or they need to change their habits. A list of ways to reduce water usage is easily found, but I suspect the residents of Flint are now well versed in finding ways to reduce their water usage.

For those in multi-family buildings, the roof option isn’t available. That is where the municipality comes in. Not to construct a centrally controlled system, but to construct rainwater catchment systems. Not enough roof space? Then build more “roofs”. Not walls, not foundations, just structures which channel the water into cisterns.

It would cost less than replacement of the old system. It’s true that rainwater harvesting can be expensive; whollyH2O says $3,000 to $10,000 per home, while texascooppower says $8,000 to $10,000, with the largest cost being for a cistern. But the maximum estimate per home is right in line with the rebuilding estimate per person; $10,000. And it’s hard to believe that the price wouldn’t be less, especially if a municipality established its own factory for the production of cisterns.

There are sticking points that come immediately to mind:

Winter. Snow. Ice. Protection of cisterns from freezing. How to do the equivalent of a first flush with snow.
Financing. I expect that financing a plethora of projects on private property is vastly more complicated than one massive project.
Multi-family residences. Guttering has to be replaced with a different system for collecting rainwater.

And of course, getting into details, any lead roof jacks would need to be replaced. That would be the worst kind of irony to leave them in place.

But do those issues, or any number of other issues, override the benefits? There are people in Canada who don’t think so. As there are in India. Israel. Sri Lanka. South Africa. The UK. Texas. Yes, Texas. They even have a publication; Harvesting, Storing, and Treating Rainwater for Domestic Indoor Use (pdf, 1.5 MB)

How about Flint?