Tuesday, March 24, 2009

The Vital Question of Water


One Saturday each month, under the dancing shade of a grove of mesquite trees, Doña Felisa presides over a meeting of La Biznaga's water committee. Felisa is thin, neatly dressed and coiffed, and all-business. She takes meticulous notes of the proceedings which invariably revolve around money or how often and when to turn on the well pump so the neighbors--that includes us--can fill their underground cisterns or the tinacos, the black plastic rooftop water tanks that are ubiquitous throughout Mexico.

The dozen or so attendees, almost all women, sit on the ground and are not afraid to express objections or just grumble. When all the business is transacted--or Felisa's had her fill of bitching and gossiping--she ceremoniously announces "this meeting of the water committee is adjourned" as she slams her notebook shut.

The only regular male attendee is likely to be Lucio, who looks to be in his early forties and is the pocero or "well man," the linchpin of La Biznaga's dicey water distribution network. He's in charge of switching on the water pump and opening and closing the valves so everyone gets their twice-weekly allotment of water.

It'd be a reliable enough setup were it not for Lucio's battle with booze. Some weeks he'll neglect to turn the water on or off, causing some tinacos to either overflow or run dry.

It all depends on how Lucio is feeling that week and there's no customer service phone. If you need water, your only recourse is to go on foot and try to track down either Felisa, Lucio or Lucio's sober and far more dependable brother, Felimón.

¿Qué pasó con el agua?

Undaunted by his erratic service, Lucio occasionally puts the touch on the neighbors for "tips" of usually 10 or 15 pesos or approximately one dollar. Some of the gringos oblige, figuring that as unreliable as he may be it's preferable to keep Lucio on your side rather than piss him off. After all, he's got the keys to the pump.

The finances of the water system are not altogether clear. The going rate for a toma, or hookup to the system, is approximately US$1,000, a sizable amount in these parts. But then the monthly fee, for whatever water Lucio manages to provide, is only about US$3.50. About six months ago the water committee raised the monthly fee by three pesos or so, about 20 cents, but then rescinded the increase after some residents complained.

The money collected goes towards pump repairs and the electricity to run it. It's not clear who pays for repairs of the motley distribution system, a mess of galvanized and plastic pipes, and plastic hoses of various widths that run above and below ground in no particular pattern. We've already spent approximately US$100 patching various leaks near our ranch.

Much to her credit, Felisa is a water conservation hawk. She'll trudge along the waterlines regularly and suspend service if she spots any leaks. She's even visited our construction site to be sure water was not being wasted. I don't know how much Felisa gets paid, if anything, but hers is quite a responsible job and she does it well.

So far the water pressure that reaches our place, coming off a 2" line, is impressive. We can refill a 5,000-liter tinaco in a few hours. That should be enough to keep our household supplied, even allowing for disruptions caused by Lucio's drinking bouts.

So far. We have serious doubts the existing system can supply the growing number of homes that will be built around us as Don Lucas continues to split up his sizable ranch and sell off one-hectare parcels. Home construction may stall for the next few years because of the global economic crisis, but it's inevitable that La Biznaga's hard-working well will begin to gasp sometime during the next ten years, as more people move into the neighborhood.

We have thought of applying for a permit to sink our own well but that takes years of bureaucratic finagling and as much as $40,000 in permit and drilling expenses. It's not clear either that the state will grant a permit for a private well as long as we have an alternative source of water, no matter how feeble or unreliable.

That is why we opted to build in a rainwater collection cistern into the new house, a cistern so large and massive that right now it looks more like a swimming pool. That has set us back at least two weeks in the construction of the rest of the house, in addition to approximately US$10,000 in costs.

If the future water supply were not so uncertain--if we had access to the municipal water system--I'd have a few doubts about the wisdom of our investment in rainwater collection. If you add the cost of photovoltaic electric system, solar hot water plus other energy-saving gizmos and gadgets, the price tag of living off-grid likely will go over $50,000.

That doesn't include the cost of a wind turbine for generating electricity, a plaything I can't get out of my head.

The sizing of the cistern, approximately 130,000 liters, was based on the roof area and the amount of rainfall in San Miguel. According to friends Rick and Andrea, who have an even bigger rainwater collection system, 125,000 to 130,000 liters should be enough for a year without any heroic water-saving measures.

Design and engineering of the cistern, with its massive walls--as much as a four feet wide at the bottom tapering down to about half as much at the top--was the work of the architect. The house sits on a slope and we tried to take advantage of that to save some digging, and placed the cistern under a terrace. One of Rick and Andrea's cisterns is about 12 feet deep; ours will be only six feet deep but with a large footprint.

Our design turned out to be a smart move. The limited excavation we had to do became quite difficult when the jackhammer attachment of a backhoe ran into a nasty mix of dirt and rocks. The relatively new backhoe broke down several times during the rat-tat-tat digging.

The ungodly thick walls, according to the architect, were necessary because the unstable ground is mostly black dirt. Though they may look somewhat similar, San Miguel black dirt bears no resemblance to the rich soil you find in Iowa or other parts of the Midwest. Not only is the dirt here of very poor quality--its nitrogen content is particularly lousy--but its consistency ranges from concrete to mashed potatoes, depending on whether we're in the dry or the rainy season. Water also weighs a lot and the outer wall of the cistern will have to withstand considerable outward pressure.



If there's any good news in all this is that the prime building material for the cistern and the foundations is rocks, of which we have several hundred thousand on the property, of all sizes, shapes and colors. No need to ring the building materials supplier. Just tell one of the guys to go out with a pick and shovel and round up yet another wheelbarrow-full of rocks. We hope the magic of rain and soil shifting will help heal the pockmarked property.

The cistern is divided into three compartments, created by two walls needed to support the terrace above. Rainwater will mix with well water and run toward a low spot at the end of the cistern adjacent to a mechanical room under the kitchen. The system will use a submersible pump hooked to a pressure tank and water filtration system.

A couple of gringos who have built nearby have tested the well water though we haven't seen the results. Supposedly it is safe. We don't worry so much about amoebas and other creepy crawlies as we do about the potential presence of heavy metals such as lead, arsenic and fluoride. The creepy crawlies can be easily filtered out but metals are extremely difficult to clean up.

Heavy metals are starting to show up at some wells in San Miguel as some of the aquifers run low and pumps start to suck up dirt or contaminants become more concentrated. An analysis last year of most of the wells in the San Miguel municipality showed those in the Jalpa area to be safe, though our specific well was not tested.

Then there's the rain, about 20 inches of it annually, coming down in a single whoosh between July and October. We've been surprised how many people have warned against using rainwater for common household purposes because of "contamination." But in fact rainwater will run through a gravel and sand filter on the way to the cistern. It should be at least as clean as anything from our local well, in addition to being silky soft. The system will have a bypass to divert the first roof-washing rain and it does not collect rain from porches and other walking surfaces used by pets or humans.

This week we should start applying the finishing coat of cement inside the cistern. It's doubtful there will be enough roof area built by the time the rain starts and the fields turn green and the dirt underfoot resembles black mashed potatoes.

For her part, Doña Felisa already has warned, in her usual polite but serious manner, that there may be some reductions in service when the rains come in order to conserve water and protect our well.

Got to admire that woman. I doubt she's ever read any articles or books, much less attended lectures about ecological sustainability or any such thing. Yet she's figured out, all by herself, that in our semi-desert region water is a precious resource. And by God she is going to use the power of her position to make sure we don't waste it.

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