Ecological System Designs for the Indigenous Community of Maruata, Michoacan, Mexico

Maruata's primary resources- a fairly intact ecosystem...

Following turtle tracks in front of our tent.

The tortugero Bubba and Dave built.

Showing off newly hatched "negra" turtles ready for release.

Pozo a couple of paces from a river of dilute fecal matter. Amazingly, when freshly dug the water is clean due to filtration of the sand (water test results #m35). When the groundwater level changes, the well is re-dug.

Noria in town. The owners said the water was good to drink for a year or two after they built it, but they didn't use it for drinking when I took the picture (16) and they abandoned it and filled it in a year later. When the rains really hit, the entire surface of the ground is ankle deep in pig-shit laden water (24), which pours down into the pozos and norias alike.

Animals also crawl into norias and die there (2).

My first choice for a drinking water source was a pipe network from gravity-fed spring water (7). The difficulty is that the monsoon unleashes such a deluge of fecal-matter contaminated runoff (27) that it is very difficult to completely protect a source.
This source, which is used by houses a half hour walk from town, we helped protect by facilitating the construction of a rock wall to divert surface runoff.
A pipe network for drinking water is also extremely difficult to maintain sanitary under third world conditions. A cyclone scoured away some pipes buried 1 m (40") deep two years after they were installed! Additionally, typical third world water systems don't have pressure all day long, and have many leaks. When there is water, it leaks out and forms puddles on the surface.

When the pressure drops (which happens multiple times per day) the puddles of street dreck are siphoned back into the pipe and will be the first water out of the taps when pressure is returned.

My second choice was containers filled at the source with spring water in the dry season then rain water from the biggest, cleanest roof in the wet season. However, testing showed that all roofs are coated with feces dust during the long dry season, and even after several inches of rain the water is still contaminated (28).

The villagers do collect rain direct from the sky in clean pots when it's dumping rain, and this works well.

Finally I decided that a tube well to the clean, good tasting groundwater right underfoot would be the most dependable source of water clean enough for the locals to drink in all conditions and even to sell to the softest tourists. (I have observed that hardy locals seem to do fine with water containing 50 ppb of fecal matter. I can handle about 10, while the softest tourists can get sick on anything over 1ppb).

We had an interesting time trying to figure out how to jet a tube well. If anyone knows how to do this efficiently on a small scale, please Email us .

After temporarily giving up on jetting a pipe the whole 6m, we found an abandoned noria in a really good location to convert. The earth in this spot is a cap of relatively impermeable soil a few meters deep. When they reached the sandy earth underneath that, the water boiled up under pressure, rapidly rising two meters. The well is on the property of one of the water system volunteers in town. After the original construction, the noria did the usual downhill slide, hastened by the cracking of the seal (above) and the partial collapse of the culverts, which let soil and runoff fall in wholesale.

To convert it, we first bailed many buckets of anaerobic black muck and "things" out of it, then pumped it clean with a 1" electric pump and a two inch gas pump.

Then we jetted a 3" PVC pipe a couple meters into the floor of it (the pipe shown is a full 6 m, so that's the depth). We then packed the space with sifted gravel (sifting shown above). A couple meters of coarse gravel were followed by the medium, then the fine.

The fine gravel was overlain with a meter of sand, then a meter of clay.

The clay plug at the top makes entry of surface water very unlikely.

The clay was overlain with a concrete cap 2 m (6ft) in diameter. This cap extends well past the original excavation onto undisturbed ground (the first cap broke when the lining settled). When the well was completely sealed, we poured a few cupfuls of chlorine down it and let it sit for a day to zap any lingering nasties. Then we pumped it for several hours.
With a 1" electric pump, the water level drops a few inches, then holds steady indefinitely. It is important that the pump not suck air, as the water used to re-prime it could introduce new contamination.

Al paticuzie mushtin --Nahuatl for "water good to drink for the people"

The concrete was kept moist for a couple days against cracks. Even with ankle deep monsoon runoff everywhere this water will still be good to drink.

The easy part has worked out well; the water has consistently tested at "non detected" for coliform bacteria, which is better than the bottled water (it typically has one or two general coliforms per 100m).

Now the hard part begins...enticing the villagers to use and maintain the system. The current idea is a public/ private partnership with the landowners and village.

Manual welding the lockbox for collecting resident's contribution's at the garafon filling station.

Storage for fifty garafons with filling hose and bench.

Testing the water with Coliscan Membrane Filtration and Hach presence/ absence tests. The coliform levels from the drinking water well were consistently lower than the purchased bottled water, and frequently zero coloforms per 100 ml, which is a lower level than that frequently found in bottled drinking water in the US.

Water test results- Maruata
Fecal coliform counts

Repair of the old community springbox…surface water carrying livestock feces was entering through numerous holes. A fence was installed around the spring area to keep animals from camping out on and around the springbox-especially popular during the dry season.

The excavation of the new springbox…this area was a swamp frequented by livestock, now kept at bay by the perimeter fence. The new springbox doubled the communities' water supply.

Bubba Walker laying blocks for the new spring box; actually a thirty foot long horizontal well.

The finished product...

At least half of the water that makes it to the storage tank above the town is then lost in leaks and overflowing water tanks downstream. We've helped train some water volunteers to fix leaks in galvanized and PVC, and outfit houses with valves. Float valves on the private water tanks (shown above) would be great, if we could get them to last.

The bike I designed for my use while working on the water system. It is outfitted with an altimeter and distance meteorite survey the lines and hooks to carry long pipes for repairs. I later added bins to carry wrenches and fittings.

Digging trenches to prevent contaminated surface runoff from entering the El Chorrito spring complex.

Planting trees along the berms from the trench tailings will stabilize them against erosion.

When the fence posts rot out, the lline of new trees will serve as fence posts.

Wildcrafted seeds of native hardwoods.

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A local kid planting seeds along the watershed boundary above his house.

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The 2003 reforestation team (read a story about their work).

The view from the ridge above the spring. Note the river bed, which was a shaded, narrow deep channel before the road and deforestation arrived—it is now a few hundred meter wide sunbaked sand bar.