Heavy Metals as a concern for Vegetable Tires

I have been asked on several occasions if there is a concern about heavy metals leaching out of tires and affecting the vegetables. In short, the risk appears to be minimal.

Here is a somewhat longer answer. Your comments and especially any information you might have would be greatly appreciated.

If the question was about heavy metals leaching, I worked at finding information on that. The studies that have been done have been on shredded tires used as a base for play areas for children. I asked in ECHO, which has been promoting the use of tires and other basins for many years now. The consensus seemed to be that there have been no studies done on using tires for vegetable production, but that the risk is minimal (versus the advantages outweighing the negatives) because the tires are used whole, not shredded. That limits the surface area that is exposed to water/humic acids and also changes the physics of how water and humic acids interact with the surface area it does encounter. Also, at least part of any metals that might leach out would wash out with the daily watering, affecting the soil under the tires, but not the vegetables in the tires. Finally, we are worried specifically about heavy metals and heavy metals are not absorbed by most plants at all easily. The concern would be greater for vegetables that can (beets strike me as one that can absorb some heavy metals?) and particularly if those vegetables are grown consistently in the same tires. The odds would then increase that at least some of those crops are are contaminated.

Again, anyone reading this blog, please let us know if you have any information about studies that have been done. Martin Price at ECHO noted that one of the problems is that chemical studies like this are expensive and the people who use tires to grow vegetables are often poor, which makes it hard to find the funds to do the expensive studies.

Finding Water in the Mountains of the Artibonite

"Every time I think I have found the community that is struggling with the most difficult situation in terms of water, I find people struggling with a problem that is even harder."

The week after MPP's 40th Anniversary Congress, I went with my friend from Oregon, Susan L. Smith to visit some of our work in the mountains of Verettes in Haiti's Artibonite. Susan is a professor of environmental law at Willamette University in Salem, Oregon and a water justice advocate. She has worked with MPP (MPP website)for going on five years now, helping to provide funding and bring awareness of the need for clean water in the rural and disadvantaged communities of the Central Plateau. Susan is the Clean Water Leader for the United Church of Christ (UCC).

The Artibonite valley, with the majestic Artibonite river running through, is considered Haiti's "rice basket." While water is superabundant in the lower elevations of Verettes, it is can be extremely difficult in the mountain communities. Hosted by Nestly Voltair and other leaders of ODEVPRE (Organization for Development and Environmental Protection of Verettes), Susan was invited by ODEVPRE to see first hand the needs of the communities surrounding a spring known as Remonsaint. This site was about two and a half hours of tedious driving on a barely existent road. Walking, the community is about the same distance from Verettes, taking the much (much) steeper foot paths.

Susan Smith (blue shirt, red hat) visiting with the women and children patiently collecting water that slowly seeps into holes dug in the sand in this ravine. When I asked permission of the women to take this photo, they agreed without reservation, noting that the more people who know of their situation, the more hope they have that there can be change. Coordinates: N 18.99427, W 72.54382.

Trying to get some type of estimate for the number of people who depend on this site for their water, we asked the folks collecting water how many communities used this site. They listed for us about ten different mountain communities that come here during the driest months of the year (usually January-March). Then we asked about how many people live in each of those communities. The response that was a range. Folks estimated that the smallest had as few as 200 and the largest had at least 500. We took 300 as a possible average, which would mean that this ravine may be the main water supply for as many as 3,000 mountain inhabitants, for some part of the year.

Capping the Remonsaint water source. A Swiss aid organization, Helvetas (Helvetas) is helping the community of Remonsaint cap the spring and build a large cistern to store the water. It impressed me to find a non-governmental organization able to identify a need in an area as remote as this, and respond.

We spent a good bit of time visiting the folks working on the large cistern that will hold water from the spring and Susan and I were particularly impressed with one of the workers and a member of a local community (Terre-nette), Onondieu Louisius.

Onondieu Louisius from Terre-nette, one of the workers building Remonsaint's cistern. Onondieu helped explain the need for reforestation and the complications the communities face in following through with that need. Onondieu gave me permission to publish his photo on internet and to share his observations.

Onondieu was clear that the mountains of Verettes desperately need tree cover for many reasons, but especially to protect and increase the water supply for the local communities. He was also elegant in explaining some of the complications. Onondieu pointed out that because the area is remote and the road is so bad, trees grown in nurseries at lower elevations suffer too much by the time the reach the area around Remonsaint. That means that local tree nurseries are needed to produce trees that don't need to be transported long distances, and are better adapted to local conditions. But in an environmental catch-22, the lack of water during the dry season makes it impossible to establish a viable tree nursery during the dry months, which is when they have to be produced in order to plant them out during the rainy season. Onondieu noted that of course the area could produce trees during the rainy season, but said, " If we grow them during the rainy season, what will be the use of planting them out during the dry season? They will just die." He also noted that there are organizations that often come in and give away trees to local farmers, but they rarely come back to find out if the trees were planted, or if they survived.

Inside the cap. The bamboo is holding up the form until the cement dries thoroughly. Once the main part of the cap is formed, the workers will remove the bamboo and fill in this space.

At this point, at the end of March, the spring was providing very little water. As it begins to rain in the area, some of our sources noted that fewer people would be coming to get water, which would give the spring time to recharge and  to fill up the cistern. However, when we calculated the size of the cistern that is being built, we found that it would hold about 22.5 m3 of water, or about 22,500 liters. At 25 liters per person per day (the minimum per person used as a standard by the United Nations, according to Susan), the cistern would provide enough water for about 900 people, less than a third of the people who may depend on it.


As we left the spring, Susan observed, "Every time I think I have found the community that is struggling with the most difficult situation in terms of water, I find people struggling with a problem that is even harder."

African red worms doing their thing! Eudrilus eugeniae

Wilner Exil's red worms. From left to right, first hand shows the dried manure that we use as food for African red worms. The middle hand shows the worms at work and the third hand shows the finished product, full of worm castings. African red worms do an excellent job of turning dried, resource-limited cow, horse and donkey manure into a high quality, nutrient-concentrated compost. The worms reduce the carbon and concentrate the nutrients, increasing the microbial life exponentially as well. We also add a variety of green leaves to the manure to increase the nutrient value of the compost. We do not use kitchen waste because we have found that it creates a fatal attraction for fire ants. "Fatal" for the red worms, not the fire ants.The scientific name of African red worm: Eudrilus eugeniae

Hydraulic ram pump: Leodiagüe, Hinche (4th Section)

This past March 23rd, after MPP's 40th Anniversary Congress had ended, I walked up from Bassin Zim with Herve Delisma and Susan Smith to visit the hydraulic ram pump that Buzz and I and a motley assortment of others (see September 9, 2012 blog, Hydraulic Ram Pump) installed last August to serve the home and yard of Wilner Exil. Here are the photos with observations and the analysis provided by Wilner Exil.

Leodiagüe, and Hinche in general, is into its fifth month with just one bit of rain in January. All of the river and stream levels throughout the Central Plateau are low. The fact that the system is still working is a very good sign in terms of the viability of the stream, not to mention the ingenuity of Wilner and his family.
 

Bassin Zim, a couple hundred feet below where the community of Leodiagüe is situated. The waterfall is Bassin Zim, the river is Samana.

Two of Wilner's children, "Madanm" and "Ti Ben." They were my models for most of these photos, to help keep them from being just utterly mundane and uninteresting. They are sitting by the dam made from sandbags. Wilner reports that he had to reconstruct this dam approximately three times from when we first built it the end of August until the end of the rainy season in October. One of those floods was from Sandy.

Wilner reports that one of the most serious problems were the fish, frogs and generally the "kras" that would enter the 2" pipe. So one of Buzz's jobs (smile) is to help create a sieve that keeps the frogs out, but lets the water flow freely.

The 2" line going under a barbed wire fence (to the left). We used SCH 40 PVC, because we could not find a source of HDPE (High Density Polyethilene) flexible pipe in Port au Prince. This was the source of many of Wilner's problems.

Madanm posing for me by one of the makeshift joints that Wilner had to create as put the system back together after one of the floods.

Ti Ben sitting by one of the elbows that Wilner put in to replace the bends that Buzz created by softening the pipe in fire and bending it. Wilner said that the makeshift bends collected too many frogs, fish and other "kras," blocking the free flow of the water. So he sawed through them, cleaned them out and replaced them where he could with elbows, or with "akò," a piece that joins two pipes together. We originally used the makeshift bends instead of elbows because Buzz thought the 90º elbows might be reducing the water velocity and reducing the efficiency of the pump. One solution led to another problem.

Madanm at one of the remaining heat-treated bends.

An unintended bend, caused by flooding which tore the pipes out and lashed them against trees. The pipes were particularly vulnerable where the pipe bends awkwardly around the stream bed's curves.

Wilner showing where water is leaking out of a joint. Buzz left some higher quality PVC cement for Wilner to use, but when that ran out, Wilner bought the run of the mill variety available in Hinche, which did not work well as he tried to glue everything with water running through. This joint is what is called an "akò" in Creol. I always forget the word in English.

Another joint that leaks due to crappy PVC cement. On the right is the stand pipe which acts as a buffer to keep the water pressure in the system even and the pump working more smoothly.

The actual pump. The feedline is galvanized 1 1/2" pipe (to the right), the most expensive component of the system. Wilner Exil is leaning on the pressure chamber, which magnifies the force of the water running through.The other critical pieces are the one-way valve to the immediate right of the pressure chamber (horizontal) and the most magickest of the valves, the vertical one that lets water pour out until the velocity is sufficient to shut the valve and force the water into the pressure chamber, and from there up the delivery line, up, up, up the hill. (To the right of Wilner is Ti Ben, Herve Delisma and Susan Smith).

Wilner told us he has taken the pump apart several times to clean out the frogs and the fish and has got it back working each time. Buzz left the two pipe wrenches he had purchased with Wilner to make sure he could do that.

The pay off. Close to hundred feet above the pump (elevation), the water trickles into this barrel. We measure the flow using a 591 ml bottle which took 2.75 minutes to fill. That makes for about 12.9 liters an hour, approximately 3.3 gallons, or about 79 gallons a day. (If we made any errors in our calculations, please let us know.)

3.3 gallons an hour does not set the world on fire, or, I guess, would not put out a fire that was set. But the pump works continuously (when not blocked by frogs, fish and other "kras") for free. No additional fuel or electricity costs, and 79 gallons a day of relatively clean, and relatively labor free water is nothing to sneeze at. Its to water plants with!

Also worth noting is that Leodiagüe, and Hinche in general, is into its fifth month with just one bit of rain in January. All of the river and stream levels throughout the Central Plateau are low. The fact that the system is still working is a very good sign in terms of the viability of the stream, not to mention the ingenuity of Wilner and his family.

Here is a summary of the problems that Wilner noted that Buzz (and us) will need to work on:

1) Each time the stream floods, the dam has to be rebuilt and the pipes put back together. In terms of the pipe, the particular vulnerability are the joints which always end up crossing catercorner to the flow of the stream. The 2" line bringing the water to the feedline is particularly troublesome, but the 1/2" delivery line, where it crosses the stream, is also a problem.

2) Putting the pipe back together dry is very difficult, and the Hinche-available PVC cement does not work on the wet pipe.

3) Because of constantly putting the system back together, the elbows and the "akò"s are costly. The system as it is also needs a couple of new 2" SCH 40 PVC.

Despite all the problems and the periodic labor, the system is working and providing a valuable product that is used by two or three households. The question is clearly not whether it is worth it, but how to improve it to function more efficiently and with much reduced ongoing costs for materials and labor.

Most of the problems with the system can be eliminated, or at least reduced, by finding a source of High Density Polyethilene flexible water pipe.