It is always exciting to see how Vetiver can be applied so successfully to resolve a problem, and its versatility in application. The preceding blog showed its use for extreme slope stabilization. This blog will address how just a few Vetiver plants can be used to "scrub" highly contaminated water in California. The work was carried out by Bio Clean Environmental Services at Ocean Side, California. This company specializes in storm water treatment. Zack Kent, Storm Water Engineer, writes: "The Ocean Side project was an interesting situation because it treats wash down water from a harbor boat wash site, along with many little sewer spills coming from recreational vehicles (RVs) on a continuous basis. It’s a very dirty site. We have removed over 4,000 pounds of oil laden sediment from the pre-treatment chamber in the last two years. The system treats 2,000 to 8,000 gallons of water every day. We chose Vetiver grass because it has the ability to grow in saline water, which we have there all the time, and the ability to deal with high pollutant loads which we also have at that installation. It was a great choice and a real success story." There is a power point that contains images and data about this project on TVNI's website. Also a very good field report with images prepared by Michael Alberson and Tim Klein
The Vetiver (approximately 18 plants) was planted in a concrete treatment box in a special media "One of the ways we get the Vetiver to grow so quickly is we don’t use any soil. It’s a soil-less media made consisting of expanded aggregates and a proprietary hydroponics media. This allows for fast growth." Over a period of 15 months the plants put out a massive root system, and in doing so resulted in high uptakes of N, P and a range of heavy metals.
The key data included removal efficiency when comparing effluent inflow to outflow: nitrate 76%, phosphate 70%, TSS <15 microns 82% , copper 53% (undetectable), lead 100%, Zinc 79%, TPH (gasoline) 42%, TPH (diesel) 100%; TPH (motor oil) 100%, fecal coliform 84%,E. coli 79%, and Enterococci 70%
The Vetiver was trimmed at intervals, and was dug up after 15 months
Here follows some images:
The Vetiver (approximately 18 plants) was planted in a concrete treatment box in a special media "One of the ways we get the Vetiver to grow so quickly is we don’t use any soil. It’s a soil-less media made consisting of expanded aggregates and a proprietary hydroponics media. This allows for fast growth." Over a period of 15 months the plants put out a massive root system, and in doing so resulted in high uptakes of N, P and a range of heavy metals.
The Vetiver was trimmed at intervals, and was dug up after 15 months
Here follows some images:
These results support Paul Truong's data developed in Australia and once again confirms the utility for vetiver to treat contaminated water.
So it would be interesting to know if any of the community leaders saw this and have any comments. Getting the idea into the city planners agenda would really lead to a wider use and make it sustainable. Have you tried to contact them with these results. The really interesting thing is that the system only needed 18 plants and it was able to handle thousands of gallons a day. The pictures are a story unto themselves. If only others would be tempted to do the same.
ReplyDeleteA reminder why vetiver is so good for this application. Paul Truong's research in Australia showed that vetiver can take up and tolerate as much as 10,000 kg/ha equivalent of nitrogen, 5 times more than most other plants. He and others have shown the remarkanle ability of vetiver to sequester and tolerate high levels of most heavy metals.
ReplyDeleteAnother comment: Some interesting work was carried out at Aceh, Indonesia after the Tsunami. Effluent from some 2000 houses was treated on an individual house basis using a fairly simple vetiver system set up. See: http://www.vetiver-indonesia.com/index.htm
ReplyDeleteCould be useful in the reconstruction of Haiti
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