A Mexican engineer has succeeded in keeping plant roots hydrated for several months by trapping water in a solid form. The technique offers a decisive tool in fighting against drought, and won the inventor the world water prize in 2012.
Sergio Jesús Rico, an engineer from the National Polytechnic Institute (IPN), was determined to find a way to provide a supply of water to crops that eliminates the problems of infiltration and evaporation. The solution was potassium polyacrylate: a chemical substance capable of adhering to plant roots that stores water by transforming it into a gel.
Nicknamed “solid rain” by Rico, the substance takes the form of a white powder that looks like similar to sugar. Each kilogram can gel 500 liters of water. Rico says that potassium polyacrylate can be used with any kind of plant, including pasture and forest vegetation, greenhouse plants and especially food producing plants.
A comparative study conducted in the state of Jalisco demonstrated the incredible efficiency of the new technique. Whereas traditional irrigation of corn yielded 600 kilos per hectare, the solid rain product provided a yield of ten metric tons per hectare.
Based on pilots conducted in Colombia, the quality is there. The blocks of water are placed undergorund, and they replenish themselves after each shower. Using this method the irrigation-related costs dropped by 75% while foliage and flowers increased by 100% and the roots by 300%. In India, for certain crops normally needing 80 litres of water per month, the technique allowed irrigation to drop to 50 liters every 3 months.
With a useful lifetime of between 8 and 10 years, potassium polyacrylate enables the development of more economical new irrigation systems, particularly in drought zones.
The development of solid rain helped Rico win a nomination for the World Water Prize 2012, a prize awarded by the Stockholm International Water Institute.