Reclaimed water, the last hope for the Canarian banana

The farmers of Punta del Hidalgo, in the north of Tenerife look at the sky with concern. There, the drought suffocates more than the absence of rain. The lack of water in the aquifers increases the cost of “clear water” and the stifling heat has forced many to throw away their crops, which mature before their time. The situation is such that the Cabildo was forced to declare a water emergency on the island on March 1. «Before, a lot of water came down from troughs, but less and less. Let's hope it is a cycle and that it will be reversed in a few years,” says farmer Juan Mesa before a group of media, from near his farm. He has been working in the field for 15 years. His neighbor Diego González also grows bananas; In his case, for about 20 years.

The altitude of the municipality allows you to obtain magnificent views of Teide. From the top to the bottom, the area is full of agricultural crops and palm groves that cover the slope. But the water does not slide from La Punta. Adding to the problem of desertification is the remoteness of this part of the island from the public irrigation network. «The only thing here is an obsolete canal that is a century and a half old and has many leaks. There is a broken section and farmers do not have the financial capacity to replace it. We depend on some aquifers,” explains Juan, whose farm has 15 hectares. This situation led him to join in August an initiative developed between the Insular Water Council, Teidagua and Coca-Cola, which has allowed him to irrigate his plantations with regenerated water treated at the Punta del Hidalgo treatment plant.

“This project has come to us like rain, because the tensions are increasing,” says the farmer. For now, reclaimed water is enough to cover 30% of its needs and, although it does not solve the problem, it has helped relieve pressure on aquifers. The objective is to increase the percentage. Currently, the station is undergoing modernization works and, at the end of 2024, it will go from 40% to regenerating 100% of urban water.

This will allow 91 hectares of 17 agricultural farms to be irrigated, as well as recover farms abandoned due to lack of water. It will not be enough: “We made a calculation at the beginning of the project and it was estimated that with 100% of the water from the treatment plant still being regenerated, they (the irrigators) would need 25% more water to cover the entire area,” comments Eduardo Alemán, Teidagua technician, but “it's a relief.”

Furthermore, this work – intended to install the latest ultrafiltration technology available – will make the quality of the water obtained by farmers “supreme.” According to Alemán, it is already very good, because the system they have even eliminates nematode eggs. The only thing missing is to reduce the conductivity given the regenerated waters, which determines the appropriate level of salts for irrigation. For papaya there is less of a problem, but banana is more delicate. In any case, more and more farmers are using it. At first, only four joined. Now, there are 18. In Teidagua they predict that, when this indicator is lowered, “interest will grow exponentially.”

More than 2,000 irrigators

In the Valle de Guerra, also in the north of the island, there are already 2,000 irrigators who benefit from the regenerated water in the area's treatment plant, which already has an innovative ultrafiltration process by electrodialysis that reduces the content of dissolved salts in the water, regenerating with the highest quality. This is where the wastewater that results from the production process of the Coca-Cola factory in Tacoronte ends up. After undergoing a demanding treatment, the liquid allows the irrigation of an area of ​​350 hectares of tropical crop land, especially bananas.

These projects are of great relevance for the area, since the Tenerife agricultural sector is experiencing difficulties due to the limited availability of water. The reclaimed water complements the groundwater from wells and galleries that farmers access through the private market. In fact, it becomes even more economical, according to Teidagua, this being one of the greatest achievements of the project. The possibility of having regenerated water for irrigation that saves costs for farmers means ensuring the viability of crops, but also strengthens the socioeconomic viability of the area.

Diego has a three-hectare plantation and, together with Juan, owns one of the largest farms in this part of the island. The problems they face are many: “The banana is not only sold at a loss, but it is thrown away so that the price does not collapse,” he laments. Many are donated to the food bank or given to animals. It is clear that the problem is temporary, but this initiative, for them, has been like drinking fresh water in the desert. “When we found out what would be done in the treatment plant, we almost toasted with regenerated water,” Juan jokes. That says it all”.