Lack of water threatens agriculture from Maule to Biobío
The deficit reaches 60% in the south central zone, rivaling the great droughts of 1968 and 1998. The big difference is that now there are strong investments in fruit and industrial crops which imposes a greater demand for water. The lack of accumulation systems means that much of the winter rains are lost and conflicts over the management of lagoons and reservoirs complicate irrigation planning.
Margarita Letelier, Ñuble's farmer, will leave this year uncultivated near 500 of the 900 hectares that she usually sows with beet, wheat, corn and blueberries.
He knows he has no choice. The year comes dry and, if you sow the whole surface, you will not be able to water it. The above because at this time of the year all the parameters indicate that there will not be enough water or snow to cover the entire agricultural area of the area.
"We have a deficit close to 60% and if it continues without raining the water shortage will only increase"says Margarita Letelier, who is also the president of the Ñuble River Surveillance Board.
In fact, the 2016 is one of the driest years in the area. Even statistics show that last June was the second with less rainfall since the 46 year. “We are facing a scenario as dramatic as that of 1968 or 1998 (which are the worst reference droughts), but with the aggravating circumstance that it is the eighth year with rainfall below the historical average. That means that a bad year catches us without reservations”, says José Luis Arumi, dean of Agricultural Engineering at the U. de Concepción, and researcher at the Center for Water Resources for Agriculture and Mining of that house of studies.
A little further north, in Region VII, among the farmers and irrigators of the Maule, the specter of water shortages in the coming months, precisely the priority ones in terms of irrigation, already leads to talk of restrictions and urgent calls to reduce water sowing areas and to evaluate in advance to what they will use the water that actually touches them.
In both areas, it is said that the water conditions are worse than the droughts of the 68 and 98 years, with the aggravating circumstance that in those times the water demand of agriculture was lower.
It is that while still expect some spring rains, the measurements of water and snow are not rosy.
The last measurement of the General Directorate of Water is clear for both regions: the snow accumulated in the mountain range is much lower than what would have to be at this time of year. And, even worse, due to its characteristics, it will thaw very fast. This leaves in evidence a structural problem of the two regions: they do not have enough accumulation systems to allow the water that fell in winter, nor the anticipated thaw, to be saved.
The situation is even generating tensions among the irrigators themselves, who, especially in the area of Maule, are divided against an agreement with Endesa for the use of the waters of the lagoon.
The Maule crisis
The situation of the Maule basin is critical, experts say.
According to the latest DGA measurements, the region has a 46% rainfall deficit, with an average of 428 millimeters of falling water during the year. If that is compared to 2015, when there were 664 millimeters of falling water, the deficit is 36%. It must be considered that the past did not come with less water than normal either.
The drama does not end. The height of the snow in the area of the Maule lagoon reached the 0,80 meters at the 31 in August, which contrasts with the 2,51 meters of the 2015 year on the same date. And that is key for the season.
“That marks the durability and time of the thaws, which are what keep the rivers with enough water for irrigation. When there is little snow they do not have enough. On January 7 of last year, the basin declared itself in deficit. This year, the situation would lead to declaring that measure five weeks earlier. That implies watering a lower percentage than usual. That is why each producer has to consider very carefully the spring crops that he is going to do. This is a very critical year and it is a difficult situation to handle. Anything that involves driving to save is important”, says José Manuel Silva, of the Maule Canal Association.
In the region, the only accumulation work for irrigation is the Maule lagoon. According to the agreement signed in 1947, when it was transformed into a generation and irrigation reservoir, about 80% of the water belonged to the State, administered by the Ministry of Public Works through the Directorate of Hydraulic Works (DOH), and its priority destination is irrigation. The remaining 20% is owned by Endesa.
Therefore, what happens with it is key to an essentially agricultural region, with more 220 thousand productive hectares.
At the end of 2015, after five years of drought, the level of the lagoon did not stop decreasing and at the end of that year the level reached its minimum level, that is, the remaining water was only available for emergencies.
At that time, the Maule River oversight board, in charge of managing and distributing the waters of its users (which include about 60 canals, electricity companies and other industries, proposed an agreement to make the operation more flexible with the aim of increasing accumulation of water in the Maule lagoon.
For this, the farmers would irrigate with water from the La Invernada lagoon, owned by Endesa. That water would be returned with that of the Maule lagoon, at a rate of 0,82 liters for each liter used. The differential, argue the irrigators, would accumulate in the latter, to which the water from the winter rains would also be added, thereby increasing the level. Endesa, meanwhile, gained by lowering the costs of its operation, since in order to generate with La Invernada -which is 1.300 meters away- it has to raise the waters to 2 meters from that of Maule and thus count on the fall necessary.
However, some irrigators and farmers, including Agrícola Central, Talca's main producer association, saw no benefits in the formula.
"The agreement was bad"says Fernando Medina, president of the entity, who maintains that in practice it does not imply real savings for irrigators. One of the reasons given is that the La Invernada lagoon has leaks that cause part of the water to go directly to the channels, that is, “they would have been equally available to the irrigators. For the same reason, it is difficult to gauge how much water was actually removed. For all of the above, the return of 0,82 liters would not be meaning a real saving ", He says. And he adds that “If the agreement implies an additional contribution, let's discuss it. But, with the economy that is proposed, the level of the Lagoon does not increase”, emphasizes.
The irrigators, on the other hand, consider that the option was viable. “The operation was applied last summer. Savings could be made and that water is now in the lagoon”says Silva.
But the division had consequences. The agreement had to be ratified by the Minister of Public Works Alberto Undurraga. After trying to reconcile positions, he finally chose not to ratify it, even though, in the resolution, he acknowledges that it had worked very positively.
Carlos Diez, president of the monitoring board of the Maule River, questions the decision. “This season we will not be able to make agreements with hydroelectric companies either. Minister Alberto Undurraga seriously harmed us by not endorsing the agreement that the Hydraulic Works Department (DOH) had made with Endesa and we will not count on them as strategic partners. Therefore, we will have to continue removing all the water from the Laguna del Maule, depleting our main reservoir."
They call to restrict themselves
The previous put a new pressure to the shortage of rains and snow of this season.
“The problem with the non-approval of the agreement is that it takes away tools from the Surveillance Board to make better use of the water in the season. With this, the deficit becomes doubly dangerous”, emphasizes José Manuel Silva.
The irrigators insist that the water available in the lagoon is not enough for the season and they call for everyone to take saving measures.
“We cannot think that the lagoon has the capacity to deliver water to us in the months of deficit. We have to save water when there is. And that has to be done both at the individual level and the Oversight Board. The only way is that, if an irrigator corresponds to an amount in spring, use a lower percentage and save for the most complex moment”comments Felipe Olivares, advisor to Maule.
In any case, under current conditions, the forecast is that the restrictions will be around 30% in December and of the order of 35-40% in January. "This is to be able to irrigate, but always thinking of a smaller surface, because what is there is not enough for the entire system"comments Carlos Diez.
This does not mean that everyone will receive water in those percentages. While in general in the large channels the distribution is relatively fluid, with the smaller ones the subject gets complicated.
“The theory indicates that it has to be distributed pro rata, but not everyone has an optimal infrastructure to do that, so the distribution is not as efficient as theory indicates. There are some channels, for example those of the northern Maule that are very long. Due to the inefficiency of the canal and the poor condition of the infrastructure, it is most likely that you will arrive with water in your head, but not in your tail…”, explains Olivares.
The brake in Ñuble
In Ñuble and Biobío, the safety of irrigation has been one of the causes of the shift from traditional agriculture towards an intensive one, in which the arrival of blueberries, hazelnuts and cherries already changes the landscape. However, irrigation is also the concern of farmers this year.
"Water availability for the season is going to be tight and it is going to force us to have an exceptional strategy to get ahead", comments Héctor Sanhueza, of the Association of Canalistas del Laja.
According to the measurements of the Ñuble River Surveillance Board, rainfall in recent months has been well below that of a normal year. For example, in a normal year, in June they precipitate between 180 and 190 mm. This 2016 only dropped 10,6 mm. In other words, the deficit was 94%. And although in July it was compensated and average values were reached, in August, the deficit with respect to the same month of a normal year was of 70%, with only 44 mm versus the 130 mm of a normal year, says Salvador Salgado, manager of the Ñuble River Surveillance Board.
According to the data of the DGA, in the province of Ñuble, to date have precipitated 577,1 millimeters, which would be a 19% less than last year at the same date. This would be about an 43% more water drop than in 1998 (403,7 mm).
The problem is that 85% of the rain that falls in the area is between April 15 and September 15. That is to say in winter there is water ... but, the agriculture needs it in spring and summer.
As in El Maule, in this area is a lagoon, that of Laja, the main water accumulation infrastructure. And according to the measurements at the end of August of the General Water Directorate of the MOP, it presents 26,4% of its historical average and 15,7% of its capacity, with a volume dammed, to the 31 of August, of 878,2 million of cubic meters.
The hope that it will increase due to thawing is fading: the Volcán Chillán station registers 15 millimeters equivalent in water and the Alto Mallines, in the Ñuble national reserve, accumulates 147 millimeters equivalent in water. Compared to last year, they present a deficit of 97% and 71%, respectively, according to data from the DGA.
The waters of the Laja, as in the Maile del Maule, are managed by an agreement, in this case of 1958. Given the water shortage, different users have been establishing agreements, albeit transitory, especially between Endesa and the irrigators, or rather the DOH, on behalf of the State, which is the one that administers the waters for irrigation.
This agreement seeks that the electricity generates when it is required to water, that is to say in summer and not in winter. “If it is generated in autumn and winter, it does not accumulate, since the water continues on its way to the sea. On the other hand, if it is done during the irrigation season, Endesa generates in the same way, in the same amount, through the same outlet, but later the water can be used, so there is a double use. With this, only the time of year to open the floodgates changes”, comments Juan Carlos Villagra, president of the Diguillín River Surveillance Board.
The last of these transitory agreements expires November 30 and they are in full talks and refining details to try to renew it.
This increases the anguish of this season. “Irrigation for this season becomes very complicated if the temporary modification is not made or we do not make a definitive agreement. This will mean that everyone will fully want their rights and the current amount of water in the lake does not support it. That can have a very strong impact on the season. It's a very difficult scenario.", emphasizes Sanhueza.
In the face of scarcity, as in Maule, the call is for farmers to take the necessary precautions.
“The upcoming season is going to have lower availability than last season, which was already complex. That leads to think that farmers have to take the shelters, understanding that it will be a complex year ", insists Salvador Salgado, of the Board of Vigilance of the Ñuble River.
The underlying problem
The irrigators, both Maule and Ñuble, also recognize that there are no options: climate change altered rainfall and everything indicates that the rain will not fall back in the same volumes as before, which is already affecting the flow rates.
“In 83 the average flow of the river was 110 cubic meters per second. In the 2015-2016 season, it had around 80 cubic meters. This is talking about the fact that it is a situation that remained. It's been close to three decades with a downward trend.", emphasizes Salgado.
For this reason, irrigators and farmers insist that beyond the drought and the specific polemics of this season, what is clear is that the underlying problem is the lack of accumulation infrastructure that allows the water of the rains. This is important because it is clear that the snow is not falling as before, both because it falls less, and because it does in higher areas.
“Today there are reservoirs that belong to hydroelectric companies. Last year no water was taken from the Laguna del Maule, due to the agreements made with Endesa and Colbún. You have to keep doing that because it's the only way to get it back. We all have to unite and support the authorized institutions”, says Silva.
For now, new infrastructure projects are being planned, such as the Punilla and Zapallar reservoirs, but the forecast is that they will not be ready before seven or ten years. And this may be too long, especially considering that in a hydroelectric power station they have them running in terms of around two years.
A second aspect that is clear is the need for all water users to work towards a common goal. However, the problem is that interests do not always coincide.
“It is clear that the irrigation infrastructure needs to be improved. The other great lesson is that it is necessary to reach agreements with non-consumptive users of water. They have things to offer so that these scenarios are not so hard "says Olivares.
For the same reason, Medina insists that a rational watershed management proposal is being worked on to allow more efficient use by all the actors. "If a use is achieved in a coherent and rational way, we should be able to pass this drought and those that may come in the future"he insists.
In the Laja, meanwhile, a table of water that includes the MOP, the electricity, the irrigators and the Chamber of Tourism of the Salto del Laja. “In the framework of that table we are working on two major fronts. One is to look for a way to adapt the 1958 agreement and in the construction of a Surveillance Board. There is expression of wills of all parties. It is not an easy subject because there are many interests involved”, says Sanhueza.
Many look at what has been done at Laja as an example of coordination between different users.
“This association between generation and irrigation should be throughout the entire country. It is logical that there are good agreements between the different economic activities. It would allow optimizing even future infrastructure investments. The country has water, what you have to do is use it properly and in a coordinated way” emphasizes Villagra.
Finally, the other aspect is to plan the use of the land, considering the effective availability of water.
“There is increasing demand and the availability of water decreases. There is a lack of planning and ordering to carry out a more projected work in terms of land use and, therefore, of water... It must be considered that it is the same supply. So, it is necessary to carry out a macro analysis of what the real availability is and to be clear about what it is actually enough for. And the same goes for aquifers. The authority has not declared a restricted area for them. The situation is unknown.", says Salgado, referring to the fact that the demand for groundwater in the area also increases.
The concern is that the agro can express its full potential and that the water does not become a constant sword of Damocles.
“My family is from the countryside. My dad always told me that his concern was the water. I met Santiago many years ago. And today I see that in Chillán it is raining the same as it fell in the capital 15 years ago ”, says Margarita Letelier.
Restrictions of up to 40% on water supplies will be applied in the Maule.
Source: Field Magazine
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