We can’t resign ourselves to losing Lake Cocibolca

The following statement cost Salvador Montenegro his job as director of CIRA, founded by him in 1980, thanks to the governing party political operatives’ intimidation of the professors who had to decide whether he would keep it or not. Despite this “punishment,” Montenegro again called the canal megaproject “despicable” for its attack on the country’s most important natural resource, declaring that remaining silent about the risks would be “high treason against one’s country.”

Salvador Montenegro Guillén

Very much in line with Comandante Daniel Ortega Saavedra’s urging in June 2012 that the design of the Great Interoceanic Canal must be “conceived and executed well so as not to affect the environment,” Salvador Montenegro took both personal and professional responsibility for warning anyone willing to listen about the unnecessary risks Nicaragua was taking by wasting its best natural social, economic and environmental development option, i.e. the waters of Lake Cocibolca, also known as Lake Nicaragua.

The best and most sustainable
project for Lake Cocibolca

Besides being the greatest reserve of fresh water in Central America, supplying drinking water to our growing population, another virtuous use for Lake Cocibolca’s water has now been identified: the ability to irrigate the country’s western plains. The study “An Irrigation Strategy for the Pacific Plains of Nicaragua” considers the lake’s waters capable of irrigating some 625,000 hectares along the Pacific area.

There have been various attempts to give shape to this project, conceived five decades ago. It was formally presented to the Soviet Union in 1985 as a potential project, but without success. It was again considered at the People’s Summit in Cochabamba in 2009 when President Ortega announced the good news that the fertile soils were going to start being irrigated with the lake’s water to produce food for Nicaragua and export the surplus.

This excellent initiative, together with using the lake waters to provide drinking water to the most populated areas of the country, would be the best and most sustainable use of Lake Cocibolca. Irrigating the country’s still underutilized fertile western soil would be a panacea for Nicaragua’s social and economic development. It would allow us to strengthen our country as never before by producing food for our people, exporting the surplus, developing agribusiness to add value to our crops and employing thousands of people who are now working the fields of neighboring countries but would return to Nicaragua. Lake Cocibolca could supply some 60 meters of water per second to irrigate a vast area, and would be a sustainable environmental investment. No other country in the Americas today has a similar resource to that lake.

Drinking water for everyone
and irrigation on a grand scale

Utilization of Cocibolca’s waters is inextricably tied to protecting the lake to assure ongoing sustainability. It is thus crucial to keep in mind that this great jade-colored oval can’t be viewed with the covetous eyes of Cornelius Vanderbilt or of William Walker, for whom the lake was only a means to their ends.

Fresh water is a prime natural resource and a key factor in development. Nicaragua has what it needs with Cocibolca and must not risk this resource. Our Lake Cocibolca is not just the largest tropical lake in the Americas but, according to Law 620, the General Law of National Waters, is also considered a strategic drinking water reserve for the country.

Of all the Nicaraguan bodies of water, subterranean or superficial, only Lake Cocibolca can satisfy in quality and quantity the needs of our growing population, which will reach 10 million people in the next generations and will thus need 691 million liters daily. With low-cost treatment, the quality of this lake’s water would allow for this use. In addition to the increase in demand for drinking water, food demands will also increase and will need to be filled by irrigating crops to lessen the dependence on irregular and unpredictable seasonal crops, especially with today’s variable climate conditions and climate change.

I’ve mentioned only the most important uses of Cocibolca’s water i.e. drinking water for all and large-scale irrigation. Both these uses—crucial for national development and well-being—are still diamonds in the rough, and both are particularly sensitive to the presence of contaminants in the water. In Central America, with its progressive desertification problem, the mere fact that Nicaragua has water gives it advantages and additional options for its socioeconomic development.

The canal is feasible but
lacks environmental sustainability

There are enough factors and previous experiences to roughly foresee the consequences the Great Interoceanic Canal Project will produce if its route goes through Lake Cocibolca. The project under consideration today is essentially the same design conceived of 130 years ago by Admiral E.S. Wheeler of the US Army Corps of Engineers and A.G. Menocal of the Nicaragua Canal Construction Company, which included excavating a channel through Lake Cocibolca.

We are thus obliged to carefully analyze the risks this would have, not only with respect to its effects on using Cocibolca’s waters for drinking and irrigation, but also to the project’s financial and environmental sustainability. The risk of collapse is great if the environmental conditions that prevail in this body of water are ignored. Independent of the commercial and construction feasibility of this massive project, its environmental sustainability presents very low probabilities of success if its route includes Lake Cocibolca, risking a collapse of the initiative in the medium run and with it an economic, social and environmental tragedy for our country. The project’s design conception, based on the inevitably static design done in the 19th century, must necessarily consider the dynamic of the natural processes.

More than a century ago
the lake was navigable

Lake Cocibolca is an extensive lake with a variable area that, historically averages 31.10 meters above sea level and exceeds 8,200 square kilometers in breadth. It is surprisingly shallow, averaging only 12.5 meters deep. To put it in perspective, this mass of water is like a delicate covering over a very flat valley. It receives some 18-20 million tons of sediment every year and is subject to constant wind action.

Navigation through the Transit Route, developed for Cornelius Vanderbilt’s steamships in the mid-19th century, consisted of successive relays along the route that crossed the lake, using different boats and multiple transfers of merchandise and passengers to be able to cross from one ocean to the other. Improving on this slow process, the canal designed at the end of the 19th century sought to build a secure navigation method for seagoing ships across the isthmus that would enter through Greytown in the Caribbean and through Brito in the Pacific and would navigate through Cocibolca Lake and exit on the opposite side.

According to the 1885 design, allowing for the crossing through Cocibolca of deep-draft seagoing ships required dredging the lake’s minimal depth of only 9 meters by excavating a channel 60 meters wide and 90 meters long at the bottom of the lake. It didn’t need to be done at the time because ships like the “Victoria,” which sailed from Delaware to Granada in 1883—displacing 150 tons of water—measured 45 meters long and 9 ½ meters wide but less than 2 meters below the waterline. Had it not had this shallow draft, it would have been unable to navigate the Cocibolca. Other steamships used by the Vanderbilt Transit Company, such as the “San Francisco” and the “Hollembeck,” had similar draft depths and thus could to cross Lake Cocibolca’s shallow waters.

If sediment is the
canal’s great challenge..

The serious erosion of the basin in which Lake Cocibolca is situated means the continuous deposit of millions of tons of sediment each year from its drainage area according to the World Bank’s 2013 study, “Policy and investment priorities to reduce environmental degradation of the Lake Nicaragua watershed (Cocibolca): addressing key environmental challenges.”

The need in 1890 to dredge and excavate a channel in the lake bottom from San Carlos to Rivas, passing north of Solentiname and south of Ometepe, was a financially costly and technically difficult project given the incessant depositing of muddy sediment in the lake water. The sediment was also very unstable and mobile which made it exceedingly complicated to keep this internal channel in the lake clear.

Even in those years excavating that channel was the toughest challenge in the canal construction—far greater than cutting through the earth. This problem obliged the US Corps of Engineers to study Cocibolca’s hydrography in detail, which led in 1898 to the development of the lake’s first bathyometric map, i.e. of the topography of the lake’s floor.

Today, just as then, Cocibolca is still very shallow with turbulently mobile lake floor sediments constantly displaced by the currents and the characteristic stormy waves churned up by wind.

In the absence of updated studies, the now obsolete 1972 bathymetric map of the National Promotion Institute (INFONAC), is still the only topographic reference for Cocibolca’s lake bed. It shows that approximately 60% of the lake’s bottom is less than 9 meters deep, 37% is between 9 and 15 meters deep and less than 3% is over 15 meters deep. Forty years later, with the copious contribution of sediment from the constant erosion of the surrounding basin, the depth is probably a great deal less.

While opening a channel in Cocibolca isn’t insurmountable given today’s technology, it would necessitate constant dredging to remove the sediments that would constantly fill it and be continually moved around by the currents.

Maintenance work on the channel will be indispensable; otherwise, natural forces will fill it in short order. Another challenge will be to resolve the problem of the moving and disposing of 1.3 billion tons of sandy mud from the initial excavation compounded by the daily arrival of 50 thousand new tons.

…an oil spill is its greatest risk

We’ve known since 1890 that the main difficulties in resolving the problem of excavating a channel across Cocibolca were first, the massive accumulation of sediment in the lake bottom due to the traditional watershed erosion and second, the constant unstable movement of this sediment due to strong wind currents on the shallow lake.

The combination of these two factors creates an even higher risk if shipping accidents occur. With only one fateful accident causing a “black tide,” all hope would disappear of ever using Cocibolca’s waters to supply potable water, irrigate the fertile soil or any other options.

Lake Cocibolca’s environment is extremely fragile if faced with pollution due to accidents involving hydrocarbons or other persistent toxins. Pollution of a body of fresh water surrounded by land inevitably constitutes the worst scene of environmental destruction. The technology that exists to mitigate petroleum spills has focused on bays and open marine waters where supertankers travel. If a pollution spill were to occur in Lake Cocibolca, no type of remediation would save the strict quality of water required for either drinking or irrigation. An oil spill, accidental or deliberate, will inexorably contaminate the waters with tragic consequences for our country.

Other risks, such as the invasion of new species of undesirable organisms into Lake Cocibolca or the salinization of its waters with the entrance of sea water, would be equally destructive.

The lake’s uncontrollable natural forces

We also have to consider the currents pushed by the wind in Lake Cocibolca, which are of great ecological importance. The wind is responsible for the turbulence that vertically mixes the column of water that pushes the water currents circulating from one side of the lake to the other.

The average speed of the winds observed on Lake Cocibolca is about 9 meters per second. Although we don’t know the hydrodynamics of the lake’s currents with the depth and detail necessary for the geometric design of the channel that would cross Cocibolca, we do know that the constant wind on the lake is the force that drives the movement known as Langmuir, which is capable of daily moving thousands of tons of already-existing mud and depositing it in areas adjacent to the canal and also rapidly filling any artificial depression in the bottom of the lake

This phenomenon, which constantly drags millions of tons of unstable sediment already present in other areas of the lake, has the capacity to continually block the channel they intend to excavate in the lake. These uncontrollable natural forces go beyond any technical, human and financial ability to keep the channel open for navigation. Maintaining the 90 kilometer long, 520 meter wide and 30 meter deep channel through the lake clear will be technically and financially more costly than the initial construction cost.

The lake’s characteristic turbulence caused by the intense wind, associated with the abundant mass of moving sediment, could sooner or later cause shipping accidents that would end in a toxic spill. The project designers should consider this uncontrollable hydrodynamic force sufficient cause to determine that digging a channel across Lake Cocibolca is technically unviable.

The risk of ships being driven aground on the sloping sides of the narrow channel by the force of the wind is highly probable given that it creates waves of more than 4 meters in the lake and big ships suffer from limited maneuverability.

Variables beyond human control

There are many canals in the world, but few are interoceanic. The dreamed-of interoceanic passage that led Captains Diego Machuca de Zuaco and Alonso Calero to find the mouth of our “Freshwater Lagoon” in 1539 has today become a proposal that could make possible rapid transit from one ocean to the other for the world’s largest present-day ships—those that can’t pass through the Suez Canal let alone the now-widened Panama Canal.

Our Grand Interoceanic Canal would be the widest and deepest in the world, designed to be used by the specialized maritime market of supertankers and huge commercial ships capable of moving up to 20,000 containers. Although these monstrous leviathans flaunt drafts of 25 meters, they are paradoxically fragile, vulnerable and highly susceptible to accidents in water as shallow as those of our Cocibolca.

We must also keep in mind that climate change poses variables beyond human control that impose limits on this project’s hydraulic design. Seismic activity associated with the geological fault lines in the area also puts the huge investment in this project at risk.

We can’t justresign ourselves

We can’t just resign ourselves to sacrificing our Great Lake Cocibolca. Therefore, the best route for a canal from the Caribbean Sea to the Pacific Ocean would be one excavated completely across terra firma rather than going through the waters of Lake Cocibolca, which we should not lose “even for all the gold in the world.”

Salvador Montenegro Guillén is a professor, ecologist and oceanographer, and was director of the Autonomous University of Nicaragua’s Aquatic Resources Research Center (CIRA) since founding it in 1980. This was his contribution to the first canal project forum organized by the Nicaraguan Academy of Sciences, in August 2013. Edited by envío.

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