Ing. Jaime Collado | Holistic recovery of bodies of water as essential resources of life
Thank you, good morning, everyone. I thank you for your presence today. I have allowed myself to prepare a Power Point presentation so that you can follow along.
I called it "Holistic recovery of bodies of water..." because several things are required to recover a body of water, not just one thing.
[Slide 2]
So, first of all, I am going to present to you the origin and the solution of contamination. At first, it might seem like a contradiction to presents the origin and at the same time the solution in a single part; let me tell you why I do this.
Water is a cycle, there is a hydrological cycle, and whoever has read for example Ecclesiastes 1:7 will see that the hydrological cycle is defined there; but whoever has read Isaiah 54, 55 knows that there is another cycle, a cycle of the word, a cycle that contains the hydrological cycle and defines it doubly; and says: "Just as water does not fall from the sky and returns by evaporation without having allowed the vegetation to grow, the mouth that comes out of my mouth does not return without doing what I want". There is a double cycle set: there is a hydrological cycle and there is a cycle of the word.
So I have focused on that in order to make double cycle. In first place: what is the origin of contamination, and then: what is the solution; and in the end I will make reference to a third cycle.
[Slide 3]
The origin of contamination is multifactorial. We cannot say that someone is strictly responsible in the double sense of guilt and agent to recover water.
There are geological and atmospheric aspects; it is a watershed management thing; if we do not take care of the soil, erosion comes, it drags sediment and changes the use of soil; the productive activities of both agriculture and industry; human settlements; when we have an inadequate disposal of solid waste or when the discharges of the cities do not receive an appropriate treatment; all of this together leads to the contamination of bodies of water.
[Slide 4]
And the solution is inter-institutional, it is also multi-sectoral; not only someone who manages water is required, be it a community, a department, a state, a region, a province or a whole country, it requires local authorities that are there directly where the people are.
There are the providers of water services (either a large city or the community water and sanitation service agencies); wastewater treatment is required; the collection and treatment of solid waste is necessary in an appropriate manner; it is necessary to reduce the use of hormones and micro plastics.
In the morning, they told us that here in Panama, they have already sanctioned the practice of having plastic bags in the supermarket. I'm not talking about the pet or plastic bags, because that's something very obvious and it's something we can do; I'm talking about hormones and micro plastics, because usually we do not realize that we use them.
Maybe you can say: "I do not use micro plastics"; all of us here today, use a lot of micro plastics, from shaving cream, shampoo, the gel that we put on our heads or lipstick, mascara, or makeup, all those things have micro plastics; we do not see them but fish do, they eat them and they cause genetic damage and there is malformation in fish.
That part of micro plastics ..., and of course the hormones, hormones, there is not a single procedure to remove them from wastewater. As the hormones come, the body cannot metabolize them, and the wastewater treatment plants cannot either; just as a hormone enters the body, it goes out and so will all the aquatic life on this planet. That's something we have to do all over the world: control the use of hormones and micro plastics; and of course to achieve a consensus, which I have stressed because it is very important and it is linked to the third cycle that we will see later.
[Slide 5]
For the holistic vision, an entity that has a mandate and authority is required. And by authority I do not mean, shall we say, an administrative authority; I mean someone who has respectability, who has credibility, who has recognition. Authority is ethical or it isn’t; I refer to that authority.
Of course, a public policy is required. We must organize society to environmentally recover a body of water. Some money is required, a budgetary program is required, some hydraulic infrastructure is required and necessary human resources are also required to do so.
[Slide 6]
In addition, legal, regulatory, economic, financial, environmental, planning, inter-institutional coordination, housing, solid waste collection, capacity development and adequate social participation instruments are required.
Given the limited time we have, I cannot go into each of these issues, I just want to put in your mind that it is not easy, hence the importance of consensus.
[Slides 7-8-9]
Now, to try to locate what we are talking about, I am going to tell you about the case of a body of water that originates in the dispute over water.
500 years ago, Mexico City was a lake (here is Mexico City and all that was a lake). Since we have so many people living there and how they are inside an endorheic basin, that is, it is a closed basin, the amount of water that occurs there naturally is insufficient for the number of people who live there.
A nineteenth-century thought said that "well, if there is not enough water we can take it from other sides and we bring it here". All these points that are here are storage dams; all those that are here, these red dots, are storage dams. This is a huge aqueduct, which leaves part of the water in the state of Mexico and the rest to Mexico City (it used to be called Federal District, now it is called Mexico City).
The thinking of the 21st century would qualify that as ecocide, but that began a long time ago. So you can see how absurd this is of the Cutzamala System, water has to be raised in the order of 1000 meters (one kilometer); then there is a dam Colorines, we are going to talk about this Valle de Bravo dam in particular.
These are pumping plants, then there is a tunnel here, there is an oscillation tower to avoid water hammer; and then a regulation tank, another regulation tank, another tunnel, and finally it reaches the metropolitan area of Mexico City.
Of course, it is necessary to build a third line (where there are already two lines); precisely because what happens if one of those bombs stops working? Mexico City runs out of water.
Now, Mexico City is built on the bottom of a lake, most of its inhabitants are unaware of it. What are the conditions that are required to have a lake? There are two: firstly that they have a depression, a concavity; and second, that the vertical permeability is much smaller than the horizontal permeability, in such a way that the water does not infiltrate and stay there.
The question is: Are these conditions currently being met in Mexico City or not? The answer is: yes they continue to be given. Then, if we do not drain every day...; just as every day we bring water to Mexico City, every day we have to drain the water from Mexico City, to prevent the water from recovering the space that corresponds to it, which is a lake; well, that's how it was.
[Slide 10]
This origin of water transfer is precisely that: Mexico City sits in a basin that is closed. It took 400 years to drain, there were 6 lakes; and in the last 100 years, water has been and will have to be pumped into the neighboring basin of the Pánuco River. Then we altered three basins: we altered the basin from where we took the water, we altered the basin where we are rising and we altered the basin where we sent the water, because to make matters worse we do not treat that water; and well, the amount of water it uses is superior to the natural renewal that exists in that area.
[Slide 11]
The consequences of this transfer is that the city sinks from 6 centimeters to more than 30 centimeters per year; it is sinking constantly, every year it sinks; and of course, the sinking is not even, there are differential subsidence: sometimes it sinks more on one side than on the other, and what happens? Well, when an earthquake comes as we usually have, this becomes unbalanced and constructions fall.
The affectations to the supply network due to subsidence of the subsoil, together with the age of the pipes, means that 38% of the water that is distributed leaks through the network; that is to say, the sinking not only affects constructions, it also affects the network of pipes, because they are down there and if it collapses, it breaks them.
[Slide 12]
This is a graph of the subsidence accumulated from 1862 to 2005; and here they come, it's in meters. So this is where the airport in Mexico City is; in blue is more or less the trace of how the 6 lakes were, which were united in the summer season. This is the central part of Mexico City.
[Slide 13]
You see how this part is here, because another part of the major damage we had in the past seismic September 19, this was the lake as it was originally 500 years ago. Here, this series of red spots are where the buildings had the most damage, because it is precisely the transition zone between the lake and the mainland and that is where the soil is weakest; but I insist, the people who live there (I no longer live there) do not know that they live in the bottom of a lake; It has been quite difficult to convince them that this is so, because they do not see water, they think it is not true, but they live in the bottom of a lake. Of course, it is humanly almost impossible to reverse this, it would take hundreds of years to withdraw the population there.
Hernán Cortés arrived in 1521; in 1533 - only 12 years after arriving - the viceroy sent a letter to the king of Spain telling him that the city of Mexico had to be taken out of there, because it flooded every year. To Hernán Cortés, his commanders told him: "Do not put the city here! They do not fit! Take them out!" And he said: "No. We will put it here." There, he founded the city, he left Mexico and left us the problem.
[Slide 14-15]
Let's go back to the lake of Valle de Bravo. Valle de Bravo is in the middle of the problem. Yes, because they come from here and no longer watch the water go by but they also leave the problem. Since the Cutzamala System was inaugurated, the population of Mexico City and its conurbation has grown from 14 to more than 20 million inhabitants; the urbanized surface has increased 3.6 times; and the installed capacity (that is, what is sent, the transfer) has increased from 4 to 19 cubic meters per second. It's a world of water!
[Slide 16]
Now, what are the indicators of environmental deterioration in that lake in particular? First, deforestation: due to illegal logging, the use of firewood as a fuel, the incidence of forest pests, fires and legal exploitation (not illegal, but legal) the loss of more than 10,000 hectares of forest is recorded.
[Slide 17]
The change in land use and inadequate soil management has increased significantly due to agricultural and livestock exploitation; both agricultural and livestock practices are extensive and inadequate, and non-conservationist and low-yielding techniques are used; Temporary agriculture and irrigation by gravity are practiced, both with low profitability; and the cattle go free, stepping on and eating forest shoots (that is, you arrive, you do a reforestation, and the cattle arrive and undo it).
[Slide 18]
Erosion. 85% of the soils of the basin show some affectation; due to the intense erosion processes, there is a significant accumulation of silts in the lake, ranging from 1 centimeters per year to 1.2 million (sorry this is an error, it’s cubic hectometres per year): from 1 to 1.2 cubic hectometres per year; that is, millions of cubic meters per water, that is the accumulation of silts in the lake.
[Slide 19]
The reduction of the surface and depth of the water. There is a decrease of 40 square kilometers of the lagoon surface and drops of up to 2.6 meters are recorded. The main use of that lake is tourism, there are sailboats, there is fishing, there are a number of things; when the depth of the lake drops 2.6 meters, one cannot even use the docks, there is a significant effect on the economy of the place.
[Slide 20]
The organic load in the water. The discharges of untreated wastewater, from fifteen sites (because there are a number of villages around the lake), approximately 215 liters per second, and diffuse pollution throughout the lake shore, provide a large amount of organic load and nutrients to the lake; that what causes is that the algae grows, the bacteria grow, a series of microorganisms grow that practically eutrophize the water, it is as if they rot the water of the lake.
[Slide 21-22]
The contamination of soil and water. Because 33% of garbage is not collected, because 70% of wastewater from urban and rural areas is not treated (there are 120,000 inhabitants in that basin); and to the discharge of agricultural drains (400 to 800 liters per second) the lake, some springs and wells, as well as large areas of the soil, present high levels of contamination.
[Slide 23]
The internal load. The constant and increasing accumulation of contaminated sediments in the bottom of the lake significantly exceeds its capacity for natural restoration.
[Slide 24]
Threats to living species. Four aquatic species and 32 terrestrial plants are at risk of extinction.
[Slide 25]
Reduction of fishing production. Due to the use of inappropriate fishing methods, the introduction of exotic species (such as trout, carp, mojarra), overexploitation of fisheries and habitat alterations (such as turbidity, salinity, lily), fishing production has decreased by fifty percent; then it not only affects tourism, but also affects fishing.
[Slide 26]
The deterioration of water quality in Valle de Bravo. Derived from pollution, water presents high turbidity, scaling, high concentrations of nutrients in specific areas and abatement of the dissolved oxygen level in some specific areas. Under these conditions the lake is classified as a body of eutrophized water, that is, it has a greenish color, grows algae, has blue-green bacteria, is truly a disaster and even has an odor that is not appropriate for tourism.
[Slide 27]
In addition, there is a low environmental culture. The lack of a shared vision regarding the problems of the basin, the lack of continuity of the programs and commitments, the existence of a social network of fragmented participation and communication among the communities, and the lack of an institutional agreement, are factors that they allow adopting a long-term plan, with shared human, financial and material goals and resources.
[Slide 28]
There is also a low awareness. The majority of the population does not have appropriate information on environmental problems; and consequently, they have little awareness of the deterioration and overexploitation of water, soil and forest in the basin.
[Slide 29]
And if all this were not enough, there is a lack of alternative sources of work. Due to the conditions of 60% extreme poverty of the rural population of the basin, and the lack of jobs, the exploitation of natural resources is enhanced; that is, people do not have a job, the lake no longer allows them to live, and then they go to the forest, cut a tree, make firewood and sell it, and that increases the problem.
[Slide 30]
Now, water pressure. The increasing concentration of population in urban areas and their consumption practices, generate an increasing pressure on water and alters the ecological balance.
[Slide 31-32]
So, what is the solution? There are two visions. One of them says that there is a technological solution. Which is? Well, we must take preventive and corrective measures. If the lake is eutrophized (they say), the solution is to oxygenate the hypolimnion; this is the part where the greatest concentration of pollutants are; you oxygenate it and then remove it, and then the amount of algae, bacteria decreases.
So, they say you have to oxygenate the hypolimnion using, for example, a Speece cone (it is not commercial, but for example that), to break the cycle of the internal charge of the nutrients of the anoxic sediments and thus reduce the eutrophication and the cyanobacterial outbreaks.
Biomanipulation in deep water to combine with other methods and reduce algae taking advantage of the zooplankton food chain or limited use of herbicides to destroy algae in emergency situations.
[Slide 33]
A Speece cone is something like this. Air is injected here, then it goes down and arrives here. And then as the air tends to rise it moves the water; it is (as air weighs less than water) ... it is cheaper to move air than to move water. Before, what was done was that water was injected down, but that is more expensive; now what is done is that air is injected, and air alone goes up, and that makes a convection in the lake, and causes it to oxygenate and causes the lake to be cured, so to speak; but, of course, this requires a pump and therefore requires a line of electrical energy, it is not simple.
[Slide 34-35]
However, I believe that there is a fundamental solution, it is a consensus. Notwithstanding the preventive measures to recover water quality in the Bravo dam there and the environmental quality of its catchment basin, the most important ingredient is the consensus: If we do not convince the people who live at the top, that when you remove a tree or when you remove the vegetative cover a sediment streak will come that affects the one below, we will never be able to agree. If we do not convince a person to discharge garbage into the water ... because there is often garbage collection, but when it rains, they say, well, they take out the garbage and throw it into the stream to take it away; with everything and that they know that the next day there will be garbage collection, they throw it to the stream! You have to convince them of that, you have to go and you have to convince them, you have to work that part, and you also have to watch.
[Slide 36]
The lake of the Valle de Bravo dam has been decontaminated with the attribution of multiple actors: Basin consensus has been reached, people have been seated, convinced, financial resources have been sought, programs have been made, the lake has been totally decontaminated ...; and yet, it becomes contaminated again.
It's very simple, the authorities change, the actors change and forget what happened; the one who arrives wants to erase everything the previous municipal president did and wants to invent everything again. Do not!
Then, the benefits of environmental recovery must be reaped every day; as the companion says: you have to say hello every day, the lake has to be watched every day! And if someone throws garbage, you have to go and explain that you do not do that; and if someone wants to do a wastewater discharge, you also have to go and convince them not to do that. Then, when the actors change because the quality of the lake deteriorates again, that is a problem.
[Slide 37]
So, this is very important, RIGHTS.
Once a right is fulfilled (in this case environmental health) it becomes a struggle to conserve it. That is to say, we say: "we have the human right to water". Once we get that right, now we have to fight to keep it, and that someone does not come and snatch it from us. Then, once we decontaminate a body of water, we have to watch! So that it does not become contaminated again; if not, it becomes contaminated again. And that lake has been decontaminated and polluted like that cycle I was talking about.
It is another cycle: it is contaminated and decontaminated, contaminated and decontaminated, and decontaminated again; and the lakes do not protect themselves, it is necessary for someone to protect them.
Who will protect them? No, well you, you, you ... and me. We all have to protect it! The lake is not protected alone, someone has to do it, we are the ones who have to do it; therefore, the cost of environmental law is eternal vigilance.
It seems like a strong sentence. That is, we have a right to environmental health, yes. And what is the cost? We have to monitor it every day, if not, we lose that right. It's like freedom, the cost of freedom is daily vigilance, every day we have to do it.
Thank you very much.
SUMMARY
The contamination of the bodies of water is multifactorial and is related to geological aspects, with the productive activities and the change of land use, with the situation in the rivers, drains and channels and with the use of water. It is a situation that involves multiple decision makers and institutional instances that implies adequate coordination to articulate efforts and ensure that the deterioration of the environment is stopped and reversed.
The actions for the environmental recovery of bodies of water clearly demand the need for a multisectoral vision that integrates institutional, legal, regulatory, economic, financial, environmental, planning, coordination, housing, solid waste collection, and development aspects. of capacities and of the adequate social participation that allows to reach consensuses.
To this end, an entity with the mandate and authority is necessary to achieve the correct application of public policies and budget programs are required, as well as to obtain the necessary hydraulic infrastructure and human resources.
INTRODUCTION
With the increase of socioeconomic activities in the basins, the water quality of the storage dams deteriorates significantly. As a result of deforestation, the expansion of the agricultural frontier without adequate soil and water conservation practices, and the growth of the urban and rural population that does not have adequate drinking water services, sanitary sewage, wastewater treatment nor the sanitary disposal of solid waste, bodies of water, particularly lakes, tend to exhibit eutrophication.
Under this situation, it is more difficult - in terms of the unit processes of purification for human consumption and costly in economic terms - to comply with the technical health standards that govern the quality of the drinking water supplied to the population. This document shows that the recovery of water bodies includes and exceeds purely environmental actions: it is also necessary to recover the social fabric, which usually requires holistic vision and actions. As an example, Lake Valle de Bravo, one of the components of the Cutzamala System, is used.