Water Resources Foresight Program in Guanajuato
Confronted with an uncertain future for the Guanajuato’s water resources, the State Water Commission designed a planning approach based on two ideas:
- To view the water resources planning and management problems as part of a much broader system, made up of technical, social, economic, political, environmental and institutional “realities”, that had all to be taken into account concurrently in order to understand the true roots of problems.
- To take a systemic, long view (20 to 30 years) of water resources, because only by looking at the distant future it will be possible to evaluate what policy will make the resources sustainable.
To implement the necessary planning approach, the State Water Commission needed a method that combined: (a) an integrated water resources management framework as the platform for the implementation of its planning approach and (b) system thinking as the paradigm for the effort to be undertaken.
Searching into the water resources literature for an approach that was close to what the State Water Commission needed brought many articles on integrated water resources management, or IWRM as it is commonly known, but none matched what Guanajuato required.
The same was true when the search was directed to long term analysis. A plethora of articles about applications of the system thinking for long term analysis can be found, but not directly related to water resources.
One of the very few articles that address both IWRM and system thinking emphasizes the need to employ the Systems Approach to: “integrate planning and management of water resources, since this [the systems approach] provides a very efficient solution to complex water resources problems.”
The current literature on IWRM focuses primarily on descriptions of the “real world” needs for integration. For example, an article on IWRM from the Southern Africa region defines IWRM as: (1) the hydrological cycle, that is, the downstream and upstream uses of water, the surface and ground water supply and, most important, rainfall, (2) the full range of sectoral interest, where all relevant objectives and constraint of society are considered and (3) the future needs as legitimate claims to the water resources. However, the article does not outline a mechanism to accomplish the integration for planning or management purposes. System thinking is a relatively new coined concept and is being used for business applications while the “systems approach” is a time tested control and aerospace engineering “way of thinking and solving” problems. Both systems thinking and the systems approach are based on Dynamic and Control Theory and the feedback principle.
System thinking methods tend to be more qualitative while the Systems Approach tends to be more quantitative. Systems Dynamic Simulation is a most useful tool that the engineer has available when it is required to understand the time related behavior of a complex system, such as the state of Guanajuato.
Using ProEstado – Guanajuato as Base Model for MAUA
The model ProEstado–Guanajuato had already been deployed by the state of Guanajuato planning authority when the State Water Commission initiated the process of looking for planning tools that would support the planning approach discussed above. The examination of ProEstado–Guanajuato by these authorities indicated that the model had the structure to represent water demands of people for life support, food production, and industrial development. ProEstado-Guanajuato even included an aggregate water supply and demand model that had been employed to pinpoint the precarious condition of this sector in the state. The capabilities of ProEstado-Guanajuato soon convinced the State Water Commission that this model was a good starting point for designing and building MAUA (in Spanish, Modelo de Abasto y Uso del Agua, that translates into Water Supply and Use Model). However, a drastic adaptation of ProEstado-MAUA was required to convert it from an aggregate state level model to a watershed specific model. The development and construction of ProEstado–MAUA started in June of 1998. It was concluded in January of the following year.
The systems dynamics approach of ProEstado-MAUA breaks the single-water use analysis paradigm and focuses on a more important subject, the final use and control of the resource, regardless of who uses it. Once directed towards this central objective, ProEstado-MAUA pinpoints flaws in policies that are being designed to “solve the problems” and that, contrary to their intended purpose, may even reinforce the existence of the problem.
ProEstado-MAUA is also useful as a tool for helping to reflect on ways to avoid future problems instead of, as it is being typically done, reacting to problems only after they have already occurred. In the systems dynamics paradigm this is possible, since the methodology itself enables us to find the causal loops through which we can ascertain the future levels of performance of the state water resources systems.
One of the functions of ProEstado-MAUA is to increase the overall knowledge of a situation, since knowing about its possible futures tells us what we should be doing today. In short, ProEstado-MAUA provides a solid platform for water resources planning since:
- It has the capability of integrating in a single model the visions of the various water uses that go beyond the traditional single-water use approach.
- It provides the means to visualize what happens when we simulate the implementation of a policy. This capability, when shared with others, serves the purpose of improving our communications.
- It handles physical as well as social variables in the same model, helping us to determine the impacts on both sides that result from the implementation of policies over an extended period of time.
MODEL COMPUTER IMPLEMENTATION
For the computer implementation of ProEstado-MAUA the dynamic simulation package Stella Research ®, Version 5.0, for Windows, was employed.
Stella has an input interface and editor that enables the user to build models through the use of “icons” that represent state variables, connectors or auxiliary variables. These last ones can be constants or function of various state variables.
HOW TO USE THE MODEL
ProEstado-MAUA was designed and built to examine long-term, complex water and water related issues such as: What is the outlook of Guanajuato’s agriculture over the next 20 years?
To examine this question, a set of policy variables from ProEstado- MAUA can be selected to formulate the issue in terms of the model structure. For example, if we are interested in decreasing water demand for agriculture, and, at the same time, decrease demand of drinking water, Table 1, below, tells us which policy variables we can select.
We can: (1) reduce Cultivated area, or, (2) increase the level of Irrigation technology, or, (3) apply a Change of crop. We can also apply these three policies, all at the same time.
(1) implement a program to foster the Use of water saving devices, or, (2) reducing the Number of drinking water wells in use.
Table 1. Submodels and their policy variables
|Agricultural production||-Cultivated area
-Change of crop
|Socioeconomic||-Use of water savings devices
-Number of drinking water wells
It should be clear to the reader that although one can reach the objective of “decreasing water demand for agriculture” with any of the policies shown in Table 1, it is not the same thing to reduce Cultivate area, as to Increase Irrigation Technology, because these two policy variables will have different impacts on the watershed.
In the case of reducing the planted area, this measure will produce unemployment among agriculture workers. If, on the other hand we increase the level of irrigation technology, we do not fire workers to the contrary, one can think that more people will be needed to handle the improved technology.