(The figures for this paper are not yet included in this Internet version and will be scanned in at a later date).
INTRODUCTION
When developing water supply sources for cities, particularly those in geographic zones with extensive temporal and spatial variation in water source conditions, resource planners need to take into account the dual considerations of water source proximity and environmental health concerns in determining their ability to maintain acceptable quality and quantity of water service to residents at an acceptable long-run average cost.
In the most general of terms, the closer the water source and its watershed to the city when developed, the lower the capital cost associated with its transportation to the point of use, all things remaining equal. However, nearby watersheds are also most prone to environmental health and degradatory pressures related to their proximity to existing urban zones and availability as sites for urban expansion, natural resource exploitation such as the extraction of firewood or lumber, recreation, market gardening and other commercial land uses associated with the market for non-water goods and services (Leonard, 1987).
In light of these risks, it is common to find that many large metropolitan areas of the United States, geography permitting, have historically chosen to exploit more distant, upland and largely rural or wildland watersheds as their surface water sources, based on reliability and vulnerability criteria. New York City and the Catsgills, and San Francisco and the Tuolomne Valley are but two examples of the forward looking decisions made by cities in the last 75-100 years. Each selected surface sources which demonstrated adequate source yield to meet long-term future needs and the relatively protected catchment conditions necessary to guarantee sustained production at acceptable raw water quality levels and to keep down long-term treatment costs. Capital construction costs were higher than exploiting local sources such as river intakes fed by those same catchments further downstream closer to users, but the ability to control upstream activities has offset many times over the annual expenditures that would have been necessary to maintain a similar quality of service over time.
In many developing countries, cities that may have started out small 20 years ago but are now doubling every 10 years or so and rapidly passing the million inhabitant status heavily rely on several watersheds and water sources that are physically within the effective margins of the urban area. Often this is due to the general lack of available capital, sufficiently long-range water resources planning, political will and consensus, or technical capability. This lack of geographical separation and the presence of urban influence on land use within the watersheds gives rise to a range of environmental problems with clear economic impacts in the long-run:
A particularly clear illustration of this phenomena exists in Honduras with the case of Tegucigalpa and its Guacerique River watershed and Los Laureles reservoir. While the environmental problems facing this project have their specific local character, they represent well the multiplicity of combining factors and their political, social and economic causes that can be found in many developing country watersheds today. Guacerique typifies the types of environmental pressures and competing and conflicting resource demands experienced in many watersheds close to urban areas and which are used as drinking water supplies.
TEGUCIGALPA AND THE GUACERIQUE RIVER WATERSHED
The Guacerique River watershed is one of three principal sources of water for the roughly 850,000 residents of Tegucigalpa, the capital of Honduras, which is growing at an estimated rate of over 45,000 per year. In 1995 and 1996, Guacerique has been the focus of intense political debate and conflict, related to decisions by the prior administration of President Rafael Callejas (1989-1993) to develop a low-cost, high-density housing project of up to 10,000 homes for public sector workers on high ground immediately adjacent to and draining into the drinking water reservoir. Moreover, the watershed has been the site of other public and private sector developments over the years that are in direct conflict with its role as water supplier, including the siting of military bases, industries and training institutions, the siting of the major peripheral transport route around the city, the development of battery-production poultry plants, and the industrial-scale extraction, both illegal and legal, of firewood. Future projects already slated for the watershed include the new Tegucigalpa international airport, another major water supply dam and a further expansion of residential development.
The Guacerique River watershed is located in the southwest of Honduras, delimited geographically by the Yerba Buena mountains in the North, Tegucigalpa to the East, the La Concepción watershed to the south and the town of Lepaterique to the West (Figure 1). It has a total plan area of 196 km2 with a relative elevation of roughly 900m and a high point of around 2,000m above sea level. The landscape is very broken with a large amount of steep slopes and arroyos which are dry in the summer months and carry highly fluctuating and torrential stream flows in the winter months. The watershed receives an average rainfall of 957 mm with a peak in August-September and a low in February-March (Andino in Lee, 1995).
The Guacerique River watershed currently provides around 30% of the potable water consumed by the metropolitan area of Tegucigalpa and its companion city Comayaguela, a stone's throw across the Choluteca River (van der Horst, 1995a). This comprises around 141,000 m3 per day, and services mostly the lower elevation zones of the city, largely in Comayaguela, due to the high costs of pumping from the relatively low-lying water treatment plant. The Los Laureles reservoir was built in 1974 as a short-term project to meet Tegucigalpa's growing water needs. For investment analysis purposes, the project was expected to meet the city's needs for around 20 years. It fell short of this mark well before this date, precipitating frequent water shortages and the need for rationing in Tegucigalpa, stunting expansion of water service to the growing population, and accelerating the need to build the La Concepción dam and reservoir in an adjacent, and less developed, watershed. La Concepción, the largest of Tegucigalpa's water sources, came on line in 1993 and now supplies around 50% of the capital's users.
Agricultural and urban activities occupy around 20% of the land area of the Guacerique River watershed, with an estimated 75% of these lands supporting land-uses generally considered incompatible with its function as a drinking water source area. Urban land use has increased thirteenfold in less than 20 years. It is estimated that the Los Laureles reservoir, with a total design capacity of 106 m3 has been rapidly filling up with sediments, although no detailed bathymetric or balance studies have been performed. Average erosion rates from hillslopes have been estimated to be greater than 800 m3/km2/year (Andino in Lee, 1995). With a watershed area of 196 km2, this represents a loss of more than 200,000 m3/year or more than 2% of its volume annually. Other sources of erosion along river and stream channels, from construction sites, and from unpaved roads, lead some specialists to suggest that the loss of volume could be as high as 5% per year, particularly in wet years. This has contributed to the reservoir's failure to meet its design goals and accelerated the need to bring on line the La Concepción project. It is also directly responsible for the investment of over $9m in 1994/95 to install an inflatable rubber dam and compressor on the spillway to increase peak storage by approximately 3m m3 (Betancourt, 1995) and thus recover some of the storage volume lost to sediment accumulation.
RESOURCE CONFLICTS IN THE GUACERIQUE RIVER WATERSHED
The Guacerique River has been a source of potable water for the people of Tegucigalpa for many years, and was exploited as a municipal source in 1974 when construction work on the Los Laureles reservoir and aqueduct was completed. To try and safeguard the watershed and the water resources it provides to Tegucigalpa, the government declared the whole watershed as a Protected Forestry Zone in January 1973, publishing this declaration in the official gazette in April of that year (Betancourt, 1995). This status was never rescinded and remains on the statutes, but the necessary regulatory elements were never established to ensure compliance. With the continuing growth of the urban center of Tegucigalpa and Comayaguela out to the east, it was decided to more forcefully protect the area of the watershed by decree and so with the urging of the national water agency SANAA (Servicio Autonomo Nacional de Acueductos y Alcantarillados), the zone surrounding the reservoir, including areas now occupied by upscale housing and by the Ciudad Mateo project, the area of the Tegucigalpa ring-road and other developments were declared by the Tegucigalpa Metropolitan Authority a protected area with restricted development in March 1981. Having fought for this protection, SANAA Directors later campaigned to have the designation lifted, for motives that are not clear, and the zone opened up for development. This took place in December 1986 (El Heraldo Newspaper, 12/18/95), leading the way for the developments seen today on the margins of the reservoir, starting with the upscale homes on the southern edge of the reservoir known as Ciudad Nueva. In light of these loopholes and inconsistencies, during the last two decades, the Guacerique River watershed has continued to experience the piecemeal expansion of urban land-use and its myriad influences without effective controls or mitigatory measures. Several clear examples can be identified.
Residential Development: A major conflict in the Guacerique River watershed has been the 10,000 unit low-income housing project known as Ciudad Mateo. It was conceived of and started during the administration of President Rafael Callejas (National Party) and financed by the public workers retirement fund, the Instituto Nacional de Jubilaciones y Pensiones de los Empleados del Poder Ejecutivo (INJUPEMP). Left to the administration of President Carlos Reina (Liberal Party) to implement, Ciudad Mateo has perhaps become one of the leading controversies related to environmental management and official corruption during the Reina presidency.
Ciudad Mateo was officially conceived in February 1991, with the development of a draft planning document that was agreed to by the National Congress just over a year later (El Heraldo Newspaper, 12/18/95). The final approval was granted by Congress to go ahead and break ground on the project on July 1, 1993, 19 days before the passage in Congress of the new Environmental Law (GOH, 1993) which was supposed to prevent potentially environmentally damaging and costly projects from occurring in Honduras without a full environmental impact review and, as deemed necessary, the implementation of remedial measures. In the case of Ciudad Mateo, no such formal impact assessment was made although a preliminary environmental study was carried out in January 1993 (Myton, 1993) by the precursor to the new Environment Ministry (the Comisión Nacional del Ambiente, CONAMA). At that time, CONAMA did not have the statutory powers to halt the project although this was their recommendation based on the multiple negative impacts that were forecast. No remedial measures were implemented during construction that apparently had already begun in 1992 ahead of official approval.
Military Installations: Another example of land-use conflicts is the continued growth and expansion of military facilities along the Tegucigalpa-Lepaterique road, and which includes the major developments of the Honduran Military Academy, The Center for Military Logistic Support, the Honduran Military Industry complex, the Fourth Infantry Battalion, The Discua-Elvir Military Hospital and The National Police Academy (formerly military police) amongst others. The majority of these facilities were constructed with only basic sanitary sewer systems collecting wastewater and conducting it to adjacent water courses that lead into the reservoir. Many observers have noted that a previous chief of the Armed Forces and ex-President, General Lopéz Arrelano, who was instrumental in decisions to undertake development for military and civil projects along the paved road to Lepaterique, has sizeable land interests as well as his extensive family residential compound in the watershed.
Tegucigalpa Urban Ring-Road Project: The siting of the urban ring-road provides a clear example of how inter-sectoral interests and powers have clashed over resource management policies. Over the objections raised by the technical staff at the national water company SANAA (a semi-autonomous institution), the public works and transport ministry, SECOPT (Secretaría de Obras Públicas y Transporte), a powerful element of the national government, went ahead with their planned route and design for the part of the peripheral ring-road that connects the country's main highway to the north with the southern highway. The ring-road skirts the high-water margin of the reservoir from one side of the dam all the way around to the other, crossing the Guacerique river just upstream of its inflow point. SANAA watershed staff rejected the proposed design for a wide range of reasons:
A New International Airport: After a consideration of different proposals, the national government recently selected the Lake Pedregal site in the northern section of the Guacerique River watershed feeding Los Laureles for the construction of Tegucigalpa's new international airport. Construction is slated to begin next year once financing has been secured. The chosen site is close to one of the major tributaries (Quiebramontes River) of the reservoir and creates added potential for environmental contamination. The site also is upstream of the proposed site of the next major water infrastructure investment, a second dam (Quiebramontes) above Los Laureles, to take advantage of the more than 80% of annual average runoff that passes unused over the Los Laureles spillway. This dam will have an expected design capacity of 50m m3 (Betancourt, 1995). Recent efforts by the Environment Ministry to require an environmental impact assessment for each development project, governmental or private-sector, in compliance with the 1993 Environmental Law, could prevent some of the major excesses seen historically with construction projects like the ring-road. The airport project will need to obtain an environmental license prior to construction and this assessment review process, if forcefully implemented and backed by government leaders, could lead to better problem prevention and mitigation on this and other major construction projects.
THE COMPLEXITY OF COMPETING RESOURCE NEEDS: THE EXAMPLE OF CIUDAD MATEO
Ciudad Mateo is planned to comprise up to 6,400 low-cost houses, assembled from composite panels and asbestos roofing sheets for lower-level public employees, as well as roughly 4,000 mid-priced brick houses on the upper slopes in a zone known as Los Altos de las Topias. Although it occupies only around 0.5% of the Guacerique River watershed, its importance is much greater due to its critical location only four kilometers upstream from the Los Laureles reservoir (Betancourt, 1995).
President Reina has been under considerable pressure to shut down the project. However, one of the stated objectives of his government has been to expand the housing stock, particularly at the lower-income level, by 50,000 in his four-year term. The Ciudad Mateo project is therefore of vital interest in achieving this target and his Liberal party would suffer a political setback if this INJUPEMP-funded effort were halted. The Environment Ministry, has stated its opposition to the continuation of the Ciudad Mateo project citing the tremendous conflicts of interest in presents. It has been trying to apply the new Environmental Law to prevent completion of the project until remedial actions are implemented to comply with new guidelines for environmental protection. Two basic options have been presented to the government: either halt, dismantle and restore the site at a cost of more than La250m or roughly $30m (El Periódico Newspaper, 7/21/95); or continue with the project but implement mitigatory measures, including the installation of a treatment plant for wastewater and the construction of a large retaining wall to prevent sediments and urban waste washing off the steep streets and slopes on which the housing development is built. The cost for this option was estimated at around La150m in 1995 (roughly $18m). Either way, the investment required, coupled with the increased costs incurred related to the delays in the project and the legal maneuvering of the various parties concerned, will have more or less tripled the unit cost of the houses being constructed from around $6,000 to around $24,000 according to preliminary estimations by SANAA staff. Recent attempts to apply the Environmental Protection Act and force the project's contractors and funding agency to undertake the remedial measures has met with a barrage of legal documents as well as statements from ex-President Callejas to the effect that this law does not apply since it was adopted by Congress 19 days after permission was given to proceed with the Ciudad Mateo project and is not retroactive. If the measures are implemented, it is possible that the Honduran government and taxpayers may thus end up picking up the tab. However, according to Article 2 of the regulations that accompany the Environmental Law, this legislation does indeed seem to apply to whichever activity is potentially damaging or which actually contaminates or degrades the environment and natural resources (GOH, 1994).
The installation of a wastewater treatment plant is of particular concern to the Environment Ministry and to SANAA and is the principal cost component of the required mitigation plan. The current design for Ciudad Mateo allows only for sewage collection through a network of gravity sewer mains and laterals, already built. The pipes extend down along the surface alongside the reservoir's edge to a point downstream of the dam where the sewage will discharge out into the Guacerique River. This, in turn leads to ultimately into the Choluteca River that runs east though Tegucigalpa and down through the dry southern agricultural belt and into the Gulf of Fonseca, a major area of estuarine shrimp cultivation. This design alone indicates the sheer lack of environmental criteria and sensitivity in the drafting of the development plans. Planners have ignored the spillage and leakage risk factors associated with this routing, particularly in light of the notoriously poor construction standards achieved by many of Honduras' public-sector contractors (this has been born out by seepage tests along the sewer line which have not met acceptable standards). The design also flies in the face of planned environmental protection and clean-up efforts associated with the Choluteca River.
A factor clearly not considered by government officials and ignored by project planners is the magnetic effect that this highly concentrated residential development, without provision of shops or other commercial facilities, will have on encouraging satellite developments in the surrounding areas, particularly of servant and vendor classes. Functioning as a small city of lower- to middle-class income-earners, Ciudad Mateo is sure to attract a plethora of shanty town developments on the surrounding hillslopes around the development and along the access road from the soon to be completed ring-road, to house the cleaners, house maids, tortilla sellers and other vendors that will seek to make their living from the residents of the new development. In turn, these shanties with their lack of basic sanitation and water supply and their use of firewood as the main fuel source will accelerate and augment the contamination of the reservoir with fecal material and solid waste, and the degradation of the surrounding hillside vegetation as firewood extraction increases. If the pattern observed in Tegucigalpa is repeated, this additional informal population of the Ciudad Mateo project could grow close to the size of the planned development, around 50,000 extra people.
While the catalog of errors, abuses and conflicts that Ciudad Mateo represents is depressing to most observers, the picture is not all bleak. Ciudad Mateo has surfaced as somewhat of a national litmus test as to the commitment of government to better environmental management and regulation and to raise awareness amongst the public as to the need for more integrated and environmentally sustainable planning and development. On December 13, 1995, the Public Ministry (similar to the United States Attorney General's Office) issued an official denouncement of 20 government officials and individuals associated with the Ciudad Mateo project for damages caused against the state, the national economy, the Honduran environment, public services and the Honduran society resulting from its impacts and the alleged corruption it represents. Officials include the ex-Labor minister, the ex-chief of SANAA, the ex-mayor of Tegucigalpa and the ex-Director of the Public Workers Pension Fund INJUPEMP (El Heraldo Newspaper, 12/14/95). According to a report produced for the Public Ministry on the judicial aspects of the Ciudad Mateo project, based on legal grounds the project should never have begun since it violates the Constitution, Municipalities Law, Forestry Law, Sanitary Code, and State Contractor's Law as well as lesser decrees and regulations (Public Ministry, 1994). One of the more egregious acts against the public interest was the La3m purchase of the tract of land on which much of the project was built six months prior to Congressional approval. The land was then divided in two and half of it was sold to INJUPEMP for La36m. When exposed, this price collusion provoked howls of disgust in the local press. Ex-President Callejas replied that the deal's critics clearly did not understand the real estate business (El Heraldo Newspaper, 12/21/95).
SOME IMPACTS OF UNREGULATED DEVELOPMENT IN THE GUACERIQUE RIVER WATERSHED
Even without the expected negative effects of the Ciudad Mateo and Pedregal Airport projects, one of the clear outcomes of this tapestry of land-use developments has been to create a wide range of contamination sources of both a non-point and point nature. Obvious point pollution include clothes and vehicle washing in the river bed, sewage discharge from military installations, residential septic tank overflows, and overflow from slurry lagoons at chicken hatcheries (Quezada, 1986). On a non-point basis, SANAA officials have documented extensive fertilizer, pesticide and herbicide applications on small market gardens and subsistence farms distributed throughout the middle and upper portions of the watershed, as well as several located on the alluvium of the Guacerique River near to the reservoir (SANAA, 1995). In turn, the reservoir has been seen to suffer from occasional algal blooms and an excessive growth of water hyacinths that proliferate, die and then taint the drinking water with decaying organic material, color, taste and odor, each of which affects the cost of treating water leaving the reservoir.
The Guacerique River watershed already produces water at the highest unit cost per cubic meter compared to the other principal sources of La Tigra and La Concepción, in part due to the pumping costs to bring it up to pressure in the lower service zones which it cannot adequately feed by gravity, but mostly due to the cost of treating the water through its treatment plant. Due to the high turbidity levels and fecal coliform counts in the raw water, chemical inputs are high, particularly of aluminum sulphate, coagulation polymers, lime and chlorine, as are maintenance costs for sand filters.
According to a report produced by a Dutch Consulting Environmental Engineer (van der Horst, 1995b), the Ciudad Mateo project alone has caused the following environmental costs during the three year period from 1993 through 1995:
These figures do not include the costs of future options to deal with the impacts of Ciudad Mateo if the project goes ahead or else is canceled.
Van der Horst (1995a) also produced a series of forecasts of the kinds of contamination that could be expected in the Guacerique River watershed between 1990 and 2020 assuming that the Ciudad Mateo project be allowed to continue unchecked. Table 1 presents a summary of these findings:
Table 1 Potential impacts of Ciudad Mateo on the Guacerique River watershed (from van der Horst, 1995a)
| Without Ciudad Mateo | With Ciudad Mateo | ||||
| Impact | 1990 | 2010 | 2020 | 2010 | 2020 |
| Population | 10,776 | 25,286 | 39,930 | 196,576 | 334,148 |
| Erosion m3/d | 175 | 273 | 360 | 624 | 978 |
| Reservoir volume m3 | 8.4m | 8.3m | 7.1m | 7.0m | 4.0m |
| Reservoir yield (summer l/s) | 700 | 700 | 670 | 660 | 400 |
| Sewage discharge to river (l/s) | 14 | 12 | 19 | 136 | 250 |
INSTITUTIONAL ISSUES AND CONSTRAINTS TO BETTER WATERSHED MANAGEMENT
As indicated by current SANAA chief of watershed management operations, David Ordoñez (personal communication, 1996), with less than a $1.00 per month increase on each water bill, Tegucigalpa residents could generate the $400,000 annually estimated necessary to implement an effective and widespread watershed management and monitoring program to control the most negative of the current land-use and resource practices upstream of Los Laureles. However, this has proven politically infeasible. In a first-world perspective, an extra dollar is a drop in the bucket. In Honduras, the same dollar would double many customers' water bills. On average, water in Tegucigalpa is sold at less than $0.10 per m3. Many households are not metered and pay only a flat fee of less than $1.00 per month. Revenue generation is thus limited and water is sold at well below cost price with heavy subsidies from the central government.
This poor cost-recovery on the part of SANAA, coupled with a high consumer price index at around 25% annually and the fact that watershed management is a line-item that few customers directly sense or miss, has led to a general lack of commitment to watershed management on the part of decision-makers. In 1995, the watershed management budget was slashed by more than 50%, technical staff and laborers were dismissed, and an intent to cease operations completely was announced by the general management. Almost all current-account funding was cut and only the presence of sufficient unspent soft project money donated by international lenders has allowed the unit to continue ticking over until a major external donor can be found to pick up the tab for the watershed management program. Currently, technical staff thus spend most of their time preparing structural readjustment plans and writing proposals to international donors such as the European Community and Japan in an effort to rekindle the management activities effectively frozen in 1995.
The lack of institutional commitment by SANAA management to the watershed unit is somewhat understandable if looked at from a purely bureaucratic perspective. There are a multiplicity of laws and division of environmental protection responsibilities at a state level. On paper, the task of protecting the watershed currently falls on the shoulders of the national forestry agency, COHDEFOR (Corporación Hondureño de Desarrollo Forestal), the Public Health Ministry and the new Ministry of Environment. SANAA's responsibilities are limited to the water supply generation and distribution infrastructure and the management of the land area in its immediate vicinity. However, for the lack of action by the other actors in the various watersheds feeding Tegucigalpa, SANAA staff have taken on this role since the mid-1980's even though they have no statutory responsibility (although an agreement was signed with the forestry agency COHDEFOR in 1991). But austerity measures in the fiscal budget has required agencies, particularly the under-capitalized semi-autonomous bodies such as the water and energy companies, to cut budgets and thus the decision to expend the watershed management unit. However, even though responsibility for management officially lies in other hands, the reality of the situation is that if SANAA does not take the lead on this issue and develop a coordinated program for watershed management it will probably not get done. The other agencies neither have the staff, the financial resources or the will to carry out the necessary work.
CONCLUSIONS
The example of Tegucigalpa clearly brings into focus the biophysical implications of the failure to coordinate national and municipal policies in managing and protecting the watershed, and the legal and institutional impediments that have given rise to this situation, including the lack of clear zoning restrictions and an institutional commitment to watershed protection. The resource inefficiency and social costs of failing to integrate the planning and management of key resources including the land, soils, forests and water of the Guacerique River watershed are also clear. The examples of Ciudad Mateo and the peripheral ring-road in particular illustrate the lack of coordination between government departments that has led to subsequent public sector projects that have directly caused a range of avoidable environmental and fiscal externalities, including the loss of investments in hillslope reforestation projects, active storage loss through accelerated reservoir sedimentation and increased water treatment costs.
While the individual issues described are specific to Tegucigalpa, the general problems they represent are commonplace. The lack of coordination severely limits the ability of many developing countries to sustainably maintain their current levels and quality of drinking water service to their urban population centers. The same can be said for many rural watersheds in Honduras, and in Central America in general, where the colonization and exploitation of previously forested or uninhabited watersheds is becoming a growing concern (Lee, 1996). The question of sustainable integrated watershed management and how it can be accomplished in the context of such competing natural resource uses is a critical one and must be addressed more closely by researchers, technicians and politicians alike in the coming decades. As shown by the case of Tegucigalpa, this competition and the conflicts created threaten to undermine a key element of the resource base on which the urban population relies: its potable water supply.
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