Contents Characterization

Results

Results of the field investigation are synthesized as coming from four zones of the basin: I Tropical Dry, II Tropical Wet, III Coastal Wet and IV Montane Wet (Map 9). Based on these results, conclusions and recommendations are then made to the IS/DWC, to PROCUENCA-SAN JUAN, and to the local and national governments of Costa Rica and Nicaragua.

I Tropical Dry (Lake Nicaragua and its tributaries))

In the SJRB, this entire zone lies within Nicaragua. With annual precipitation ranging from 750 mm to 2500 mm, and temperatures between 23ºC and 28ºC (the higher temperatures occur north of the lake), this zone tends to have tropical grass savannas with ranching and agriculture (e.g.: rice, corn, wheat, sorghum and beans) as the main economic activities. There is a low to moderate threat from hurricanes to the municipalities located along the upper half of Lake Nicaragua, with a moderately high threat to its northwest (Map 10). The entire zone has a moderate to very severe threat from drought, and is exposed to short but very heavy rainstorms. Water sources, which can be drilled or hand-dug wells, rivers, streams, ponds, and cisterns in the rural areas, and piped water in the urban areas, seldom go dry. However, they can be affected by heavy storms and subsequent silting in of ponds and wells.

Most of the population in this zone lives to the west and southwest of the lake, where poverty levels are not as severe as they are north of the lake (Map 11). The road network in the more populated areas is generally good, but in the poorer zones near the lake, roads are scarce and in generally bad condition. Consequently, transportation is usually by boats that ply the lake between population centers.

The zone has been populated long enough so that the local communities have figured out how to take care of themselves during extreme meteorological events. As can be expected, however, problems occur in the poorer communities that are forced to live in the more precarious situations within the flood plains of rivers and streams, and in low-lying areas around Lake Nicaragua.

In response to the request from the IS/DWC for examples of best practices of households and communities used to cope with climate variability, the following should be mentioned. It is significant that NGOs play a major part in many of the practices at this level.

  • Water quality is being protected by reforestation of the main watersheds and riparian areas.
  • Schools and other institutions adopt a river or stream to keep their water clean and their banks vegetated.
  • Environmental education programs are available in several locations to train local populations to protect water sources; ground water restoration and management is emphasized in some of these.
  • In communities where ENACAL is not active, the office of the mayor has staff that work with civil defense organizations to protect water sources—again usually by reforestation and forest protection.
  • If during a storm floodwater rises significantly and threatens to contaminate the water source, be it hand dug well, small pond or cistern, members of the household or the community channel the excess water away.
  • If a water source for a household or community is threatened by extended drought, water is shared between neighbors.
  • When water sources of larger or more fortunate ranchers go dry in the summer, they move their livestock to a second property in the mountains where there is sufficient water and forage.
  • Most of the larger industries have their own source of water which they maintain, also protecting the forest cover around the spring, creek or pond.
  • Care is generally taken to keep water wells above sources of contamination such as latrines and corrals.
  • All of this is easier to do if the community or municipality has a water committee; relatively few municipalities have them, however.
  • Municipal governments that find themselves in charge of the water supply are always looking for new sources. Generally, they look to exploit new ground water aquifers. If water becomes scarce during extended droughts, rationing is mandated.
  • To prevent future water scarcity, one municipal government is attempting to increase water capture by tearing out older dams and allowing the river to flow freely over groundwater recharge areas.
  • The same municipality has an emergency plan that includes coordination with ENACAL in flood or drought emergencies.
  • Municipal governments coordinate with one another and with national agencies concerned with water supply, emergency response, civil defense, and health.
  • During lengthily droughts, water supply agencies store and release water according to schedules and, during nighttime, they may close down the system to conserve water.
  • All of the national agencies and many of the local water supply and health service institutions have emergency plans.
  • Health workers are aware of the specific diseases that can contaminate the water supply and become especially bad as water volume dwindles. Plans and the supplies needed to chlorinate water sources are in place.
  • Water supply institutions have plans, but not always the resources, to extend piped water services to all neighborhoods.
  • In some localities, there are emergency wells that can be brought on line during extended droughts.
II Tropical Wet (San Juan River and its tributaries))

This zone is found almost equally distributed between Costa Rica and Nicaragua in the SJRB (Map 9). Where human intervention is minimal, this zone, with an annual precipitation rate ranging from 2,000 mm to 4,000 mm, is generally covered with humid to very humid tropical forest—especially on the Nicaraguan side of the border where communication by land is difficult and population density falls off rapidly away from the lake. The Costa Rican side has a history of agricultural intervention (plantations of sugar cane, rice, citrus, heart of palm, palm oil, banana and other tree crops), a more complete road network and a higher population density scattered in small communities. The San Juan River becomes a major transportation route.

Poverty levels are high to severe (Map 11). Services are minimal and potable water is scarce, especially just south of the lake along the border. Even the official water distribution systems are not usable because the aquifer has been contaminated by pesticides. It is from this zone that many people from the Nicaraguan side of the border find their way into Costa Rica. Except for the far north of this zone, flood threat is generally quite high in both countries, and reaches moderate levels along the major rivers and just south of the lake (Map 12, Map 13). Hurricane threat is very low to moderate (Map 10). During dry periods, the drought threat can be severe.

Rivers and streams, as well as springs and hand-dug wells, become the drinking water source in rural areas to the south and downriver from Lake Nicaragua.5Community and municipal water systems often depend on storage tanks and gravity feed. Except in the drier parts of this zone, coping with extreme climate variability is less entrenched; here, many of the inhabitants north of the river live at a subsistence level and, since their work is to open the agriculture frontier, many are recent arrivals. Because of this, coping practices become more the responsibility of municipal authorities and the health sector than they are to individual households. On the Nicaraguan side, these institutions are primarily ENACAL, and SILAIS. On the Costa Rican side, they are AA, and EBAIS.

  • Staff members of all of these institutions receive training in emergency response.
  • During flood emergencies that may affect water sources in the Nicaraguan portion, SILAIS coordinates the work of the mayors, the environment ministry, ENACAL and any other government or non-governmental organization.
  • SILAIS has a plan for emergency evacuation and shelter for areas where flooding is a problem.
  • EBAIS has local emergency plans for maintenance of water supplies to clinics and to affected citizens.
  • EBAIS gives talks to its patients on how to protect water sources.
  • SILAIS has equipment to make chlorine and an emergency environmental health team to treat water in case flooding contaminates the water sources.
  • Communities in Costa Rica generally all have emergency committees and plans.
  • Plans include both preventive measures and activities of coordination that are initiated and coordinated by the National and Local Emergency Commissions.
  • Members of these are representatives from the different state agencies, local authorities, and private organizations with responsibilities in the community.
  • If scarcity of water affects sterilization of medical and non-medical equipment, water from the emergency storage of ENACAL is used.
  • Where ENACAL does not have offices, it is the mayor’s responsibility to supply water to the population.
  • Health centers have post-emergency services that include chlorination of water systems, fumigation of disease vectors, and counseling to help with post disaster depression.
  • Some municipalities find it necessary to have a municipal well, since post emergency action is prioritized and they are often at the end of the line.
  • When irrigation is necessary, the water is taken from the rivers rather than wells.
  • Some municipalities have an emergency plan for both drought and flooding.
  • For those sites closer to the larger cities, water may be trucked in from their sources during times of extreme drought.
  • If flooding contaminates the water source, ENACAL has cleaning teams and a department to monitor contamination levels and make the necessary adjustments in treatment.
  • In those places where communities normally get their water from small streams and these streams are contaminated, EBAIS brings them water and uses that opportunity to teach about not throwing garbage, dead animals, etc. into the water.
  • In places where the water source is a spring, AA fences it in and plants the surrounding area with trees.
  • When flooding affects the water source, a citizen network diverts or pumps excess water away from the source.
  • Well water is either filtered or disinfected with chlorine.
  • Wells are dug far from any source of contamination.
  • Deforestation is prohibited in areas where there is a water source.
  • SILAIS gives educational talks on saving and storing potable water, and chlorinating wells.
  • During a drought, SILAIS provides water to health centers and hospitals.
  • In the more arid areas, water is collected in barrels and cisterns as early as possible during the rainy season.
  • Most industries in these municipalities have their own source of water and a large capacity for storage.
  • The non-governmental organizations active in these municipalities work with soil conservation practices and reforestation of the deforested watersheds.
III Coastal Wet (Indio-Maiz-Tortuguero coastal zone)

For the most part, this zone is made up of swamps and agricultural lands in Costa Rica and low-lying forests and swamps in Nicaragua in a half-moon shaped strip along the Caribbean coast. Its northwestern edge has become an agriculture frontier as landless peasants search for a place to farm. Its southwestern edge has already been utilized for banana plantations and ranching. By far the largest part of this coastal zone, however, is made up of a bi-national complex of protected areas (biological reserves and corridors, wildlife refuges, forest reserves and national parks) called “Sí-a-Paz.” At something close to 4,000 Km², these protected areas represent a significant portion of the SJRB (Map 9).

There are five or six small villages along the coast that date from the 1850’s, and a dozen or so centers between the mountains and the lowlands in Costa Rica. These developed even earlier as large banana and cocoa plantations, which later were the object of both directed and undirected colonization schemes. Apart from these centers, some of which are rapidly growing, the population tends to be lightly scattered along the river, in logging camps and cattle ranches.

Poverty levels in the occupied areas are high. Potable water service does not seem to be able to match population growth, since efforts to supply and adequately administer potable water in many of the population centers are falling behind demand.

Population centers located on the edge of the mountains receive muddy water. This is because the high-energy stream carries more sediment, as well as road construction and landslide materials. Flood threat is very high because of the lack of elevation, storm surges, high water tables, and very high annual rainfall of between 3,000 mm to 4,000 mm inland and up to 6,000 mm along the coast. Temperatures are high. Hurricane threat is moderate to very high; the threat of drought is low. Except for the larger population centers that receive water from AA, the remaining cantons have water associations or committees that AA regularly advises.

  • Hospitals located inland can treat many patients at a time but most have no organized plan to deal with water problems caused by flooding. Those that do have a plan also coordinate with the National Commission on Emergencies, AA and the municipalities.
  • AA is responsible for protection of potable water sources; it coordinates with MINAE in the protection of forests surrounding these sources.
  • Emergency commissions are generally made up of representatives from the fire department, Red Cross, Rural Guard, the local hospital and the municipality.
  • Environmental NGOs support work of reforestation and forest conservation to protect water sources.
  • Communities have lined, raised, and covered their water sources to protect them from contamination.
  • NGOs that manage land calculate the “environmental value” of letting forests protect the water resource and are paid this amount which then allows them to give land and water management advice to other landowners in the area.
IV Montane Wet (Cordillera headwaters)

This zone stretches along the highlands of Costa Rica from the Cordillera de Guanacaste in the west, through the Cordillera de Tilaran and then to the Cordillera Central before dropping off to the Caribbean Coast. A series of volcanoes, four of which are over 2000 meters and one of which peaks at almost 3500 meters, marks the southern border of the SJRB. It is a zone of high precipitation (between 3,000 mm and 5,000 mm annually). Because of the altitude and seasonal clouding, the relatively cool temperatures can drop to 10ºC. Most of the area is classified as wet to very wet pre-montane or montane forest. Many of the tributaries of the San Juan River form here and supply water to operate industries, for hydroelectric energy, and groundwater recharge for high quality potable water. While the southern limit of this zone (and therefore the southern limit of the SJRB) crosses through at least 15 protected areas that are administered by MINAE (Map 14), AA, the municipalities, and the local communities are the primary actors that have direct responsibilities in the management and operation of urban and rural water systems.

Potable water sources and quality vary. Human populations in the cantons to the west and east get their potable water from springs and rivers; those in the center from wells or a combination of rivers, springs and wells; and, further to the east, potable water of poor quality is taken from rivers and shallow wells.

Hurricane threat is moderate in the extreme northwest of the zone and low to moderate elsewhere. However, landslides, mudslides and rivers overflowing their banks can be caused by tropical disturbances even if somewhat distant, which is worsened by the increased construction within the flood plains. When water logged, the steeper soils can fail, destroy water distribution systems, and fill wells and ponds with sediment. Further downstream, flooding and water logging often destroy crops.

  • Because of the volume and quality of water available in this zone, many organizations have been charged, in one way or another, with the care and management of its sources as well as with its distribution and storage.6 Most do so in coordination with AA, although in the larger cities water may be administered by the municipality.
  • Management and protection of water in the zone fall to many different groups including water committees, development committees, communities, students, and non-governmental organizations.
  • Classes are given at the health centers on the management of black and gray water and on how to use untreated water in those places where only bottled water is recommended for drinking.
  • Classes are also held on how to protect potable water sources and emphasize that trash, garbage and dead animals should not be thrown into the river.
  • Classes also include information on how to locate wells and other water sources relative to the location of latrines and corrals.
  • Health personnel monitor water quality in coordination with other organizations such as the Technical Institute, AA, and CCSS.
  • In other parts of this zone, water associations, water committees, or other institutions take on these tasks.
  • There is coordination, with respect to protection and administration of water, between the business community and the municipality.
  • There is coordination between community water committees and AA.
  • Some of the cantons have an emergency plan for flooding as well as an emergency committee made up of representatives from the Ministry of Health, Red Cross, the municipality, fire department, education centers and members of civil society.
  • A canton agricultural center has developed an education program on land use and how to avoid contamination of rivers and streams with pesticides, fertilizers, and crop residue.
  • Farmers and ranchers, together with the community in general, have taken it upon themselves to clean the riverbanks and valleys and to maintain riparian vegetation.
  • Some communities have planted crops such as manioc, bananas and beans that can better withstand heavy rains.
  • If allowed, IDA lands can be administered by a municipality or community as a forest reserve to protect their water sources.

 

5 -Often referred to as Lake Cocibolca.

6 - MAG, MINAE, IDA, ICE, SENARA, AA, the canton municipalities, and public/private energy producers, among others.