Jima and Camú riverbanks and other farming zones in La Vega and San Francisco de Macorís. It would also allow the addition of another turbine with a 10 MW capacity at Rincón dam
providing an estimated annual 21 GWH CDE, www.hidroelectrica.gov.do accessed February 5, 2004.
There was concern that the dam would reduce the flow of water needed downstream. INDHRI was unable to counter this concern and provide communications and outreach to local
stakeholders. As a consequence the development proposal has been dropped for the moment.
6.5 Deforestation and Sedimentation
Deforestation is recognized as one of the most significant causes of alteration of natural habitat in the country. Eighty percent of the country was covered in forest in 1900, 69 percent in
1940, and 27.5 percent in 1996 SEMARN, 2001. An estimated 53 percent of the total land area is best suited for forest cover. However, only an estimated 14 percent of the surface area is
covered in forest US Army Corps of Engineers, 2002. Of that amount, only one-third of the forests are undisturbed by fire or slash and burn agriculture. The causes of deforestation are
cutting for fuel wood, charcoal production, and unsustainable agricultural practices. The Dominican Republic is mountainous, and much of the soil is poor, shallow, and easily eroded.
The key impacts of deforestation on hydrological cycles and resources include: • A decrease in infiltration and recharge of aquifers, causing drier than expected soil
conditions • An increase in the volume and velocity of surface runoff
• A decrease in uniformity of stream flow very low during dry periods and more frequent and intense flooding during wet periods
These changes also lead to increased sedimentation of streams and rivers. Studies of seven deforested basins showed a loss of surface soil of 100-500 tonshayr Alvarez, 2000. It is
estimated that 86 percent of the surfaces of the country’s drainage basins have problems of
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degradation Alvarez, 2000. Some of the watersheds where environmental degradation is most serious are the Yaque del Norte, Nizao and the Yuna. We have not seen any studies on the
impacts of sedimentation on the estuary. The Hatillo and Rincón reservoirs are trapping sediment from the upper watershed. However, periodic flooding releases large quantities of sediment to the
lower Yuna and Samana Bay causing irrigation canals in the lower Yuna irrigation district to be obstructed Office of the President, 2002. Following flooding, distinct sediment plumes can be
observed in the southwest portion of the Bay of Samana such as following the flooding that occurred at the end of November 2003.
Adequate freshwater inflows are important to most marine and aquatic systems at the saltwater-freshwater interface. For example, it can be important to flush the salts in mangroves.
Alterations in flow rates can destroy marine communities. Sedimentation can cover marine communities that depend upon clear water. Seagrass beds and coral reefs are two such
communities threatened in this manner. In the last decade the problems of deforestation have abated. By the end of the 1990s thee
is evidence that the land area under forest cover was greater than that of 1980, suggesting that a recovery was occurring IRG, 2001. Reasons for the stabilization and recovery of forests include
IRG, 2001: • Migration of rural residents, especially hillside agriculturists, to the cities
• Reforestation and natural resource management programs • Expansion in the number and size of protected areas
• Reduced taxes on the importation of low cost food commodities which, in turn, contributed to a reduction in steep slope subsistence agriculture
• Subsidized bottled cooking gas which, in turn, virtually eliminated the demand for charcoal charcoal consumption dropped from 1.6 million sacks in 1982 to 26 thousand
sacks in 2000
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6.6 Overfishing
