north to the town of Villa Riva before turning southeast and receiving the Payabo River on its right bank. The Yuna next passes beneath Autopista Juan Pablo II upon briefly entering the municipality of Arenoso and continues east passing several small villages including Los Coles and Agua Santa del Yuna. The Yuna continues east into the village of Los Cacaos where the Yuna serves as the Duarte–Samaná Province line in a region filled with marshlands and cienegas. The Yuna next arrives at the long Barracote River which separates from the right bank of the Yuna. The Barracote runs southeast-east as it reaches its mouth at the Samaná Bay (Spanish: Bahía de Samaná) in the municipality of Sánchez at an elevation of above sea level. The main branch of the Yuna continues northeast receiving the Guayabo River on its left bank before traveling east into Samaná Province. The Yuna finally reaches its delta within Los Haitises National Park approximately south of the city of Sánchez and north of the Barracote River mouth. The delta is located within the Lower Yuna Mangroves (Spanish: Manglares del Bajo Yuna) and empties into the Samaná Bay., which is one of the largest estuaries in the Caribbean. There is a long period when the Yuna River provides Samana Bay with a flow of stable and low freshwater, as well as two times of the year when the Yuna River rises and provides the Bay with a flow of large freshwater. In total the Yuna River, is 208 km long. Rice irrigation A primary usage for the Yuna River, where it travels along the city of Bonao, is for the cultivation of rice. Noted by Barzman and Peguero (1995) in Impacts of Altered Freshwater Flows to Estuaries: Yuna River Watershed and Samana Bay (Jim Tobey, 2004) “agrochemical use for rice cultivation in the Yuna watershed is contributing to loss in soil fertility and to increases in pests, weeds, and diseases, which, in turn, require increases in the already high use of the same agrochemicals.” (Tobey, 2004, 31) Geology Although most of the Yuna River bed is vegetated, but there is a high amount of gravel south of Bonao. References Rivers of the Dominican Republic Geography of Monseñor Nouel Province Geography of Sánchez Ramírez Province Geography of Samaná Province Geography of Duarte Province