Author(s): S. Violeta Dominguez Talavera
Linked Author(s): Iris Dominguez
Keywords: Water environment; Urbanization; Hydraulic structures; Design criteria; Sustainability
Abstract: The city of Ica is located 300 km south from Lima, capital of Peru. The valley of Ica is at the coast, an arid region. But, it is one of the most fertile valleys in Peru thanks to its climate and the rainfall in the Andes of Huancavelica, from December to March of the following year. The Ica River is a seasonal river. The main water use is agricultural. Around September to November, the water in the river comes from a lagoon in Huancavelica by means of a regulation system. The rest of the time, the river runs dry. Though the flooding in January 1998, because of El Nino, riversides in the area nearby the city center and periphery are densely populated. The rapid growth of the city is connected with the economy in the valley. The city has received the migration of people who mostly work in export agriculture, which mainly uses groundwater. Water supply demand, wastewater and waste production have risen in Ica. In this article, hydraulic structures are described regarding the situation of the Ica River environment and the urbanization in the valley of Ica, with the purpose to make recommendations for the design of hydraulic structures that contribute to the sustainability of the urban water environment in Ica. In the Ica Valley, the state service of hydrology operates one station of river flow measurement. More stations are needed in the valley. It is necessary to measure the sediment transport, too. Information about the hydraulic structures in the valley was collected. Within the context of the Ica Valley and the existing hydraulic structures, field work investigations focused on the urban section of the river of about five kilometer long, between the bridges Socorro and Los Maestros, in particular, on the Puno Bridge and the Tacaraca hydraulic system, both inaugurated in 2010. The Puno Bridge cuts in two parts a river section of one kilometer length. People, who benefit, welcome it, but in general people also argue the bridge may not have enough capacity of discharge during the rainfall season because of its form and size. The hydraulic system of Tacaraca lost one gate two months after set in operation and Ica’s people were put under flood alarm, because the remaining gates could not open as soon as the water level was rising on February 8, 2011. Moreover, rural and urban areas were flooded downstream. This flow of 118 m3/s in February is between the 2-year and 5-year return period flow. Regarding the design, construction, operation and maintenance of hydraulic structures, such as bridges, river flood defenses, barrages, water intake structures, canals, etc., it is recommended that the design takes into account the river environment as well as the urbanization process in the Ica River Valley. The design should be based on simulation – to be validated in the field – of the river morphology, hydraulics and sediment transport. Simulation allows the analysis of design criteria as well as of scenarios of impact on the urban water environment in Ica.
Year: 2013