Technical coefficients of direct use of water in monetary terms for river basin districts in areas of irrigation for agriculture and urban water supply: the case of one of the recipients of the North Basin of The North Axis of São Francisco Transboundary Project

ABSTRACT

The São Francisco Transboundary Project (SFTP) is a Federal Government project, which includes two diversions of the River to supplement the supply of local water in Ceará, Rio Grande do Norte, Paraíba and Pernambuco. The North branch will deliver water to Piranhas-Açu (Paraiba and Rio Grande do Norte States) and Jaguaribe (Ceará State) reservoirs, which will become the largest recipients of the transboundary. In this paper we propose methodologies by which technical coefficients of direct use of water in different hydrographic regions of the Piranhas-Açu basin under study can be stated in monetary terms for the economic sectors associated with urban supply (US) and the agricultural irrigation (AI). The technical coefficients we have calculated are a different means of presenting well-established coefficients in the basics of Input-Output Analysis. In the case of economic sectors associated with the US, the coefficients showed that at a certain level of urbanization, the amountof water used increases more than the economic product of the sector. The coefficients of AI obtained are much lower than those of the USand, when calculated by crop, showed that in the basin, trhee is an inadequate mix of crops and a low water use efficiency, resulting in low economic value per cubic meter of water allocated to the sector. This implies, for both economic sectors, a need for incentives to use water in a more efficient way in the basin.

Keywords:
technical coefficients; water use; economic return; irrigation; urban water supply; allocation policies