Characterization of Bahía Blanca main existing pressures and their effects on the state indicators for surface and groundwater quality

LIMBOZZI, F.; LEITÃO, T.E.

Perspectives On Integrated Coastal Zone Management In South America

IST PRESS

Año: 2008; p. 315 - 331

Coastal zone water quality depend directly on existing local pressures but also on pressuresoriginated in the drainage watershed basins, which effects are transported to the estuarymostly by rivers and by groundwater. This chapter characterizes the pressures originated fromthe watershed upgradient to the coastal area of Bah ́a Blanca estuary, in terms of quantity andıquality. The state indicators characterization allowed a diagnosis of the reference situationin what concerns the surface water and groundwater quality that can potentially contribute ̃to the estuary (Leitao et al. 2007). For this aim, the DPSIR (Driver-Pressure-State-Impact-Responses) methodology is applied. The state indicators used reflect the present situationof the inland waters due to the existing pressures and the actual conditions of the systems.Quantity indicators assess the changes in water amount due to changes in the pressures. Forgroundwater, the quantity ?state? indicator proposed is the piezometric level, while for surfacewater the chosen indicator is the flowrate discharge of rivers into the estuary. The changesin land use for agriculture and for livestock, as well as the placement of city sewage treat-ment plant are the selected scenarios for the case of Bah ́a Blanca estuary, being the qualityıindicators chosen in order to reflect the effects of these pressures.