Keywords: water quality, pollution, suburban catchments, phosphate, monitoring
Water quality management in the Balabandere Creek catchment
Understanding hydrological and hydrochemical processes has become increasingly more challenging with high rates of population growth and subsequent alteration of the environment. In addition to maintaining monitoring networks to assess the general state of water quality, detecting trends, and computing pollutant transport, process-level information is needed to evaluate factors that affect the transport and transformation of solutes in aquatic environments. In this study, conducted in the Balabandere Creek catchment, a monitoring program was performed in order to assess pollution sources along the creek longitudinal profile. Balabandere Creek is a typical suburban creek, located near Istanbul. Four sampling points were selected along the creek longitudinal profile, and physical, chemical and bacteriological analyses were made on grab water samples taken at 15-day intervals for seven months. This monitoring process was designed to provide basic inventory information suitable for catchment scale water quality management, and, in addition, to help to support the formulation of legal regulations for policy planning and practice. The land use in the catchment and possible nutrient sources were taken into account when considering the sampling points. The nutrient load of the first sampling point, draining the managed mixed broadleaved forest, was significantly lower than the other points (total nitrogen ?1 = 0.04, ?2 = 0.18, ?3 = 0.09, ?4 = 0.66 ppm) despite the dilution effect. Evaluation of the water quality parameters are discussed and the cumulative effects of various land use types are proposed. With the aid of this monitoring process, the catchment as a system was delineated and possible pollution sources were identified. The measures required to decrease the pollution of the creek are discussed. The situation and legislation for these kinds of problems in Turkey are also assessed.