Digital cartography to estimate runoff for supporting urban planning

ABSTRACT

The research was developed in Caçula Stream basin in Ilha Solteira (SP, Brazil), focusing on runoff estimation based on digital cartography in order to produce quick and low cost chart for supporting urban planning. The runoff curve number (CN) method, from Soil Conservation Service (SCS), was used for runoff estimation using land use and soil classes occurring in the area. Land use charts were produced by satellite imagery (2001 and 2009) to consider past and present scenarios and taking in account how land use changes controls runoff. It was observed that the use modifications happened in the period resulted in changes on runoff index, mainly because of the increasing of the urban area and pasture to sugar cane use substitution. Results show strong relationship between runoff and land use changes. In general, results allowed to predict potentials and constrains for urban expansion in the area, indicating specific areas which need detailed studies for local problems solve.

Keywords:
runoff; environmental degradation; urban planning; Ilha Solteira