Instream flow and water availability in the Rio das Pedras basin, Guarapuava-PR, Brazil

  • Leandro Redin Vestena Universidade Estadual do Centro-Oeste
  • Ederson Dias de Oliveira Universidade Estadual de Maringá
  • Marcia Cristina da Cunha Universidade Estadual do Centro-Oeste
  • Edivaldo Lopes Thomaz Universidade Estadual do Centro-Oeste
Keywords: instream flow, river regime, hydrographic basin, river ecosystem

Abstract

Knowledge of instream flow is of paramount importance to determine water availability for water resources management. This study estimated instream flow and evaluated water availability in the stretch of the Rio das Pedras, which supplies water to Guarapuava, a town in the mid-southern region of the state of Paraná, Brazil. Several different methods were employed to obtain instream flow, a reference discharge for water consumption permit, and the river regime. Methods comprised 7-day mean minimum with a 10-year return period, discharges associated to 95% and 90% permanence, yearly 7-day mean minimum discharge and basic water discharge. Discharge data were obtained from the meteorological station at the Water Station of Guarapuava (ETA). Results show that yearly river debit between 1985 and 2009 had a daily mean of 9.12 m³ s-1 and a median discharge of 9.16 m³ s-1. Estimated instream flow, measured by methods used for the Rio das Pedras stretch, ranged from 1.72 to 2.74 m³ s-1, with an average of 2.20 m³ s-1 and a coefficient of variation of 19.5%. Discharge for the stretch was estimated as 0.91 m³ s-1, following criteria used in the state of Paraná. The relationship of the evaluated stretch between daily flow and the intake volume granted by the government revealed the inefficiency of the applied methods for instream flow assessment. In fact, they failed to warrant a minimum water volume required for the conservation of the river ecosystem.

Author Biographies

Leandro Redin Vestena, Universidade Estadual do Centro-Oeste
Geógrafo e mestre em Geografia pela UFPR. Doutor em Engenharia Ambiental pela UFSC. Professor do Programa de Pós-Graduação em Geografia da UNICENTRO.
Ederson Dias de Oliveira, Universidade Estadual de Maringá
Licenciado em Geografia pela FAFIJAN. Mestre em Geografia pela UNICENTRO. Doutorando em Geografia pela UEM.
Marcia Cristina da Cunha, Universidade Estadual do Centro-Oeste
Graduada em Geografia pela FECILCAM. Mestre em Geografia pela UNICENTRO. Professora do Departamento de Geografia da UNICENTRO.
Edivaldo Lopes Thomaz, Universidade Estadual do Centro-Oeste
Graduado em Geografia pela UEL. Mestre e Doutor em Geografia Física pela USP. Professor do Programa de Pós-Graduação da UNICENTRO.
Published
26/12/2012
Section
Papers