What is the current hydrologic regime of Espirito Santo and the Rio Doce?
Knowing the actual hydrologic regime is the key first step in building models of the dynamics of water movement. This starts with climate observations - how much is it raining where with what temperature. Then, river flow is measured at specific measuring stations, or gauges. The flow records are then available through the Agência Nacional de Águas (ANA). The location of dams affected the flow regime, and must be taken into consideration in the flow routing modeling. The discharge regime of the state of Espirito Santo, and the extension of the Rio Doce into Minas Gerais is defined by the discharge records from ANA. These records then provide the basis for the VIC modeling that describes the overall hydrological cycle.Analysis of the overall flow records showed that the following stations had the most complete data records, and would be suitable for the modeling calibrations/validation process.
Note the natural logarithmic scale provided to show all gauge data on the same graph.
Download observed data by gauge station. Text files in Comma Separated Values format.
These are the following linear trends at the corresponding significance level for observed streamflow (from ANA) for 1970 – 2006
|Years available||Gauge||Linear Trend (%/year)||Student-t Significance|
|1970 – 2006||Cachoeira||-0.0249||0.9|
|1970 – 2006||Valadares||0.3784||0.8|
|1970 – 2006||Guandu||0.0884||0.8|
|1970 – 2006||Itabapoana||-0.02424||0.8|
|1970 – 2006||Leopoldina||-0.0897||0.8|
|1970 - 2006||Rive||0.1582||0.6|
|1970 – 1994||Linhares||-1.023||0.5|
The increasing streamflow occurs at gauges that are West of the basin. This corresponds to increasing precipitation from 1970 – 2006. The gauge closest to the coast experiences the highest decrease in flows – this could be due to (a) undisclosed dams/reservoirs (b) increase in sediment impeding flow to the gauge (c) poor quality gauge data or (d) a combination of (a), (b) and/or (c).