Comparison between Regionalized Minimum Reference Flow and On-Site Measurements in Hydrographic Basins of Rural Communities in the State of Goiás, Brazil

Abstract

Reference flows are important variables for assessing water availability in Brazil, as well as in rural communities in the state of Goiás (Brazil). However, as there is a lack of flowrate data and measurement points, regionalization methods have been used for forecasting the minimum reference flow (Qref) allowed for maintaining water uses. The present research covered 92 hydrographic basins within 46 selected rural communities in the state of Goiás, and 21 basins were selected for carrying out on-site flow measurements, as well as for Qref estimation following three regionalization methodologies. Results show a large variation between the values measured and estimated by the three methodologies, but the statistical analysis found regression equations of one of the methods more suitable for application in rural hydrograph basins of Goiás.

Identification of Homogeneous Regions of Specific Minimum Flows in the State of Goiás, Brazil

“…Besides, water in sufficient quantity and with adequate quality is also a requisite for human activities in its multiple uses: human and animal consumption, health, agriculture, industry, energy generation, transportation, leisure and recreation, sewage, and effluent dilution, among others. Therefore, correct water resources management becomes crucial to the development of the countries and regions as well to conservation and maintenance of water sustainable for present and future generations.In this perspective, the Identification of Homogeneous Regions of Specific Minimum Flows in the State of Goiás, Brazil Raviel Basso 1,2 , Kássia Santana 1 , Michelle Honório 1,3 , Isabella Costa 1,3 , Sanderson Leitão 4,5 , Antonio Albuquerque 4,5,* , Paulo Scalize 1,2,3,5 availability of water resources in quantity and quality is fundamental for the occurrenceof economic activities, as well as for water supply for both human and animal consumption. Watersheds function as planning and management units, assuming a fundamental role when it comes to maintaining water resources sustainablefor present and future generations.…”

“…The same minimum reference flow has been adopted by several Brazilian states: Rio de Janeiro, EspíritoSanto, Paraná, Mato Grosso, Mato Grosso do Sul, among others. However, in the states of Minas Gerais and São Paulo, the reference flow used for management of water (water allocations) is the minimum flow with seven days of duration and ten years of return (Q7.10), while some Brazilian states adopt a flow rate that equaled or exceeded 90% of the time (Q90).On the other hand,the state of Goiás has an insufficient fluviometric monitoring network according to the World Meteorological Organization (WMO; 2008), for the adequate characterization of the behavior of the minimum flows of its water courses as it was noted by Basso et al (2022). In addition, in the existing stations, some problems are observed in the collected data, such as the presence of faults (missing data), inconsistent data and short periods, thus, the collected information is not sufficient to carry out accurate analyses.…”

“…For this reason, one of the available alternatives is the estimation of flow through regionalization, a method used as a way of filling the deficit of hydrological data in places with little or no information (Eslamian and Biabanak, 2008;Samuel et al, 2011;Pruski, et al, 2012;Basso et al, 2022). The use of the method has shown satisfactory results and can provide flexibility in the decision-making process, but it does not replace the need to monitor hydrological variables (Maciel et al, 2019).…”