Siting, disassaying and exfilling of the Mamão Dam in Ecuador/RN

Isabel Lausanne Fontgalland,Zenon Sabino De Oliveira

doi:10.33448/rsd-v10i17.24742

Isabel Lausanne Fontgalland, Zenon Sabino De Oliveira

Open Access

https://doi.org/10.33448/rsd-v10i17.24742

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Abstract

Over four decades, there has been silting process of the riverbed that flows into the Mamão Dam, which supplies the water needs of the city of Ecuador-RN. This process has been taking place, caused largely by the receipt of mining tailings upstream of the reservoir. Thus, it became necessary the dredging consisting of removing the debris build-up and the bed debris and the riverbanks, offering a free flow to the waters that are intended for, and the excavation of the waste particles and accumulated sediment in the bed reservoir. For this, it was necessary; there were the necessary techniques for the conservation and proper maintenance so that did not occur obstruction of alluvial channel this spring. The work consisted of advice to the Municipality of the City of Ecuador, state of Rio Grande do Norte, where it made a technical feasibility study to recover the amount of previously existing water in the weir, were recovered to meet the population's consumption demand city and county. The study was conducted in 2013 and thus met the revitalization process and also the awareness of miners and miners, as the appropriate place for deposit of tailings stemmed these activities.

Highlights

The low levels of precipitation and the irregularity of its regime in the Northeast region, notably in the Brazilian semiarid region, together with the hydrogeological context, contribute to the reduced values of water availability observed there
With a population of 6,070 inhabitants, it is supplied by artesian wells from the Caiçara community and the main reservoir located in the Pau dos Ferros community, called Açude Mamao
Knowing that the concept of silting can be defined as a process of accumulation of solid particles, in an aqueous or aerial medium, occurring when the force of the natural transport agent is overcome by the force of gravity or when the supersaturation of water or air allows the deposition of solid particles (Infantil Jr & Fornasari Filho, 1998), this material brought along the natural course of the weir gutter, is composed of natural sediments of particles transported in suspension or rolling and material from mining tailings, composed of micas, quartz and feldspar, constituents of kaolin tailings

Summary

Introduction

The low levels of precipitation and the irregularity of its regime in the Northeast region, notably in the Brazilian semiarid region, together with the hydrogeological context, contribute to the reduced values of water availability observed there. The high rates of evapotranspiration normally exceed the irregular rainfall totals, configuring negative rates in the water balance (ANA, 2021). Over the years, its reservoir has been depleted due to siltation and the sedimentation of the weir bed, requiring the removal of material so that in its place, the water that previously occupied this space could be accumulated. Knowing that the concept of silting can be defined as a process of accumulation of solid particles (sediments), in an aqueous or aerial medium, occurring when the force of the natural transport agent is overcome by the force of gravity or when the supersaturation of water or air allows the deposition of solid particles (Infantil Jr & Fornasari Filho, 1998), this material brought along the natural course of the weir gutter, is composed of natural sediments of particles transported in suspension or rolling and material from mining tailings, composed of micas, quartz and feldspar, constituents of kaolin tailings. According to OLIVEIRA, (1995), silting processes lead to the following problems: loss of reservoir volume; channel depth reduction; loss of efficiency of hydraulic works; flood production; deterioration of water quality; alteration and death of aquatic life

Methodology

Results and Discussion

Conclusion