This paper presents a case study on the prospects of bathing in a large water course (das Velhas River, Brazil), which crosses the important metropolitan region of Belo Horizonte (25 municipalities), receiving several point and diffuse discharges. The studies were carried out based on a mathematical simulation of thermotolerant coliforms over 227 km of the river, using an adaptation of the Qual2E model (model Qual-UFMG). Simulations of intervention scenarios were made for the current conditions, with three reference flows for the das Velhas River, tributaries and direct contribution: Q7,10 (representative of low-flow conditions), Q50 (average conditions) and Q10 (rainy season). The intervention scenarios simulated were: (a) current conditions without intervention; (b) scenario with effluent disinfection in the two largest wastewater treatment plants in the basin (around 2.4 million inhabitants); (c) scenario with 95% sewage collection and treatment, with disinfection in all municipalities of the study area; (d) scenario with the calculation of values required for the coverage of sewage treatment and coliform removal efficiencies based on a mathematical optimization process. The monitoring data and results of all simulations indicated improvement in coliform concentration as the river flows downstream. However, results suggested that disinfection per se is not enough. Even under hypothetical conditions of excellent sanitary infrastructure for a developing country, coverage of collection and treatment of 95% of the generated sewage, and treatment with disinfection at all wastewater treatment plants, concentrations of thermotolerant coliforms in das Velhas River are likely to be above the maximum allowable of 1,000 MPN/100 mL for bathing purposes. The mathematical optimization indicated the need for very high percentages of sewage treatment coverage (near 100%, i.e. universality of collection and treatment) and implementation of disinfection in most treatment plants in the basin, and highlighted the fact that both items play equally important roles.
Skip Nav Destination
Article navigation
Research Article|
June 01 2013
Challenges for bathing in rivers in terms of compliance with coliform standards. Case study in a large urbanized basin (das Velhas River, Brazil)
Marcos von Sperling;
1Departamento de Engenharia Sanitária e Ambiental, Universidade Federal de Minas Gerais; Av. Antônio Carlos, 6627 – Escola de Engenharia - Bloco 1 – CEP 31270–901, Belo Horizonte, Brazil
E-mail: marcos@desa.ufmg.br
Search for other works by this author on:
Eduardo von Sperling
Eduardo von Sperling
1Departamento de Engenharia Sanitária e Ambiental, Universidade Federal de Minas Gerais; Av. Antônio Carlos, 6627 – Escola de Engenharia - Bloco 1 – CEP 31270–901, Belo Horizonte, Brazil
Search for other works by this author on:
Water Sci Technol (2013) 67 (11): 2534–2542.
Article history
Received:
September 05 2012
Accepted:
February 06 2013
Citation
Marcos von Sperling, Eduardo von Sperling; Challenges for bathing in rivers in terms of compliance with coliform standards. Case study in a large urbanized basin (das Velhas River, Brazil). Water Sci Technol 1 June 2013; 67 (11): 2534–2542. doi: https://doi.org/10.2166/wst.2013.145
Download citation file:
Sign in
Don't already have an account? Register
Client Account
You could not be signed in. Please check your email address / username and password and try again.
Impact Factor 1.915
CiteScore 3.3 • Q2
13 days submission to first
decision
1,439,880 downloads in 2021