Isobel Brink

Stellenbosch University | SUN · Department of Civil Engineering

This paper presents a comparison of six plant biofilter designs for urban stormwater quality improvement and reports on their performances. Thirty-six columns were populated with the endemic South African plant Prionium serratum, representing plant biofilter designs that incorporate different pollutant removal mechanisms in the biofiltration proces...

Oil and grease (O&G) removal efficiencies using 4 automobile stormwater treatment systems were investigated and compared. The treatment systems used were: low-cost granular activated carbon–rice husk (GAC–RH) filter system, river gravel–granular activated carbon (GR–GAC) filter system, rice husk only (RH) filter system and the conventional PVC O&G...

An investigation into the pollution of stormwater runoff from automobile workshops in Nigeria was performed. Also, multivariate regression was used to predict the pH, oil, and grease (O&G) as well as the electrical conductivity (EC) in relation to the characteristics of the solids and metals pollutants of the untreated automobile workshop stormwate...

In South Africa, rapid environmental degeneration caused by anthropogenic pollution poses a major ecological engineering problem, demanding proper resource mitigation strategies. For the treatment of polluted water and degraded soil systems, green infrastructure (GI) offers an effective, sustainable and affordable nature-based alternative to grey i...

In South Africa, urban activities contribute high levels of pollution to rivers and groundwater via stormwater runoff. In reducing urban stormwater loads of engineered plant biofiltration, an effective and self-sustaining component of green infrastructure is a treatment option. The country's extensive natural biodiversity offers untapped potential...

The present study evaluated engineered media for plant biofilter optimisation in an unvegetated column experiment to assess the performance of loamy sand, perlite, vermiculite, zeolite and attapulgite media under stormwater conditions enriched with varying nutrients and metals reflecting urban pollutant loads. Sixty columns, 30 unvegetated and 30 J...

Urban water managers, engineers and conservation ecologists in the Western Cape (WC) Province of South Africa are faced with a major environmental and human health challenge, with urbanisation, industrialisation, population growth and agricultural development placing pressure on the limited water and soil resources. In addressing this resource degr...

The design and construction of low-cost laboratory-scale filter columns using locally available Nigerian filter materials - granular activated carbon (GAC), gravel (GR) and rice husk (RH) - were carried out and reported. The filter materials and columns were designed, constructed and used for the treatment of stormwater runoff from selected automob...

The efficiency of combined filtration media consisting of Rice Husk (RH), Granular Activated Carbon (GAC) and Gravel (GR) for the removal of metals cadmium, copper, lead and iron from stormwater runoff emanating from automobile workshops in Nigeria was investigated. Stormwater runoff samples were collected from five sites over a period of nine (9)...

This work presents mathematical modelling of Escherichia coli (E.coli) removal by a multi-barrier point-of-use drinking water system. The modelled system is a combination of three treatment stages: filtration by geotextile fabric followed by filtration and disinfection by silver-coated ceramic granular media (SCCGM) then granular activated carbon (...

In South Africa, fertiliser and herbicide pollutants resulting from agricultural practices indirectly lead to the degradation of surface freshwater and groundwater quality. Nitrogen and phosphorus, and glyphosate, derived from agricultural fertiliser and herbicide applications, respectively, contribute to watercourse toxicity. Adjacent to many of t...

A low-cost multi-barrier drinking water system incorporating geotextile fabric for pre-filtration, silver-coated ceramic granular media (SCCGM) for filtration and disinfection, granular activated carbon (GAC) as an adsorption media and a safe storage compartment for treated water has been developed and tested. The developed system offers a novel co...

Stormwater quality has been researched for decades, but design innovation has stagnated. The design engineer is commonly faced with a large array of design options, each with complex mechanisms requiring specialised knowledge, often in fields that do not form part of civil engineering training. Adequately combining and establishing the necessary kn...

The performance of plants to remove, remediate or immobilise environmental contaminants in a growth matrix through natural biological, chemical or physical activities was studied in a laboratory phytoremediation system. This study aimed to develop a novel phytoremediation system capable of investigating the remediation of agricultural pollutants by...

A gravity-driven wood filtration system, incorporating granular activated carbon (GAC) as an appropriate point of-use technology for the rural poor, has been designed, tested and optimized. Four systems were assessed in respect of metal, bacteria and particle removal when exposed to polluted river water with and without GAC. These were evaluated us...

This study appraised optimisations of numerical solutions of the one-dimensional advection–dispersion model (AD-Model) to synthetic data generated using an analytical solution. The motivation for the work was to identify reliable methods for estimating stream solute transport parameters from observed events in small rivers. Numerical solutions of t...

Three novel and two commercially available low-cost point-of-use (PoU) water treatment technologies were comparatively evaluated using a specialized comparison framework targeted at them. The comparison results and specialized framework have been discussed. The PoU systems were evaluated principally in terms of performance, flow rate and cost per v...

The study investigated two engineered fabrics and five cloth fabrics for low cost drinking water treatment. An optimized fabric filtration method has been developed and tested. Numerical models for predicting particulate removal efficiency have been developed for each fabric as support tools for selecting optimal process configuration. Both enginee...

Inadequate wastewater treatment is a major problem in South Africa. Existing wastewater treatment facilities often lack sufficient skilled labour, resulting in partially treated effluent. Increasing eutrophication in surface water bodies indicates that this problem needs rectification. The characteristics of the high-rate algal pond (HRAP) technolo...

Two low-cost sand filtration systems incorporating granular activated carbon (GAC) and non-woven geotextile respectively were assessed for Point-of-Use water treatment. Laboratory scale models were evaluated in respect of selected heavy metals, bacterial and particulate removal when exposed to surface water for five months. System 1 (ISSF-1) incorp...

The study examined two low-cost point-of-use water treatment systems developed in respect of bacterial and particulate removal when exposed to surface water for three months. Bacterial removal efficiency was estimated using E. coli and fecal coliforms, while particulate reduction efficiency was estimated by determining turbidity and total suspended...

Presented in this paper are the results of correlational analyses and logistic regression between metal substances (Cd, Cu, Pb, Zn), as well as suspended solids removal, and physical pond parameters of 19 stormwater retention pond case studies obtained from the International Stormwater BMP database. Included are cross-correlations between metals an...

Use of the concentration parameter has in the past generally been favoured in stormwater structure efficiency determinations, and specifically with use of the Effluent Probability Method. However, efficiency is by definition related to the amount of substance removed within a stormwater structure, and concentration, being a mathematical construct,...

This technical note contains findings from a larger research project into the design of stormwater detention and retention ponds for removal of metals and solids. The project required a standard system with which case studies obtained from the International Stormwater BMP Database could be compared in terms of efficiency. A novel classification sys...