Examining the efficacy of the legal framework governing the management of greywater in South Africa's informal settlements.

The management of greywater and sanitation in South Africa's urban informal settlements is a pressing concern. This review critically examines the legal framework that governs greywater management in South Africa's informal settlements, aiming to shed light on the existing regulations, gaps, and opportunities for sustainable greywater reuse. By scrutinizing the legal framework, the review identifies gaps and challenges in the regulatory environment, including inconsistencies, lack of clarity, and limited enforcement mechanisms. It explores the potential for international best practices to inform possible amendments to the existing legal framework. This was a quantitative research design utilizing a cross sectional survey model. Questionnaires were administered electronically to a sample of 17 municipal leaders from the City of Tshwane, City of Johannesburg and Buffalo City municipalities whose responsibilities were on water management. Descriptive statistics were employed in analysis of the data. Outcomes were reviewed against the alignment or the lack thereof with the SANS 1732:201x standards. This paper underscores the critical need for a coherent and robust legal framework to support responsible greywater management in South Africa's informal settlements. The paper's insights contribute to the ongoing discourse on water governance, shedding light on the pathways toward a more equitable water future.

Using terrestrial laser scanning in inventorying of a hybrid constructed wetland system.

The goal of this paper was to evaluate the possibility of using terrestrial laser scanning (TLS) for inventorying of a hybrid constructed wetland (CW) wastewater treatment plant. The object under study was a turtle-shaped system built in 2015 in Eastern Poland. Its main purpose is the treatment of wastewater from the Museum and Education Centre of Polesie National Park. The study showed that the CW system had been built in compliance with the technical documentation, as differences between values obtained from the object and those given in the design project (max. ± 20 cm for situation and ±5 cm for elevation) were within the range defined by the legislator. It was also shown that the results were sufficiently precise to be used for as-built surveying of the aboveground elements of the CW system. The TLS technique can also be employed to analyse quantitative changes in object geometry arising during long-term use (e.g. landmass slides or erosion), the identification of which can help in selecting the hot-spots at risk of damage and thus restore the object to its original state as well as prevent new changes.

Microbiological and physicochemical evaluation of the effluent quality in a membrane bioreactor system to meet the legislative limits for wastewater reuse.

The aim of this study was to assess the efficacy and effluent quality of a pilot-scale intermittently aerated and fed, externally submerged membrane bioreactor (MBRes) treating municipal wastewater. The effluent quality of the MBRes was evaluated regarding system ability to comply with the Greek legislative limits for restricted and unrestricted wastewater reuse. The average permeate flux was 13.9 L m-2 h-1, while the transmembrane pressure remained above the level of -110 mbar. Experimental data showed that biochemical oxygen demand, chemical oxygen demand, total nitrogen, PO43-- P and total suspended solids removal efficiencies were 97.8, 93.1, 89.6, 93.2 and 100%, respectively, whereas turbidity was reduced by 94.1%. Total coliforms and Escherichia coli were fully eliminated by ultrafiltration and disinfection methods, such as chlorination and ultraviolet radiation. In agreement with the Greek legislation (Joint Ministerial Decree 145116/11) and the guidelines recommended for the Mediterranean countries, the disinfected effluent of the MBRes system can be safely reused directly for urban purposes.

Hospital effluents management: Chemical, physical, microbiological risks and legislation in different countries.

Hospital wastewater (HWW) can contain hazardous substances, such as pharmaceutical residues, chemical hazardous substances, pathogens and radioisotopes. Due to these substances, hospital wastewater can represent a chemical, biological and physical risk for public and environmental health. In particular, several studies demonstrate that the main effects of these substances can't be neutralised by wastewater treatment plants (WWTPs). These substances can be found in a wide range of concentrations due to the size of a hospital, the bed density, number of inpatients and outpatients, the number and the type of wards, the number and types of services, the country and the season. Some hazardous substances produced in hospital facilities have a regulatory status and are treated like waste and are disposed of accordingly (i.e., dental amalgam and medications). Legislation is quite homogeneous for these substances in all industrial countries. Problems that have emerged in the last decade concern substances and microorganisms that don't have a regulatory status, such as antibiotic residues, drugs and specific pathogens. At a global level, guidelines exist for treatment methods for these effluents, but legislation in all major industrial countries don't contain limitations on these parameters. Therefore, a monitoring system is necessary for these effluents as well as for substances and pathogens, as these elements can represent a risk to the environment and public health.

Overview of legislation on sewage sludge management in developed countries worldwide.

The need to apply innovative technologies for maximizing the efficiency and minimizing the carbon footprint of sewage treatment plants has upgraded sewage sludge management to a highly sophisticated research and development sector. Sewage sludge cannot be regarded solely as 'waste'; it is a renewable resource for energy and material recovery. From this perspective, legislation on sewage sludge management tends to incorporate issues related to environmental protection, public health, climate change impacts and socio-economic benefits. This paper reviews the existing legislative frameworks and policies on sewage sludge management in various countries, highlighting the common ground as well as the different priorities in all cases studied. More specifically, the key features of legislation regarding sludge management in developed countries such as the USA, Japan, Australia, New Zealand and the European Union (EU27) are discussed.

Global ballast water management and the "same location" concept: a clear term or a clear issue?

The United Nations recognized the transfer of harmful organisms and pathogens across natural barriers as one of the four greatest pressures to the world's oceans and seas, causing global environmental changes, while also posing a threat to human health, property, and resources. Ballast water transferred by vessels was recognized as a prominent vector of such species and was regulated by the International Convention for the Control and Management of Ship's Ballast Water and Sediments (2004). Permanent exceptions from ballast water management requirements may apply when the uptake and discharge of ballast water occur at the "same location." However, the "same location" concept may be interpreted differently, e.g., a port basin, a port, an anchorage, or a larger area even with more ports inside. Considering that the Convention is nearing the beginning of enforcement, national authorities all around the world will soon be exposed to applications for exceptions. Here we consider possible effects of different interpretations of the "same location" concept. We have considered different possible extensions of the same location through environmental, shipping, and legal aspects. The extension of such areas, and the inclusion of more ports, may compromise the Convention's main purpose. We recommend that "same location" mean the smallest practicable unit, i.e., the same harbor, mooring, or anchorage. An entire smaller port, possibly also including the anchorage, could be considered as same location. For larger ports with a gradient of environmental conditions, "same location" should mean a terminal or a port basin. We further recommend that IMO consider the preparation of a guidance document to include concepts, criteria, and processes outlining how to identify "same location," which limits should be clearly identified.

Counting at low concentrations: the statistical challenges of verifying ballast water discharge standards.

Discharge from the ballast tanks of ships is one of the primary vectors of nonindigenous species in marine environments. To mitigate this environmental and economic threat, international, national, and state entities are establishing regulations to limit the concentration of living organisms that may be discharged from the ballast tanks of ships. The proposed discharge standards have ranged from zero detectable organisms to < 10 organisms/ m3. If standard sampling methods are used, verifying whether ballast discharge complies with these stringent standards will be challenging due to the inherent stochasticity of sampling. Furthermore, at low concentrations, very large volumes of water must be sampled to find enough organisms to accurately estimate concentration. Despite these challenges, adequate sampling protocols comprise a critical aspect of establishing standards because they help define the actual risk level associated with a standard. A standard that appears very stringent may be effectively lax if it is paired with an inadequate sampling protocol. We describe some of the statistical issues associated with sampling at low concentrations to help regulators understand the uncertainties of sampling as well as to inform the development of sampling protocols that ensure discharge standards are adequately implemented.

Approaches to setting organism-based ballast water discharge standards.

As a vector by which foreign species invade coastal and freshwater waterbodies, ballast water discharge from ships is recognized as a major environmental threat. The International Maritime Organization (IMO) drafted an international treaty establishing ballast water discharge standards based on the number of viable organisms per volume of ballast discharge for different organism size classes. Concerns that the IMO standards are not sufficiently protective have initiated several state and national efforts in the United States to develop more stringent standards. We evaluated seven approaches to establishing discharge standards for the > 50-microm size class: (1) expert opinion/management consensus, (2) zero detectable living organisms, (3) natural invasion rates, (4) reaction-diffusion models, (5) population viability analysis (PVA) models, (6) per capita invasion probabilities (PCIP), and (7) experimental studies. Because of the difficulty in synthesizing scientific knowledge in an unbiased and transparent fashion, we recommend the use of quantitative models instead of expert opinion. The actual organism concentration associated with a "zero detectable organisms" standard is defined by the statistical rigor of its monitoring program; thus it is not clear whether such a standard is as stringent as other standards. For several reasons, the natural invasion rate, reaction-diffusion, and experimental approaches are not considered suitable for generating discharge standards. PVA models can be used to predict the likelihood of establishment of introduced species but are limited by a lack of population vital rates for species characteristic of ballast water discharges. Until such rates become available, PVA models are better suited to evaluate relative efficiency of proposed standards rather than predicting probabilities of invasion. The PCIP approach, which is based on historical invasion rates at a regional scale, appears to circumvent many of the indicated problems, although it may underestimate invasions by asexual and parthenogenic species. Further research is needed to better define propagule dose-responses, densities at which Allee effects occur, approaches to predicting the likelihood of invasion from multi-species introductions, and generation of formal comparisons of approaches using standardized scenarios.

Ballast water regulations and the move toward concentration-based numeric discharge limits.

Ballast water from shipping is a principal source for the introduction of nonindigenous species. As a result, numerous government bodies have adopted various ballast water management practices and discharge standards to slow or eliminate the future introduction and dispersal of these nonindigenous species. For researchers studying ballast water issues, understanding the regulatory framework is helpful to define the scope of research needed by policy makers to develop effective regulations. However, for most scientists, this information is difficult to obtain because it is outside the standard scientific literature and often difficult to interpret. This paper provides a brief review of the regulatory framework directed toward scientists studying ballast water and aquatic invasive species issues. We describe different approaches to ballast water management in international, U.S. federal and state, and domestic ballast water regulation. Specifically, we discuss standards established by the International Maritime Organization (IMO), the U.S. Coast Guard and U.S. Environmental Protection Agency, and individual states in the United States including California, New York, and Minnesota. Additionally, outside the United States, countries such as Australia, Canada, and New Zealand have well-established domestic ballast water regulatory regimes. Different approaches to regulation have recently resulted in variations between numeric concentration-based ballast water discharge limits, particularly in the United States, as well as reliance on use of ballast water exchange pending development and adoption of rigorous science-based discharge standards. To date, numeric concentration-based discharge limits have not generally been based upon a thorough application of risk-assessment methodologies. Regulators, making decisions based on the available information and methodologies before them, have consequently established varying standards, or not established standards at all. The review and refinement of ballast water discharge standards by regulatory agencies will benefit from activity by the scientific community to improve and develop more precise risk-assessment methodologies.

Critical review: regulatory incentives and impediments for onsite graywater reuse in the United States.

Graywater is a potential water source for reducing water demand. Accordingly, a review was undertaken of graywater reuse regulations and guidelines within the 50 United States. Major issues considered included acceptability for graywater segregation as a separate wastewater stream, allowable graywater storage, onsite treatment requirements, and permitted graywater use applications. Existing regulations and plumbing codes in the different states suggest that there are impediments to overcome but also potential incentives for graywater reuse. It is encouraging that regulations in 29 states promote safe graywater reuse, but there are also inconsistencies between plumbing codes and other regulations within and among the 50 states. Impediments to graywater reuse include disallowances of graywater segregation or collection, and restriction of graywater reuse to mostly subsurface irrigation with limited indoor use permission. Ease on restrictions and guidelines to promote development of low-cost and proven treatment technologies are needed to promote graywater reuse.

The role of ownership in environmental performance: evidence from coalbed methane development.

One way coalbed methane production differs from traditional oil and gas extraction is in the large quantities of produced water. This water must be disposed of for production to occur. Surface discharge has proven to be a low-cost alternative; regulations are in place to protect surface water quality. This paper investigates the effects of alternative ownership regimes on regulatory compliance. A unique dataset linking coalbed methane wells in Wyoming to water disposal permit violations is used to explore differences in environmental performance across severed and unified minerals. Empirical analysis of these data suggest that ownership does impact environmental compliance behavior. Most violations occur on split estate. Federal split estate wells have more severe violations, though not necessarily more of them. Federal unified wells performed best, with fewer and less serious violations. Wells on private land have more, though not necessarily more severe, violations. These results suggest some room for policy proposals accounting for alternative ownership regimes.

Modelling micro-pollutant fate in wastewater collection and treatment systems: status and challenges.

This paper provides a comprehensive summary on modelling of micro-pollutants' (MPs) fate and transport in wastewater. It indicates the motivations of MP modelling and summarises and illustrates the current status. Finally, some recommendations are provided to improve and diffuse the use of such models. In brief, we conclude that, in order to predict the contaminant removal in centralised treatment works, considering the dramatic improvement in monitoring and detecting MPs in wastewater, more mechanistic approaches should be used to complement conventional, heuristic and other fate models. This is crucial, as regional risk assessments and model-based evaluations of pollution discharge from urban areas can potentially be used by decision makers to evaluate effluent quality regulation, and assess upgrading requirements, in the future.

Management experiences and trends for water reuse implementation in Northern California.

In 2010, California fell nearly 300,000 acre-ft per year (AFY) short of its goal to recycle 1,000,000 AFY of municipal wastewater. Growth of recycled water in the 48 Northern California counties represented only 20% of the statewide increase in reuse between 2001 and 2009. To evaluate these trends and experiences, major drivers and challenges that influenced the implementation of recycled water programs in Northern California are presented based on a survey of 71 program managers conducted in 2010. Regulatory requirements limiting discharge, cited by 65% of respondents as a driver for program implementation, historically played an important role in motivating many water reuse programs in the region. More recently, pressures from limited water supplies and needs for system reliability are prevalent drivers. Almost half of respondents (49%) cited ecological protection or enhancement goals as drivers for implementation. However, water reuse for direct benefit of natural systems and wildlife habitat represents just 6-7% of total recycling in Northern California and few financial incentives exist for such projects. Economic challenges are the greatest barrier to successful project implementation. In particular, high costs of distribution systems (pipelines) are especially challenging, with $1 to 3 million/mile costs experienced. Negative perceptions of water reuse were cited by only 26% of respondents as major hindrances to implementation of surveyed programs.

Assessing the risk of ballast water treatment to human health.

Ballast water management systems utilizing noxious chemicals have to be approved according to the Ballast Water Convention by the International Maritime Organization (IMO). The approval procedure requires human health risk assessment. Our objective was to evaluate the existing human health risk assessment process for ballast water management systems. Towards this end, we analyzed the available applications for IMO approval. Since the majority of active substances currently in use are oxidative compounds the corresponding treatment systems generate and release a large number of disinfection by-products. The application dossiers only select a number of by-products for risk assessment. We propose a more comprehensive approach based on the type of ballast water management system, the quality of water treated and the toxicity of compounds discharged into the environment. Subsequent to effects assessment we propose to classify substances according to a hazard evaluation procedure, based on an approach used for maritime transport. We identified a need for better exposure assessment. This requires knowledge of exposure situations. We provide a comprehensive listing of occupational and non-occupational exposure settings and quantification models for exposure assessment.

Will stringent total nitrogen wastewater treatment plant discharge regulations achieve stream water quality goals?

The Colorado Department of Public Health and Environment (CDPHE) proposed the in-stream numeric nutrient criteria as 2 mg TN per L and 0.16 mg TP per L for warm surface waters and 0.40 mg TN per L and 0.11 mg TP per L for cold surface waters. Consequently the department presented the nutrient limits for the municipal wastewater treatment plants (WWTPs) as annual averages of 0.7 mg TP per L and 5.7 mg TIN per L and quarterly averages of 1.0 mg TP per L and 9.0 mg TIN per L. Implementing stringent nutrient reduction at point sources is unlikely to result in improvements to the environment without non-point source controls. In this study, total nitrogen (TN) load inputs from known point source, WWTPs, and other non-point sources at six sub-basins of the Cache La Poudre (CLP) River Basin were estimated and compared under various hydrologic conditions. Significant loading exceedance from the proposed limits was observed during lower flow conditions and other sources dominated during events when the exceedance was observed except for one point. The point receives direct TN inputs from a WWTP which has the highest TN concentration in its effluent among all WWTPs in the study area; however, TN loads entered the point from other sources were significant during higher flow conditions. TN loads in the CLP River were simulated to determine whether the loads meet the proposed in-stream limits in a case in which all WWTPs comply with the proposed regulations for WWTPs. From this study, it was observed that reducing TN concentrations only at WWTPs merely impacts total TN loads in the river.

The evolution of septic systems practices in Ohio.

Regulations that address management of wastewater in rural areas in Ohio are in the process of being updated. The study described in this article reviewed the legal and regulatory process that occurred in the past decade. Thirty percent of septic systems in Ohio are failing due to installation in shallow soils. The adoption of alternative treatment systems, however, is not widespread. Alternative systems are expensive and in many cases require larger surface areas to build and operate. The establishment of a technical advisory committee provided an avenue to approve new and innovative treatment systems that differ from the existing regulations while the countdown towards the proposed new regulations approached. A survey of county health officials in Ohio highlighted the need for training of regulators and delineation of responsibilities to avoid conflicts of interest. Adequate training of regulators will make the regulatory transition a successful venture.

Risk assessment for methylmercury in fish from the Songhua River, China: 30 years after mercury-containing wastewater outfalls were eliminated.

This study aims to investigate the methylmercury contamination of fish from the Songhua River, China. A total of 328 fish representing various trophic levels were captured from ten reaches of the river and determined for methylmercury by gas chromatography method. Total mercury in fish, water and sediments from three typical reaches were analyzed simultaneously. Methylmercury concentrations in fish from the Second Songhua River and the mainstream of the Songhua River were 0.024 ± 0.016 and 0.015 ± 0.007 mg/kg fresh weight, respectively. The proportion of methylmercury to total mercury ranged from 21.8% to 69.7%, with the mean value of 42.6%. The observed methylmercury concentrations were much lower than the historical values and were generally within the reported literature range, and health hazard assessment showed no health risk from exposure to methylmercury by consuming fish from this river, demonstrating that mercury contamination of the Songhua River has been effectively controlled by nearly 30 years of environmental governance and natural purification.

An application of Austrian legal requirements for CSO emissions.

The Austrian standard for designing combined sewer overflow (CSO) detention basins introduces the efficiency of the combined sewer overflows as an indicator for CSO pollution. Additionally criteria for the ambient water quality are defined, which comprehend six kinds of impacts. In this paper, the Austrian legal requirements are described and discussed by means of hydrological modelling. This is exemplified with the case study Innsbruck (Austria) including a description for model building and model calibration. Furthermore an example is shown in order to demonstrate how - in this case- the overall system performance could be improved by implementing a cost-effective rearrangement of the storage tanks already available at the inflow of the wastewater treatment plant. However, this guideline also allows more innovative methods for reducing CSO emissions as measures for better usage of storage volume or de-centralised treatment of stormwater runoff because it is based on a sewer system simulation.

[Socio-economic impact at the household level of the health consequences of toxic waste discharge in Abidjan in 2006]. / Impact socio-économique du déversement de déchets toxiques à Abidjan en 2006 à l'échelle des ménages.

In August 2006, toxic wastes were discharged in the district of Abidjan, causing important health consequences in many households in the area. In order to appreciate the socio-economic impact of the consequences of toxic waste discharge on the households and of the measures taken by the authorities to deal with this catastrophe, and to appreciate the spatial extent of the pollution, we undertook a multidisciplinary transversal investigation at the sites of discharge of oxic waste, from October the 19th to December the 8th, 2006, using a transect sampling methodology. This paper presents the results related to the socio-economic aspects of the survey while the environmental and epidemiological results are presented in two other published papers. The socioeconomics investigation, conducted using a questionnaire, concerned 809 households across the various sites of discharge of toxic waste. More than 62% of households had at least one person who had been affected by toxic waste (affected households). 62.47% of these households were in Cocody district (with 2 sites and 4 points of discharge), 30.14% in Abobo district (with 2 sites and 3 points) and 7.39% in Koumassi district (with 1 site and 1 point). To escape the bad smell and the nuisance, 22.75% of the 501 "affected" households had left their houses. To face the health consequences generated by the toxic waste, 30.54% of the "affected" households engaged expenses. Those were on average of 92 450 FCFA (€141), with a minimum of 1 000 FCFA (€1.5) and a maximum of 1500000 FCFA (€2.287), in spite of the advertisement of the exemption from payment treatment fees made by the government. The decision of destroying cultures and farms near the points of discharge of the toxic products in a radius of 200 meters, taken by the authorities, touched 2.22% of the households. For these households, it did nothing but worsen their state of poverty, since the zone of influence of the toxic waste went well beyond the 200 meters prescribed by the authorities as the limit of the operations of destruction.