Lian Lundy

Integrating sciences to sustain urban ecosystem services

Effective water management within urban settings requires robust multidisciplinary understanding and an appreciation of the value added to urban spaces by providing multifunctional green-blue spaces. Multifunctional landscapes where ecosystem service provisions are ‘designed-in’ can help ‘transition’ cities to more sustainable environments which are more resilient to changing future conditions. With benefits ranging from the supply of water, habitat and energy to pollutant removal, amenity and opportunities for recreation, urban water bodies can provide a focal point for reconnecting humans and nature in otherwise densely built-up areas. Managing water within urban spaces is an essential infrastructure requirement but has historically been undertaken in isolation from other urban functions and spatial requirements. Increasingly, because of the limits of space and need to respond to new drivers (e.g. mitigation of diffuse pollution), more sustainable approaches to urban water management are being applied which can have multiple functions and benefits. This paper presents a review of ecosystem services associated with water, particularly those in urban environments, and uses the emerging language of ecosystem services to provide a framework for discussion. The range of supporting, provisioning, regulating and cultural ecosystem services associated with differing types of urban water bodies are identified. A matrix is then used to evaluate the results of a series of social, ecological and physical science studies co-located on a single stretch of a restored urban river. Findings identify the benefits of, but also barriers to, the implementation of a transdisciplinary research approach. For many, transdisciplinary research still appears to be on the edge of scientific respectability. In order to approach this challenge, it is imperative that we bring together discipline specific expertise to address fundamental and applied problems in a holistic way. The ecosystem services approach offers an exciting mechanism to support researchers in tackling research questions that require thinking beyond traditional scientific boundaries. The opportunity to fully exploit this approach to collaborative working should not be lost.

The sources, impact and management of car park runoff pollution: a review

Traffic emissions contribute significantly to the build-up of diffuse pollution loads on urban surfaces with their subsequent mobilisation and direct discharge posing problems for receiving water quality. This review focuses on the impact and mitigation of solids, metals, nutrients and organic pollutants in the runoff deriving from car parks. Variabilities in the discharged pollutant levels and in the potentials for pollutant mitigation complicate an impact assessment of car park runoff. The different available stormwater best management practices and proprietary devices are reported to be capable of reductions of between 20% and almost 100% for both suspended solids and a range of metals. This review contributes to prioritising the treatment options which can achieve the appropriate pollutant reductions whilst conforming to the site requirements of a typical car park. By applying different treatment scenarios to the runoff from a hypothetical car park, it is shown that optimal performance, in terms of ecological benefits for the receiving water, can be achieved using a treatment train incorporating permeable paving and bioretention systems. The review identifies existing research gaps and emphasises the pertinent management practices as well as design issues which are relevant to the mitigation of car park pollution.

An impact assessment methodology for urban surface runoff quality following best practice treatment.

The paper develops an easy to apply desk-based semi-quantitative approach for the assessment of residual receiving water quality risks associated with urban surface runoff following its conveyance through best practice sustainable drainage systems (SUDS). The innovative procedure utilises an integrated geographical information system (GIS)-based pollution index approach based on surface area impermeability, runoff concentrations/loadings and individual SUDS treatment performance potential to evaluate the level of risk mitigation achievable by SUDS drainage infrastructure. The residual impact is assessed through comparison of the determined pollution index with regulatory receiving water quality standards and objectives. The methodology provides an original theoretically based procedure which complements the current acute risk assessment approaches being widely applied within pluvial flood risk management.

COST Action ES1403: New and Emerging challenges and opportunities in wastewater REUSe (NEREUS)

Treated urban wastewater is currently widely reused to compensate for dwindling water supplies, as it is considered to be a reliable alternative water source. In addition, the increasing demand for food due to the expanding world population, both in respect to food security and food safety, and therefore for irrigation water, renders wastewater reuse a practice of utmost importance. As a consequence, sustainable and safe urban water cycles are presently of high priority on the policy agendas of many countries around the world. Although reuse has a number of benefits and major advances have been made with respect to producing treated effluents for reuse (e.g., successful removal of metals, reduction of chemical oxygen demand and of other pollution parameters), several important questions are still unanswered and barriers exist regarding the safety/sustainability of reuse practice. Knowledge gaps associated with wastewater reuse include the following: (a) possible elemental interactions that may influence the accumulation of metals/elements in the soil and their subsequent uptake by plants and crops, (b) the fateof organic microcontaminants in receiving environments, and (c) the epidemiological potential of antibiotic resistant bacteria and/or resistance genes (ARB&ARG) released in the environment via treated effluent. Possible implications on food-chain contamination (biomagnification) require much attention, since treated wastewater is not exempt of such contaminants. The effluents’ residual organic matter after conventional treatment consists of a number of recalcitrant organic compounds including potential endocrine disrupting compounds, many types of pharmaceuticals including antibiotics, disinfection by-products, personal care products, metabolites and transformation products, other organic substances (i.e. pesticides, surfactants, biocides, etc.), and not to be forgotten ARB&ARG. In fact, preliminary results suggest that the relative abundance of certain ARG or ARB may even be enriched during the wastewater treatment (Rizzo et al. 2013). This leads to their subsequent release in the terrestrial and aquatic environments through disposal and reuse applications, and the level of risk to environmental and human health is yet to be evaluated. Contamination of the environment, food chain, drinking water, etc with ARB&ARG is presently considered to be a serious public health problem. For this reason, the World Health Organization (WHO) (WHO 2013) characterized the development of AR as one of the major global threats to society and recommends intensive monitoring for the identification/surveillance of critical hot spots (e.g., wastewater treatment plants), aiming at reducing its propagation. In September 2014, a national strategy (The White House 2014) was announced in the USA by the White House that lays out a series of steps to address the decreasing effectiveness of antibiotics, many being similar to those identified by WHO. According to the European Centre for Disease Prevention and Control, it is estimated that infections caused by a subset of ARB are responsible for about 25,000 deaths in Europe annually. In addition, the extra healthcare costs and productivity losses due to ARB are estimated to reach EUR 1.5 billion (European Centre for Disease Prevention and Control 2013). In the USA, equally dramatic numbers are reported by the Centers for Disease Control and Prevention, with AR infections killing at least 23,000 people and sickening 2 million each year (The White House 2014). All these issues have not received significant attention in the framework of the wastewater reuse practice. The EUCOST Action ES1403 (NEREUS) aims at consolidating the existing scattered data related to wastewater reuse and will address the open challenges associated with it. It will provide the platform for a systematic consolidation of data and standardization of methods for assessing emerging hazards associated with wastewater reuse. The Action is chaired by D. Fatta-Kassinos from Nireas-International Water Research Center and Department of Civil and Environmental Engineering of the University of Cyprus and vice-chaired by C.Manaia from Escola Superior de Biotecnologia, Universidade Catolica Portugeusa.

Assessing the impact of swales on receiving water quality

Abstract Swales are one type of sustainable drainage system (SuDS) which contribute to the management of water quality in receiving waterbodies. Using a semi-quantitative approach, an impact assessment procedure is applied to the residual water quality that is carried forward to surface waters and groundwaters following treatment within a swale. Both volumetric and pollutant distributions are considered as stormwater passes through the swale system. The pollutant pathways followed by TSS, nitrate, chloride, metals (Cd, Cu, Pb, Zn) and polyaromatic hydrocarbons (PAHs) are determined for a swale receiving highway runoff. For TSS, metals and PAHs between 20% and 29% of the total mean influent pollutant load is predicted to be directed to infiltration through the underlying soils compared to between 4% and 16% of chloride and nitrate. Although surface water impacts are deemed possible, the discharges of swales to groundwaters are assessed to represent a negligible impact for effectively maintained systems.

An impact assessment for urban stormwater use

Stormwater has the potential to provide a non-potable water supply which requires less treatment than municipal wastewaters with the added benefit of reducing pollution and erosion issues in receiving water bodies. However, the adoption of stormwater collection and use as an accepted practice requires that the perceived risks, particularly those associated with public health, are addressed. This paper considers the human health concerns associated with stormwater quality when used for a range of non-potable applications using E. coli, a commonly found pollutant in urban stormwater which is also widely included in human health-based water quality standards and guidelines. Based on a source-pathway-receptor model, scores are allocated, on a scale of 0 to 5, to benchmark increasing the likelihoods of exposure to stormwater during different occupational and non-occupational applications and magnitude of impacts which may result. The impacts are assessed by comparing median stormwater E. coli levels with the reported guideline levels relating to different stormwater uses. Combination of the exposure and impact scores provides an overall risk score for each stormwater application. Low or medium risks are shown to be associated with most stormwater uses except for domestic car washing and occupational irrigation of edible raw food crops where the predicted highest levels of risk posed by median E. coli levels in stormwater necessitate the introduction of remedial actions.

Metal Water-Sediment Interactions and Impacts on an Urban Ecosystem

The EU Water Framework Directive (WFD) requirement that all surface water bodies achieve good ecological status is still a goal for many regulatory authorities in England and Wales. This paper describes field and laboratory studies designed to identify metal contaminant loadings and their distributions within water bodies located in the Lower Lee catchment (London, UK). Water and sediment samples have been collected from increasingly urbanised sites on the River Lee and its main tributaries over a two-year period with samples analysed for total concentrations of cadmium, copper, lead, mercury, nickel, tin, and zinc. Complimentary batch tests indicate a positive relationship between aqueous metal concentrations and the batch test-derived sediment metal release data, particularly during wet weather events. Field data indicate a dynamic relationship between water and sediment concentrations with both being capable of exceeding relevant environmental quality standards/sediment quality guidelines at all sites. Mean sediment metal concentrations across all sites were found to be highest for Cu (141.1 ± 111.0 µg g−1), Pb (175.7 ± 83.0 µg g−1), and Zn (499.9 ± 264.7 µg g−1) with Zn demonstrating elevated mean water concentrations (17.2 ± 13.8 µg L−1) followed by Ni (15.6 ± 11.4 µg L−1) and Cu (11.1 ± 17.8 µg L−1).

Risk management as a basis for integrated water cycle management in Kazakhstan

Abstract Integrated Water Cycle Management (IWCM) aims to bring together a diversity of social, environmental, technological and economic aspects to implement sustainable water and land management systems. This paper investigates the challenges and opportunities facing Kazakhstan as it its efforts to move towards a more sustainable approach to managing its finite and highly stressed water resources. The use of a strategic-level risk governance framework to support a multi-disciplinary Kazakh-EU consortium in working collaboratively towards enhancing capacity and capability to address identified challenges is described. With a clear focus on addressing capacity building needs, a strong emphasis is placed on developing taught integrated water cycle management programmes through communication, stakeholder engagement and policy development including appropriate tools for managing the water issues including hydraulic models, GIS-based systems and scenario developments. Conclusions on the benefits of implementing an EU-style Water Framework Directive for Central Asia based on a risk management approach in Kazakhstan are formulated.