Urbanisation

In order to meet these challenges, UNESCO-IHE is developing solutions based on several key concepts of urban water management including: resilience of urban water systems to global change pressures; interventions over the entire urban water cycle; reconsideration of the way water is used (and reused); greater application of natural systems for water and wastewater treatment; governance and financial management structures, covering the entire urban water cycle.

Our research aims to provide solutions for sustainable urban water management by considering the urban water cycle (UWC) in an integrated manner.

Focus areas:

• Delivering a blueprint for integrated urban water management
• Recognizing risks and uncertainty in urban water management
• Developing treatment processes based on natural systems
• Developing low-cost decentralized water supply and sanitation systems
• Developing technologies for advanced water and wastewater treatment
• Urban flood risk

Core groups involved:

• Water supply and sanitation (UWS Department)
• Sustainable urban infrastructure systems (UWS Department)
• Water services management (MAI Department)
• Pollution prevention and control (ER Department)
• Hydraulic engineering (WE Department)

Focus Areas:

Delivering a blueprint for integrated urban water management

An integrated urban water management approach involves managing freshwater, wastewater, and storm water as links within the resource management structure, using an urban area as the unit of management.

Currently we are developing an integrated modelling approach that will enable a full understanding of the implications of these concepts across the entire urban water cycle, while allowing optimal designs to be generated. These integrated urban water models will be driven by sustainability indicators, and will recognize inherent uncertainties.

Recognising risks and uncertainty in urban water management

The result of global change could pose increased threats to cities; including water supply shortages, increased risk of flooding, pollution by combined sewer sewers and contamination by treated or untreated wastewater. Good decisions and research must address uncertainty and variability associated with global changes.

Currently we are developing frameworks for establishing risk indicators that can be used for an integrated assessment of the risks associated with urban water systems. The indicators will be used in a quantitative way (using physical models; fact generators) and a qualitative way (using management models and decision support systems; judgment generators).

Developing treatment processes based on natural systems

Natural treatment systems, for drinking water production and wastewater disposal/reuse, are attractive because of their low cost, sustainability, and relevance to developing countries. We are currently investigating the potential of river or lake bank filtration (BF) systems for drinking water treatment process.

BF is a multi-objective treatment process, providing removal of turbidity, NOM, organic micropollutants, microorganisms and nitrogen. We also investigating the potential of soil aquifer treatment (SAT) as a natural and sustainable wastewater treatment process. SAT is a multi-objective treatment process, providing removal of solids, EfOM, organic micropollutants, microorganisms and nitrogen.

Developing low-cost decentralized water supply and sanitation

In response to the situation regarding poor groundwater quality in several developing countries, UNESCO-IHE developed the award wining simple and affordable ‘family filter’ for treatment of arsenic and iron containing groundwater. We are planning to further develop this technology and test it more extensively internationally.

Another emerging research area is ecological sanitation where our focus is on: urine-diversion dehydrating toilets with downstream processing and reuse, and; options to improve faecal sludge management, to enable safe reuse and energy recovery via decentralized biogas plants.

Developing technologies for advanced treatment

Both conventional drinking water and wastewater treatment have difficulties in meeting the increasing and more stringent water quality objectives. Hence we are currently researching 4 areas to tackle this problem:

1. membranes (membrane filtration for drinking water production, membrane desalination, membrane bioreactors in sewage and industrial effluent treatment, and wastewater reclamation and/or reuse);
2. adsorbents (targeting inorganic micropollutants such as arsenic and chromium);
3. characterisation and removal of natural organic matter (NOM), and;
4. advanced nutrient removal from wastewater including aspects of biological process fundamentals and activated sludge population dynamics.

Urban flood risk

Due to the high density of population and infrastructure in urban areas, the risk of damage from flooding is high. Research at UNESCO-IHE is developing models of how we can predict flood risk in urban areas for both planning and real-time emergency management.

These models required innovative approaches to address the differing length scales and must harness the latest developments in remote sensing.