IWW Water Centre

Research Highlights in 2012 and 2013

Diminishing nitrate reduction capacity in aquifers – ­prognosis and assessment

The Institute has developed practical methods, prognostic models and evaluation processes to quantify existing nitrate reduction capacity, thus making it possible to forecast the development of nitrate levels in raw water.

New flushing method developed for large-diameter pipes

There has been no efficient flushing method available to date for large-diameter drinking water pipes (e.g. transport or long-distance water pipes >DN 400). The common methods, such as flushing with clear water front or pigging, have often been associated with poor cleaning performance, intensive preparation or high risk. Based on experi­mental studies and the latest modelling, the IWW has been able to develop a combined method of impulse flushing and innovative pigging with liquid ice (“ice pigging”) as one of several practicable and efficient solutions.

Ozonation and activated carbon for micropollutant ­removal 

Ozonation and activated carbon filtration are the state of the art when it comes to technology to remove organic microcontaminants. Conventional installation and operation of ozone plants in drinking water purification impose tight limits on the dosage and delivery of ozone. At the IWW, a method was developed to optimise ozone delivery and control dosage in relation to the untreated water. This development unlocks a great deal of potential for optimising the performance, energy efficiency and cost effectiveness of existing ozone plants.

A priority shared by several of the projects within the “NRW Water Masterplan” (www.masterplan-wasser.nrw.de) has been to develop adsorption procedures with activated carbon as
a further stage of wastewater purification, with the aim of reducing emissions from pharmaceuticals, x-ray diagnostic agents, industrial chemicals and pesticides into the environment. In the spring of 2013, Johannes Remmel, Minister for Climate Protection, Environment, Agriculture, Nature Conservation and Consumer Protection of the German State of North Rhine-Westphalia (MKULNV NRW), inaugurated the first large-scale filters for routine operation at a sewage works.

How sustainable is the urban water cycle?

Attention has been drawn both politically and socially to the need for sustainability as a principle of long-term responsible resource use and management, also in the water sector. As part of the EU research project TRUST (www.trust-i.net), coordinated by the IWW with 30 partners from 11 countries, a definition of sustainability and an evaluation system were ­developed specifically for the water sector and implemented in a sustainability self-assessment web tool. TRUST is made up of 10 major European water suppliers and wastewater disposal companies (Hamburg, Oslo, Amsterdam, Madrid, Athens, Bucharest, ­Algarve, Scottish Water, Reggio ­Emilia, Schiphol), who are testing this and other ­instruments developed by the IWW, including a roadmapping guideline for strategic development towards sustainable urban water management.

Drinking water networks: pure drinking water at rising temperatures

Climate change can cause the temperature in the top layers of the earth’s surface to rise, which in turn affects the temperature of drinking water in the distribution network. Appropriate measures to safeguard against the resulting increased risk of bacterial contamination are being developed as part of a BMBF-funded project called “dynaklim”. It sets out to ensure low nutrient levels in drinking water, where necessary by means of multi-stage processing, the use of low-nutrient seals and pipes, and to minimise stagnation phases in the supply of drinking water.

The Ruhr: supplying bathing and drinking water to a conurbation

The Ruhr serves a local recreational region incorporating close on 5 million people and supplies drinking water to the Ruhr conurbation.
In spite of microbiological risks, the Ruhr is also used for swimming, although this is banned in large sections of the river. The IWW coordinates the BMBF project (www.sichere-ruhr.de) that is developing a comprehensive concept for risk management to ensure the Ruhr’s water quality for drinking and intermittent use for bathing. Examples of the work being conducted in the project include developing a model-assisted prognosis and early-warning system to impose or lift swimming restrictions on a situational basis. The participation of the population and other stakeholders plays a key role here.