I. N. Vloerbergh’s research while affiliated with KWR Water Research Institute and other places

Failure data are a valuable source of information on the condition of underground assets. Systematic registration of relevant items on cause, nature and circumstances of each occurring failure is, however, complicated in day-to-day practice. Moreover, in a network of limited size it takes a long time to obtain a statistically relevant amount of data. Dutch water companies in collaboration with the KWR Watercycle Research Institute have joined forces and developed a data standard and central database to store and analyse failure data. As of early 2012, 66,000 km of network are monitored, providing around 2,500 records on failure annually. All in all it provides solid information needed for strategic asset management that helps to support well established asset management plans.

In het kader van bedrijfstakonderzoek Client21 voerde KWR Watercycle Research Institute met collega-instituten in het Europese onderzoeksproject TECHNEAU een studie uit naar klantwensen en bedrijfsprestaties. Met medewerkers van de Wageningen Universiteit zijn ontwikkelingen in de gedragspraktijk van waterverbruik in kaart gebracht. Hieruit blijkt dat de Nederlandse drinkwaterconsument over het algemeen tevreden is en het liefst alles wil houden zoals het is. Hij of zij wenst zich niet druk te hoeven maken over drinkwater. Het moet schoon, veilig en altijd voorhanden zijn, tegen een redelijke prijs. Hoewel in de sector het idee leeft dat het verstrekken van informatie het vertrouwen van consumenten vergroot, blijkt de gemiddelde consument weinig behoefte te hebben aan huis-aan-huis verspreide informatie over drinkwaterzaken. Verder blijken de gedragspraktijken rond watergebruik te veranderen. Consumenten zien water steeds meer als onderdeel van hun behoefte aan een goede gezondheid, wellness of comfort. Drinkwaterbedrijven kunnen hun dienstverlening verbeteren door hierop in te spelen. Consumenten vinden innovaties en nieuwe rollen bij het drinkwaterbedrijf passen, zolang deze op één of andere manier te maken hebben met waterkwaliteit en milieu (verantwoord gebruik).

In collaboration with Kiwa Water Research, TNO (Netherlands Organisation for Applied Scientific Research) has investigated the possibilities to detect and classify aberrant sounds in water networks, using acoustic sensors. Amongst the sources of such sounds are pumps, drills, mechanical impacts, which could indicate, for instance, a terrorist's attempt to inject a toxicant into the water mains. In parallel, an important spin-off is recognised in the detection of other sounds, such as those caused by leaks in water pipes and leaking valves. The acoustic water pipe monitoring project was carried out between 2003 and 2007 in three distinct phases: • The first phase was carried out in 2003-2004 to gain knowledge on the subject. Models were developed for the sound propagation in water pipes and computer simulations were carried out to specify detection ranges. • In the second phase, in 2005-2006, the knowledge created in phase 1 was applied for detection of leakage and terrorist attacks. To this end, a number of field experiments were carried out to characterise background noise and suspicious sounds. It was shown that both leakage and intrusion sounds could be detected up to a range of 100 m in regular 110-mm diameter PVC pipes. At this point, Kiwa Water Research and TNO decided to focus their efforts on terrorist detection in the third and last phase of the project. • In the third phase, carried out in 2006-2007, a demonstrator was developed for the detection and classification of aberrant sounds and tested on an operational water supply system. Overall, the TNO acoustic monitoring demonstrator, equipped with two sensors fixed on fire hydrants and two on service taps, has proven to be a suitable and promising system for protection of buildings: it is capable of working in real time and detected about 90% of terrorist intrusion sounds within a range of 110 m (a range suitable for building protection). Using the techniques developed for leakage detection in phase 2, and a similar acoustic demonstrator, the performance of operational systems could further be assessed to detect leakage.