Effects of weather conditions on drinking water distribution pipe failures in the Netherlands

Abstract

The influence of the weather parameters of temperature, wind and drought on pipe failure of drinking water distribution pipes was studied for the Netherlands. Several data sources were used relating weather effects to pipe failure: pipe failure data, regional weather data from different weather stations in the Netherlands, soil settlement data obtained from satellites and (modelled) pressure data. For asbestos-cement (AC) and cast iron (CI) pipes, temperature was an important factor. CI pipes showed increased pipe failures at low temperatures, which confirms results from previous studies, whereas AC pipes showed increased pipe failures at high temperatures. Pipe failure rates were higher for pipes that on average received higher internal pressures. This study also showed that wind resulted in additional pipe failures caused by uprooting of trees during a severe storm. With respect to drought, in some regions in the Netherlands, increased pipe failures during periods of drought were found. A small influence of soil settlement on pipe failure was found using remote-sensing techniques for a small area (5 × 10 km) in the Netherlands.

Using generalized additive models to investigate the environmental effects on pipe failure in clean water networks

“…Cooling of soils is also exacerbated by the presence of water and therefore, has more effect on soils with high water retention capacity. This is reflected in these data where the highest number of pipe failures for iron is observed in clay and peat soils, in line with previous studies 8 . Peat and clay soils typically retain more moisture after rainfall due to small pores and a slow permeability of <0.1 m day −1 .…”

“…This is due to the effects of ground movement of highly expandable clay soils, as a result of associated clay minerals (i.e. smectite, montmorillonite and vermiculite) 23 which are highly responsive to soil water content 24 ; similar to findings in the Netherlands and Australia 7,8 . A high number of AC pipe failures is especially seen in alluvial clay and peat soils that have a high shrink swell potential of 12-15% volumetric expansion or greater if drained to a 2 m depth.…”

“…In interpreting the results, iron pipe failures increase during winter when the temperature is cold, being particularly vulnerable to temperatures below 3°C. This is attributed to the effects of air frost, and the subsequent cooling of soils adding additional stress on pipes 8,9,19 . Cooling of soils is also exacerbated by the presence of water and therefore, has more effect on soils with high water retention capacity.…”

“…In the last two decades, UK water companies have increased the quantity and quality of network data, enabling a wider range of data correlated with pipe failure to be considered when building statistical models. An understanding of how each variable influences pipe failure is important and recent studies have provided useful insights, exploring environmental effects on pipes [6][7][8][9][10] .…”

“…The literature has reported a correlation between seasonal variation and pipe failures, as a consequence of changing weather (temperature, frost and rainfall deficit (RD)) and soil conditions (pH, ground hazards such as shrink swell, texture, moisture content) [6][7][8]11,12 . Failures during the winter are typically found in iron and to a lesser extent steel and ductile iron (SDI) pipes, and are associated with cold temperatures (typically below 3°C), internal water temperature, rapid temperature transit and prolonged periods of frost 8,9,13 . During the summer a higher number of pipe failures are typically found in asbestos cement (AC) and polyvinyl chloride (PVC) pipes 6,7 and are associated with temperature and high RD which results in ground movement from soil shrink swell, associated with clay soils.…”