The effect of drainage condition on the lifetime of paved roads in Northern Europe

The European Union ROADEX Project 1998 - 2007 is a trans-national roads cooperation aimed at developing ways for interactive and innovative management of low traffic volume roads throughout the Northern Europe. Its goals have been to facilitate research into the common problems in the area. A major problem, shared by all the partners, has been poorly performing drainage. The problem has received general acknowledgement, but data which demonstrates the economic effect of drainage on pavement lifetime has yet to be produced. In this work, which was done as a part of the ROADEX III project, the condition of the drainage of the paved roads of the entire Rovaniemi maintenance area road network was classified. This network in Finnish Lapland presents a road network typical of the Northern part of Europe. The goals for this study were to assess the status of the current drainage condition, compare rutting and roughness values with the drainage condition and, based on these results, calculate the effect of poor drainage on pavement lifetime and annual paving costs. The results of this survey showed that rut development on main roads was 1.52 times faster in sections with the poorest, class 3, drainage than in sections with good quality, class 1, drainage. On local roads with thinner pavement structures the same pavement lifetime ratio was 2.32. Poor drainage had a similar effect on the roughness (IRI) values. The cost benefit calculations showed that, by improving the drainage of paved road networks to a class 1 level, it would be possible to save almost 12 % of the annual paving costs. In terms of the Rovaniemi maintenance area, a network that includes 645 km of paved roads, a savings of approximately 335.000 Euro could be achieved. The results of this analysis demonstrate the economic benefits of investments in improving drainage and maintaining it in good condition. For the covering abstract see ITRD E144473.