Går det att generera ett hjälpmedel för att dimensionera vägtrummor?

Abstract: Every year the Swedish infrastructure is afflicted with more or less severe damages caused by water. The damages are often caused by flooding due to underdimensioned culverts. The fact that an operational infrastructure is needed to maintain a financial and ecological profitable forestry shows the benefit of a less frequency of underdimensioned culverts. The purpose of the study was to investigate in which proportion the inventoried culverts and road bridges are underdimensioned. Hopefully the study can be used as a new tool for the dimensioning of water passages to decrease the frequency of underdimensioned culverts. The study covers 5 940 culverts and 160 road bridges in five drainage areas located in Gävleborgs County, Sweden. Thanks to the unique inventory of culverts and road bridges made by Skogsstyrelsen, the study has been possible to perform. The inventory recorded high-resolution coordinates of the culverts and some geometrical information, such as diameter and length. That data combined with the new digital elevation and runoff-information from SMHI has been used to perform the calculations. Two different water flows has been used, called monthly average run-off and high-flow. The result showed that barely five percent of all the culverts are underdimensioned by the monthly average run-off and just over five percent by high-flow. The fact that the water flow increases several times during high-flow does not show a remarkable impact on the frequency of underdimensioned culverts. Even though, the underdimensioned culverts could cause extensive damage on the infrastructure and to the living organisms which is living in the water.