Marlborough District Council Roading Assets - Activity Management Plan 2015 - 2018 SECTION 1 EXECUTIVE SUMMARY The road network carries a significant amount of heavy vehicles with approximately 6 million vehicle kilometres travelled by heavy vehicles on the network each year. This high traffic loading is due to the intensive land use throughout much of the region in particular forestry, gravel extraction, aquaculture and vineyard development. Pavements are designed to last 25 years but variations in the traffic loadings can extend or decrease the service life of a pavement significantly. In practice most road pavements will remain in service for between 25 to 50 years. Many of the existing road pavements were constructed prior to the adoption of the current design methods and consequently have been constructed to a lower standard. There is insufficient information on the construction dates of the granular components of the pavements to accurately determine pavement ages. Approximately 75% of the networks pavement history, stored in RAMM, has a default construction date entered into mandatory fields when the actual date is not known. To accurately predict the remaining life of these pavements is not possible as it is highly dependent on the underlying subgrade strength and the nature and location of future development. Life cycle management of pavements is therefore based on condition monitoring rather than age. Roads need to be carefully monitored to ensure that the timing of rehabilitation works is optimised and that a backlog of rehabilitation projects does not build up. Some roads are reaching the end of their service lives and will require rehabilitation in the short to medium term. As these roads reach the end of their lives they will rapidly deteriorate in condition and become increasingly difficult and expensive to maintain. 1.6.1.2.2 6.1.2.2 Surfacing Age Surfacing, with the exception of some short lengths of interlocking concrete block sections in urban areas, are bituminous surfacing of chip seal, asphaltic concrete or slurry seal. A breakdown of the surfacing types is shown in figures 6.1.2.2a and 6.1.2.2b. Urban Pavement Surface Types Figure 6.1.2.2a Rural Pavement Surface Types Figure 6.1.2.2b 30 September 2014 Page 30 of Section 1