Marlborough District Council Roading Assets - Activity Management Plan 2015 - 2018 SECTION 1 EXECUTIVE SUMMARY Most new subdivisions built in recent years are surfaced in AC, the low noise and aesthetic qualities are preferred by developers as it makes the subdivision more attractive to buyers. The total length of AC surfacing on the network is 51km. Currently 9.2km (59%) of the network with traffic volumes >5000 AADT is surfaced with AC surfacing. A further 2.6km will meet the traffic volume criteria in the next 5 years. In future the threshold is 7500 AADT. Based on expected design lives and increasing demand, relating to increasing traffic volume, the following is the requirement for AC surfacing: Renewal existing AC (AADT >200), 36.6km with design life 25yrs = 1.4km; Renewal existing AC (AADT >7500), 9.2km with design life 10yrs = 0.92km; and New AC site with AADT > 7500, 2.6km over 5 years = 0.5km. On this basis the total length of new AC per year should be approx 2.74km however further analysis of the age of AC surfacing on roads with > 200 AADT shows an average age of 6 years with the oldest around 14 years. Therefore the renewal programme for AC on the lower volume roads will not be required to start until around 2017. The total length of new AC should be in the order of 1.34km per year. The cost of AC is approximately 3 to 4 times that of a chip seal and while it does have a longer design life there would be significant cost implications if a lower minimum traffic volume where used in the strategy. The following is a list of urban roads with greater than 7500 vpd which are not currently AC surfaced which will be resurfaced with AC over the next 5yrs.: Maxwell Rd (RP 630 to 1766); Redwood St (RP 620 to 1647 and 1834 to 2245); Scott St (RP 18 to 181); and Waikawa Rd (RP 675 to 820). Demand for Pavement Strengthening / Rehabilitation due to HCV Increase: some roads within the network deteriorate rapidly if the number of HCV movements increase at significant levels. Forestry and gravel extraction are typical activities which can generate such increases in HCV movements. Market volatility and changes in work programmes within the forestry and gravel industries, makes exact prediction of when and where these increases may occur difficult. Previous AMP’s identified Northbank Road as being particularly vulnerable and recommended a programme of $200 to 300k per annum be spent on rehabilitation for the 10 year period from 2005 to 2015. This programme is now complete. However rehabilitation can be advanced on other roads, based on utilisation of Regional Funding (“R2 fund”). Packages or activities need to be deemed ‘Regionally Significant’ and be economically justified i.e. has a BCR of > 1.0. Roads susceptible to increased HCV movement are: Port Underwood Rd Croisilles – French Pass Rd Kenepuru (602) Waihopai Valley Rd Wakamarina Rd Taylor Pass Rd Kaiuma Bay Rd 1.6.1.6 Life Cycle Management The maintenance of sealed pavements falls into two categories as follows: Reactive Maintenance (Routine Maintenance): reactive works to maintain level of service (e.g. repair of potholes, edge break, crack sealing, etc) Proactive Maintenance (Renewals): inspection and maintenance programmed to prevent asset failure (e.g. Area Wide Treatment, Resealing, etc) This AMP attempts to determine the appropriate mix of Proactive and Reactive maintenance within the Maintenance Contracts to achieve the most cost-effective structure and minimize (optimise) the maintenance costs commensurate with providing realistic and appropriate response times to various activities (e.g. the response times for addressing road icing are very short for safety reasons, whereas occasional weed growth 30 September 2014 Page 38 of Section 1