Marlborough District Council Roading Assets - Activity Management Plan 2015 - 2018 SECTION 1 EXECUTIVE SUMMARY Surfacing is designed in accordance with the NZTA’s ‘Bituminous Sealing Manual’ or its replacement publication ‘Chip Sealing NZ’ and is constructed in accordance with the relevant NZTA specifications. There is a reasonable level of confidence in the surfacing age data currently stored in RAMM. The data which includes surfacing dates, surfacing types, expected lives and remaining lives is considered sound and accurate. Figure 6.1.2.2c shows the age of existing surfacings. Seal Age Figure 6.1.2.2c The average age of surfacing on the network is 12.71 years. The average surfacing age provides a snap shot of the status of the surfacing but because there are a range of surfacings on the network with different expected lives, it is more appropriate to consider life expectancy and remaining life of surfacings when looking at the life cycle / forward works programme for surfacing. An analysis of the life expectancy of surfacing on the network, gives an average life expectancy of 13.14 years. Analysis of the ‘remaining life’ of surfacings (life expectancy – age) gives an indication of the likely future annual quantum of resurfacing. When the over age seals (-1 and beyond) are incorporated into the next ten years of the programme the indicative future resurfacing demand in the order of 65 km per year. This quantum relates well with the results of modelling which gives a figure of 72.8km. Figure 6.1.2.2d shows a graph of remaining lives and the indicative future demand. Remaining Surfacing Life Figure 6.1.2.2d The intention is to seal the over age seals in the next 10 years all seals that are over age by more than 1 year have been divided amongst the next 10 sealing years to eliminate the over age surfaces. Over age seal all added together and divided by 10 and added to the next 10 years totals. 1.6.1.3 Current Condition 1.6.1.3.1 Roughness A key indicator of the condition of the existing pavements is ‘ride quality’ measured as a roughness value (NAASRA counts). A full network roughness survey is undertaken on a bi-annual basis. A summary of the latest roughness data (2014) is as follows: 30 September 2014 Page 31 of Section 1