Claim for Emergency Capital Funding Exceptional Damage to Norfolk County Council’S Highways in the ‘Fens’ March 2012
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Claim for Emergency Capital Funding Exceptional Damage to Norfolk County Council’s Highways in the ‘Fens’ March 2012 Norfolk County Council 1 Contents Page Executive Summary 3 1 Introduction 4 1.1 Background 4 1.2 Physical Parameters 6 1.3 Other Funding Possibilities 6 2 Analysis 7 2.1 Outline 7 2.2 Network level Summary 7 2.3 ‘A’ Roads 7 2.4 ‘B’ Roads 10 2.5 ‘C’ Roads 12 2.6 ‘U’ Roads 13 2.7 Identified drought damage schemes – Group Analysis 15 2.8 Identified drought damage schemes – Individual Analysis 16 3 Options considered 17 4 Officer Contact Information 17 Appendices A. Plan showing drought damage scheme proposals on geological background B. A summary sheet detailing all of the drought damage scheme proposals C. Details of each individual scheme proposal 2 Executive Summary 1. Background 1.1. This region of England has experienced a period of significant drought. 1.2. The Fenland area predominantly has of sub-soils containing substantial quantities of peat and other water susceptible sub-strata. The lowering of the water table results in shrinkage off these susceptible soils causing significant drought damage to the road network in the form of differential settlement and cracking. These defects represent safety hazards and are causing local concern. 1.3. The five local authorities in the area have agreed a traffic sign protocol to produce a consistent approach for the road damage in Fenland. In some severe circumstances this may include road closure which would impose a burden on the economic activity in the locality. 2. Claim for additional capital funding 2.1. Our network analysis of condition data in Norfolk County Council’s Fen area has shown deterioration in condition that amounts to £8.92 million. If a betterment deduction of 40% for previous fair condition this would still amount to £5.35 million. 2.2. We have so far identified 45 drought damage related schemes totalling £3.8million and this is likely to increase. 2.3. We are making a request for additional emergency capital funding of £3.8million for the full cost of the identified drought damage related schemes. 3 1 Introduction 1.1 Background 1.1.1 This region of England is continuing to experience a period of extreme drought. Information from the Environment Agency indicates: “Lincolnshire, Cambridgeshire, parts of Bedfordshire and Northamptonshire, and west Norfolk are still in drought because the water resources situation (especially groundwater) has not improved” 1.1.2 The Map from the Environment Agency below, details the situation in June 2011. 1.1.3 4 1.1.4 As a result of the drought, the ground water levels are falling and the moisture content in our road formation is changing. The consequence of this is exceptional damage to all categories of roads in the Fens. This is predominantly because of sub-soils containing substantial quantities of peat and other water susceptible sub-strata. The extent of this in western Norfolk is detailed in the following map. 1.1.5 1.1.6 On many roads, including principal roads, the damage is resulting in safety hazards including: o Increased deterioration of the longitudinal profile of roads requiring drivers to reduce speeds below those that would normally be appropriate for the width and alignment of the roads to minimise the risk of vehicles leaving the roads. o Severe localised transverse depressions which require drivers to slow to speeds below 20mph. o Longitudinal differential settlement and cracking requiring the provision of supplementary road signs to warn drivers and enable the road to remain open. 5 1.2 Physical Parameters 1.2.1 The following table indicates the length of the Fen Roads in relation to our total network km. 1.2.2 Classification Total Length kms Fen Length Fen Length % kms ‘A’ Roads 769.43 106 14% ‘B’ Roads 644.57 39 6% ‘C’ Roads 3418.94 308 9% ‘U’ Roads 4406.55 364 8% ‘U’ Roads (unmade) 498.42 115 23% Back Lanes (V) 26.71 0 0% Total 9764.62 932 10% 1.3 Other Funding Possibilities 1.3.1 In Norfolk we have developed our asset management practices and these have indicated that we need between £30m and £35m to maintain our highway assets at their current condition. The allocation from the Department for Transport for 2012/13 is £21.403m, well short of our need. 1.3.2 In view of the importance we place on maintaining our assets we have used the funding flexibility to transfer all but £2.1m of the integrated transport funding to maintenance, and added £3.5m of our own resources. The resulting budget of £28.9m is still short of that required. Given the level of under-funding it is not practical for us to hold a contingency for extraordinary events. 1.3.3 We do of course have the flexibility to deal with less widespread or single site issues by varying our programme and deferring planned schemes. However, this drought-related damage affects such a significant proportion of our network (10%) that diverting resources from the planned programme would delay other essential schemes, leading to further deterioration, escalating costs and a growing maintenance backlog. 1.3.4 Our network analysis of condition data in Norfolk County Council’s Fen area has shown deterioration in condition that amounts to £8.92 million. If a betterment deduction of 40% for previous fair condition this would still amount to £5.35 million. 1.3.5 We have so far identified 45 drought damage related schemes totalling £3.8 million and this is likely to increase. 1.3.6 We are making a request for additional emergency capital funding of £3.8 million for the full cost of the identified drought damage related schemes. 6 2 Analysis 2.1 Outline 2.1.1 We have put together an analysis which details increased deterioration in the Fens as a consequence of the drought. This is at three levels;- • Network per class • Identified ‘damage’ schemes - On a group basis • Identified ‘damage’ schemes - Individual site details 2.2 Network level Summary 2.2.1 By analysing condition survey data sets we have determined the extent of change in the Fen Roads compared with the whole network. 2.2.2 We have established the works cost of the drought damage caused by;- • Measuring ukpms defects • Applied our appropriate treatment response • Applied our typical scheme efficiency in targeting these defects as shown in the following table;- Classification Cost of additional works damage in millions ‘A’ Roads £1.33 ‘B’ Roads £1.08 ‘C’ Roads £0.71 ‘U’ Roads £4.81 Total £7.93 2.2.2.1 The average fee cost for our surfacing schemes is currently 12.5%. When applied to the cost of the works this gives an overall cost to the authority for drought damage so far as;- Total Cost of additional damage in millions Works & fees £8.92 2.2.2.2 The evidence for each road class follows. 2.3 ‘A’ Roads Fen analysis 2.3.1 We utilise annual ‘SCANNER’ surveys on our ‘A’ road to comply with the requirements of the single data set, of whole of government accounts and our asset management requirements. 2.3.2 We undertake these surveys annual during September and October which is after the summer season of surface dressing. 2.3.3 We have aligned the defect to treatments utilised in Norfolk, our price schedule and typical treatment efficiencies in order to present the actual estimated costs for the works required. 7 2.3.4 We have separated out our ‘A’ Fen roads as a dataset so we can compare the impact of the drought to here in comparison with the remainder of Non- Fen ‘A’ roads as a control. 2.3.5 This network analysis shows ‘A’ fen roads deteriorating as follows;- 2010/11 £3.99 million 2011/12 £5.32 million Deterioration £1.33 million 2.3.6 This is the cost of treating defects, with our appropriate treatments and typical scheme efficiency. 2.3.7 Assumptions • Costs o Surface dressing - £5.43/m² o Plane and inlay 40mm - £24.77/m² o Plane and inlay 100mm - £45.70/m² o These all include some element of soft spot repair or pre- dressing patching • Efficiency o Rate of defects removed per scheme of 53%. 2.3.8 We have carried out a detailed analysis of the defect types in the Fen and Non-Fen ‘A’ roads. 2.3.9 Our analysis has identified that Norfolk’s Fen ‘A’ roads as having a markedly higher percentage of defective carriageway than our Non-Fen ‘A’ network. 2.3.10 SCANNER survey results of “Plan work” (at the top of the Scanner defective threshold/Red) or “investigate work” (defective along the Scanner scale/Amber) categories are as shown in the following table. A roads Red Amber Total 2011 Fen 5.6% 26.7% 32.3% 2011 Non-Fen 3.4% 22.2% 25.6% 2.3.11 The following graph shows equivalent year RCI percentage for Red. In line with the rules and parameters the RCI is aggregated over 2-years representing 100% of the network in both directions. Here we can see, by the gradient of the graph that the Fen area has deteriorated at a higher rate per year than the Non-Fen network. This is despite efforts to target schemes in the Fen area due to recognised structural issues :- 8 2.3.12 2.3.13 The higher Fen NI appears to have been triggered by a larger proportion of structural defects, • Longitudinal variance, both at 3m and 10m, have increased considerably in the Fen area where over the same period this has fallen elsewhere is the County - again this leads us to conclude that the variable soils have different magnitudes of susceptibility to drying • Left rut also having a significantly larger portion in the Fens rising by 28% in quantity in the year from 2010 to 2011 - again this leads us to conclude that the road edges are more susceptible to drying • Cracking also increased by a significant length - due to rapid drying of the underlying soils, consequently we have had excess cracking that will rapidly lead to structural defects if not addressed 2.3.14 The following graph shows the actual quantity, in metres, of the four chosen defects and the gradient shows the speed with which the deterioration is developing.