Contact: K Fuller, ext 7958

1. Summary

1.1 The following decisions are sought:

(i) That there is a further review of the 49 property flooding sites identified by the Environment Agency which have highway implications.

(ii) That £750,000 is set aside from the Government Office for the South East funding for any further studies and works associated with flood alleviation.

(iii) That £243,000 is released for repairs to the highway associated with flood damage.

(iv) That Hambledon Village is treated as a special case and Hampshire County Council supports the Local Drainage Authority in submitting a proposal to the Department for Environment Food and Rural Affairs for funding consideration.

2. Reason

2.1 Flooding mitigation.

3. Other Options Considered and Rejected

3.1 None.

4. Conflicts of Interest Declared by the Decision Maker or a Member or Officer consulted - Not applicable.

5. Dispensation granted by the Standards Committee - Not applicable.

6. Reason(s) for the Matter being dealt with if Urgent - Not applicable.

Approved by: Date:

Councillor K B Estlin

7. Current Flood Risk and Progress on Flood Damage and Flood Alleviation

7.1 Flood Risk - The latest report from the Environment Agency indicates that following a dry start to the winter and average summer rainfall the groundwater and river levels in the county are normal and there is no immediate concern about prolonged groundwater flooding. However, ground water levels are high in certain catchments such as The Candovers and Old Alresford where it is possible that ground water flooding to cellars may occur by the end of the winter. The greatest need currently therefore is to be prepared for any surface water flooding resulting from short duration high rainfall intensity storms.

7.2 Two thousand filled sandbags are being stored as a precautionary measure and Winchester City Council has already provided 1,500 for Hambledon village. Three sandbag filling machines have been strategically placed throughout the county and sandbag stocks have been replenished.

7.3 Flood Warning Arrangements and Policy - A number of measures have been introduced to improve the response and level of information within the County Council and for road users and residents.

(i) Emergency Plans have been updated and Local Authority Flood Policy statements have been completed. This region is the first in the United Kingdom to complete this task.

(ii) Environment Agency Flood Warning arrangements have been updated and are sent directly to this Department and disseminated locally for action. In addition the Environment Agency give regular feedback on the ground water and river levels via e-mail to the Department to assist the weather emergency planning process.

(iii) The weather forecast service has been enhanced to include forecast of rainfall intensity and duration. A web based service is available giving radar imaging of weather fronts and their timing.

(iv) Web Site: a linked website has been developed to cover drainage and flood related matters. This site will be linked to the bulletin board giving users an update on the highway situation.

7.4 Flood Damage Repairs and Flood Alleviation

(i) The network was extensively damaged by the flooding and the Authority, as part of its statutory duty to keep the network in good order, has been carrying out essential repairs. Total funding of £11,250,000 for this work has been found from two sources:

(a) £6,200,000 has been drawn from the Highway Maintenance capital and revenue budget by deferring other planned highway maintenance works; and

(b) £5,050,000 has been granted by the Government Office South East (GOSE) to assist with the repair programme. This funding is available over a two year spend period.

(ii) From the two funding sources £3,280,000 has been spent and earmarked for specific drainage repairs and associated flood alleviation at 160 locations. Good progress has been made on the implementation of these schemes and some 60% has been completed to date.

(iii) Currently £993,000 of the GOSE funding is still to be specifically allocated. This was intentional and it is anticipated that this funding is directed at carriageway repairs on a needs and priority basis. However, in the light of the studies undertaken by the Environment Agency and the mitigation measures identified relating to property flooding alleviation this may need to be reconsidered.

8. Environment Agency Flood Investigation Reports and County Council Studies of Related Highway Flooding

8.1 In March 2001 the Environment Agency commissioned Halcrow Water (Halcrow) to assess the more significant property flooding incidents in Hampshire. The mechanisms of flooding in each case would be analysed, identifying and assessing possible mitigation works wherever these are likely to be feasible. Where mitigation works are considered viable a cost estimate together with a cost benefit assessment have been undertaken in accordance with the rules of the Department for Environment, Food and Rural Affairs (DEFRA). An indication of the responsible owner or authority for further investigation has also been given in each case.

8.2 A cost benefit ratio is also accompanied by a DEFRA score to assign a priority to any identified measures. To qualify for consideration of funding from DEFRA through District Land Drainage Authorities a score above 2 is required. A positive Cost Benefit ratio above 1, whilst not attracting a DEFRA grant, indicates that there is a national benefit in undertaking mitigating measures.

8.3 The studies undertaken by Halcrow were due to be finalised in February 2002; the County Council responded at the draft stage.

8.4 Impact of the Environment Agency (Halcrow) Village Property Flooding Investigation on the Highway Network - The findings of the investigations as they relate to the County Council are itemised in Appendix 1. A summary of the main issues are:

(i) There is a highway related flooding factor in 70 of the 105 studies where highway measures and further investigation may mitigate the impact of any flooding.

(ii) The cost of the identified mitigation measures where the County Council has a responsibility amounts to £1,430,000 (excluding Hambledon Village).

(iii) The Department has already carried out works or has measures planned at 21 locations at a cost of £716,000.

(iv) In the other 49 village locations further investigation or measures are recommended and the estimated cost of these is £714,000.

(v) There are two locations at an estimated cost of £15,000 that exceed the DEFRA cost benefit ratio of 2.

(vi) There are 11 locations at an estimated cost of £267,000 that exceed the DEFRA cost benefit ratio of 1.

(vii) The reports do not clarify adequately the drainage responsibilities, particularly relating to roadside ditches, and there are some factual errors in the reports which have been pointed out. There is also a recommendation to undertake a further review of highway drainage arrangements at many locations.

Environment Agency Reports - Way Forward

8.5 The 49 property flooding locations identified with highway mitigating measures be investigated and reported to the Executive Member.

8.6 At the property flooding locations where mitigation measures have been put forward and the cost benefit is above unity they are evaluated in detail with a view to carrying out work. The outcome of the evaluation will be reported to the Executive Member.

8.7 The investigations be funded from the balance of GOSE funding and a sum of £750,000 be set aside for this and any resulting flood alleviation measures. The remaining funding of £243,000 to be allocated on a needs basis for highway repairs and other related commitments.

8.8 Other Flooding Investigations - Specific reports at the most severely affected locations of highway flooding have been commissioned in partnership with other authorities and these have been passed to the Environment Agency for information. Funding for these investigations and the resulting drainage measures have come from the Highway Maintenance budget.

(i) Twyford Village - Consulting Engineers Upton McGougan have completed a study and recommended replacing sections of the culvert in Finches Lane. The construction works have been completed at a cost of approximately £150,000.

(ii) Farringdon Village - Consulting Engineers Upton McGougan have completed a study and recommended extending the surface water drainage system and increasing its capacity. Works are currently under way with expected completion in the spring 2002. The anticipated cost is £250,000.

(iii) Bramdean Village - Consulting Engineers Upton and McGougan have completed a study and recommended clearance of roadside ditches and culverts. This work is complete at a cost of approximately £50,000. Resurfacing of the A272 is programmed for spring 2002.

(iv) Ropley - Consulting Engineers Giffords have completed a study and recommended that the flood relief causeway is formalised. These works are planned for the spring/summer 2002 at a cost of approximately £200,000.

(v) Hambledon Village - Posford Haskoning were commissioned to investigate the causes of the flooding and identify any measures to alleviate the problem. The consultants have identified a range of options to alleviate and manage the ground water, each of which has been assessed for cost/benefit shown below:

Details of the work to be undertaken under Option F are set out in Appendix 2.

8.9 All of the viable solutions range from £1,000,000 to £3,500,000 to give flooding protection from 1 in 15 to 1 in 200 year return periods. The cost benefit is below unity in all but two of the options considered. The County Council is currently undertaking local road drainage measures proposed in the report at a cost of £120,000. The benefit of more costly mitigation measures must be assessed in the light of the benefit to the community as a whole and any contribution from the County Council as the Highway Authority should be related to the benefit gained by the highway user. It is recognised however that Hambledon is a special situation and has suffered repeatedly over the years from prolonged ground water flooding. In this light it is proposed that scheme option F at a cost of £1,444,607 offering 1 in 100 years protection is promoted by the District Land Drainage Authority to DEFRA as a special case for funding consideration.

9. Flood Steering Group

9.1 The County Council set up a Flood Steering Group at the height of the flooding to include all responsible bodies, such as the Environment Agency, local authorities, the Water Companies and the Association of Parish Councils. The aim and objective of the group is to assign roles and responsibilities relating to flooding, review and identify flood risks and consider and prioritise flooding solutions. The Steering Group is led by the Environment Agency.

9.2 The Steering Group has been successful in achieving a focus on flooding issues and has:

(i) organised two conferences which set out the issues, the organisations involved and the way forward with opportunities for community representatives to ask questions;

(ii) coordinated the investigations undertaken by various consultants at over 100 locations and shared preliminary results of the investigations;

(iii) updated emergency plans and identified and shared information on sand bag stocks;

(iv) agreed responsibility of Southern Water to carry out CCTV investigations of sewers where flooding has occurred as a result of ground water infiltration. Southern Water is looking to seal significant leaks on its sewers;

(v) agreed a protocol for emergency discharge points in flooding situations;

(vi) agreed to produce best practice guidance on flooding issues, building on the experience of the parish councils; circulated free public information leaflets and looking to expand this further; and

(vii) completed the Flood Policy Statements, the only region in the country to fulfil this requirement.

9.3 There are issues that the group consider should be addressed at a national level, these include:

(i) a review of design standards relating to sewer systems and flood risk; and

(ii) a review of the protection of sewer systems from water infiltration and inundation, associated funding issues and prioritisation by OFWAT.

10. Drainage Records

10.1 The flooding events highlighted the need for good and up to date highway drainage records and the County Council is looking to develop and enhance the current records utilising the computerised geographical data base. A significant additional amount of data collection is required and a partnership entered into with other organisations such as the water authorities and parish councils to gather information.

10.2 The County Council has already embarked on a programme of collecting and updating drainage records. A full inventory of gully positions and cleansing details will be completed and available on the computerised geographical system by the end of 2002. Resource and funding of £25,000 each year for the next three years will be required however to fully develop the data base. This funding may be found from the special studies budget.

11. Highways Drainage Maintenance Policy

11.1 The County Council's policy relating to drainage is included within the Highway Maintenance Management Plan which was updated in August 2000. The policy accords well with the most recently published national standards contained within the Code of Practice `Delivering Best Value in Highway Maintenance' published in July 2001.

11.2 The existing inspection arrangement of piped drainage systems, including culverts, aligns with best practice but needs to be formalised against a set inspection frequency and cycle. It is proposed that these items are visually inspected from the inlet and outlet positions as a minimum, annually. Further to this, increased inspection is recommended where localised flooding problems are known to exist.

11.3 The maintenance arrangements for drainage features, such as gullies and soakaways, meet national standards of a minimum of one cleanse per annum for gullies. Gullies which are prone to flooding are cleansed at a greater frequency. However as part of the new Term Maintenance Contract the cleansing regime is based on a performance requirement which will direct efforts to those drainage items most in need of cleansing. The maintenance need of piped systems is led by identified problems that manifest themselves as a result of the routine gully cleansing programme, inspections or localised flooding. This process works well. Regular inspection of culverts and piped systems however is likely to lead to increased maintenance work, particularly clearance of silt and debris, and account for this will need to be made in the highway maintenance budget.

11.4 The estimated impact of this adjustment is 0.5 FTEs staff time £15,000 and works in the order of £50,000 each year. This resource and funding is expected to be found from within the existing establishment and highway maintenance budget.

12. Role of the Land Drainage Authority

12.1 The local authorities currently exercise the role of the Land Drainage Authority. The Land Drainage Act 1991 confers powers on local authorities which relate to flood prevention and maintaining flows in watercourses. These powers are permissive, giving the authority discretion over their use. All of the local authorities in Hampshire have prepared Flood Policy Statements and will carry out inspections of watercourse defences that have been identified as a flooding risk (critical watercourses).

12.2 The Department is represented on a Hampshire Land Drainage Group which meets on a regular basis to ensure a consistent and coordinated approach in the region.

12.3 It is apparent however that each local authority has a different resource and priority of fulfilling the land drainage role and there is wide variation in the service throughout the county. This was demonstrated during the winter flooding of 2000/01 when, due to the lack of resource, staff were more rapidly overwhelmed by events. Straightforward arrangements, such as the provision of sandbags and response, were difficult to mobilise in some parts of Hampshire and suffered with confused communications, especially to the public. In some areas the partnership between the County Council and the local authority worked well and has become a model in the revised procedure.

12.4 The County Council, because of its size and automatic involvement in flooding related problems, has necessarily taken a high profile role during the flooding crisis which has continued whilst remedial measures are in hand. A number of jointly commissioned reports have been undertaken with the drainage authorities. The budget spent by the County Council far exceeds the total spent by the Land Drainage Authority on fluvial, non DEFRA grant aided schemes. The public are therefore increasingly looking to the County Council to be involved in all flooding and drainage matters. The County Council does have permissive drainage powers in the same way as local authorities and can therefore exercise a `local drainage authority' role.

12.5 There may be benefit in reviewing the role of the County Council relating to its drainage responsibilities to assess if a land drainage role may be more effectively delivered through the County Council. The support of the local authorities will be needed prior to embarking on such a sensitive exercise.

13. Conclusions

13.1 There is a reduced likelihood of prolonged ground water flooding and the main risk is surface water flooding due to short duration, high intensity storms. Lessons have been learnt from the serious long term flooding over the winter of 2000/01 and improved emergency plans are in place to warn and respond to flooding emergencies.

13.2 To date £11,250,000 has been spent/earmarked from Highway Maintenance and GOSE funding for remedial measures to damaged roads and bridges, drainage repairs and flood alleviation.

13.3 The Environment Agency has investigated 105 village locations which suffered from property flooding and highways measures, 21 (30%) of these have already been undertaken. A review of the highway drainage and mitigation measures are recommended by the Environment Agency in 49 villages. The estimated cost of this work is £714,00 however this figure is reduced to £267,000 for those locations with a cost benefit of 1 and £15,000 with a cost benefit of 2. These figures exclude Hambledon village flooding which is the subject of a separate study.

13.4 The investigation into Hambledon village by Posford Haskoning puts forward a number of flood alleviation options. In view of the repeated and prolonged flooding it is being proposed as a special case for submission by the local authority to DEFRA for funding consideration. The County Council may also contribute funding commensurate with the highway flooding disbenefit.

13.5 There is a strong business case to collect and record drainage information and hold the data in a consistent way, preferably in a GIS format. Resources of £25,000 per annum for the next three years is required to support this initiative.

13.6 The current highway drainage maintenance policy accords well with national standards. There is a need to improve the inspection arrangements associated with culverts. The resource impact of this is 0.5 FTEs which is anticipated to be absorbed within the existing staffing structure, however it is anticipated that additional drainage maintenance of £50,000 per annum will result and this needs to be reflected in the Highway Maintenance budget.

13.7 There is a case to review the land drainage management throughout Hampshire to achieve a consistent service county-wide.

7018/KFr

APPENDIX 1

ENVIRONMENT AGENCY FLOODING VILLAGE REPORTS (HALCROW STUDY)

APPENDIX 2

HAMBLEDON VILLAGE FLOODING

OPTION F

Posford Haskoning Consultant Engineers commissioned jointly by Hampshire County Council and Winchester City Council have investigated the causes of the flooding events and possible mitigation measures. They have put forward a range of options to offer flood protection and option `F' offers protection up to a 1 in 100 year return against flooding with a cost benefit above unity. From the Posford Haskoning study it is the only realistic option available to give such a level of protection and is therefore the option the County Council could support.

Option `F'- New Highway and Flood Water Drainage `Open' Drainage Channels

Estimated cost £1,444,607

This solution is similar to the historic open ditches which existed in the village along the roadside until the Second World War. Reinstatement of the original `great ditch' is not practical due to the restraints of land, roadway and access to adjoining premises. A smaller drainage ditch which has the same function and principles as the `great ditch' but taking advantage of the hydraulic efficiencies of a pre-formed channel is proposed. This option will satisfactorily deal with the volumes of water experienced in the winter of 2000/01. It will also be necessary to carry out localised regrading of the downstream ditch to provide the required invert levels.

This option will require the excavation of the road and footpath edges through the village and accommodate the vehicular and pedestrian traffic using the route. The recommended option will need to be carefully considered from an environmental perspective and the implications of the scheme in terms of effect on properties, street scene and character of the conservation area.