Northumbrian Water Ouseburn Flooding - Brunton Park Meeting 17th January 2006

Introductions Les Hall – Investment Delivery Team Leader

Presentation Topics: - Flooding 2005 – An Overview Progress to Date Key Findings The cause of flooding on 30 th June 2005 Growth Future Plans Timescales

Sewer flooding – significant events 2005 – significant sewer flooding events Contact numbers 14/15/16/17 April June June August August764 9 September275 12/13 October October232

Sewer flooding – monthly contact

Sewer flooding – daily call volumes

DG7 operational contact breakdown 2004/ /06

Acomb Crescent, Fawdon - Progress to date – Operations CCTV of 3 km Sewer Cleansing almost complete (3 km) Flap valve installed on Surface Water Sewer New Grill and safety railings installed on Overflow CSO chamber de-silted as part of regular maintenance programme

Acomb Crescent, Fawdon - Progress to date – Investigation Independent consultant appointed - Entec Entec have visited site and spoken to some residents to understand flood mechanisms and establish all areas affected Hydraulic model revisited and updated Details of 30 th June fed into the model Model predicts flooding in the areas where actually experienced

Key Findings – Ouseburn A1 Western Bypass & Retail Park discharge to Ouseburn u/s of Redhouse Farm Estate Intense rainfall causes Ouseburn to react quickly Ouseburn re-profiled by EA since 2000 Ouseburn levels can be higher than weir level in the Combined Sewer Overflow

Key Findings – Initial Investigation Rainfall data not available for 30/6/05 – unable to attribute a return frequency for this ‘extreme’ very localised event Hydraulic model predicts incapacity at 1 in 10 year event and flooding could occur without the influence of the Ouseburn River levels are however a significant factor in terms of frequency and severity of flooding Had river level been that of 2000 flooding in 2005 would have been much worse Siltation of continuation pipes and mechanical screen have a small effect of spill volume

The Cause(s) of Flooding ‘Extreme’ very localised rainfall event (30/6/05) Incapacity in part of the Combined Sewer network Levels of the Ouseburn Topography and relative position/level of properties to the Ouseburn Invert of Sewer49.76m AOD Low spot (65-77 Acomb) 50.45m AOD CSO Weir50.55m AOD Ouseburn (30/6/05)50.78m AOD Ouseburn (20/9/00)51.09m AOD

Proposed development within the Ouseburn catchment 320 Houses on Cell G of Newcastle Great Park Additional Cells of Great Park Hotel Development at Newcastle International Airport Business Park at south side of airport

Proposed peak foul sewage flows from development

2006 onwards Identification of short term measures to prevent flooding (where possible) Commence Feasibility Study – Identify potential solutions (advance works already underway ie flow monitors) Prioritisation of Project in Sewer Flooding Programme Catchment Study incorporating further developments at Great North Park and Newcastle Airport Continued liaison with Red House Farm Residents Association/customers Continued liaison with EA & Newcastle City Council with particular regard to the Atkins Study.

Timescales Cause Report review 15 Dec 05 Identification of short term measures by end Jan 06 Feedback to RHF residents (7/12) and Newcastle Great Park Advisory Committee early Dec 05 Completion of Feasibility Study (relies on weather dependant surveys) Major catchment study planned completion by March 07 Following prioritisation the scheme would be programmed accordingly Construction typically 3 to 12 months depending on size/complexity

QUESTIONS ?