IT’S IN THE EYE OF THE INSPECTOR Overview of visual inspection methods in four countries and lessons learned ISFD4, Toronto 6 May 2008 Jaap Flikweert

Background Based on study for NL Research programme ‘Inspection of flood defences’ (VIW) (STOWA & Rijkswaterstaat) Co-author: Gerard Moser Sources: n Personal involvement in NL & UK n Literature study & interviews for FR & DE

Lay out of presentation Why inspect? Role of visual inspection Local context Methods Conclusions on effective use of visual inspection

Asset management Flood risk management  Risk-based asset management Balancing risk, cost and performance Why inspect? To measure deterioration To steer intervention To improve performance To reduce risk graphic: Advantica Ltd.

Asset Inspection Parallel with human health

Asset inspection Visual, intrusive, remote Judgement, guidance, calculation Tradition, performance based

Role of visual inspection Drivers for developments: n Defences protect more n More complicated structures n Professionalisation n Technological development Why still visual inspection? n Use of local knowledge n Cost n Human factor n Emergency staff available

Local context

Netherlands: Flood risk dominant, defences vital, long history Strict legal framework, flexible application Focus on meeting standards Assets managed by professionals Germany (Federal waterways): Flood risk significant, defences very important Strict procedures Focus on preventing damage Assets managed by professionals England: Flood risk significant, increasing profile, defences locally important Permissive powers, strict procedures Focus on cost-effectiveness and risk Assets managed by professionals France: Flood risk significant, defences locally important Guidance Focus on introducing defence management Varying but improving quality of asset management Scale of flood risk Rules Focus Organi- sation

Methods Long tradition of visual inspection Recent years: less embedded in asset management

Methods Why: Identify & repair small defects Limited link with asset management  under development How: No detailed rules, left to local judgement Guidance under development Who: Operational staff Recent development: training available

Methods Focus on Federal waterways Framework: n DIN flood embankments n Specific internal directive for inspection Clear hierarchical structure: n Inspector: inspect and inform n Field officer: check, respond and inform n Asset manager: check and respond Indicators are asset specific & failure mode related

Methods Why: Identify defects, prevent breach How: Detailed roles Asset specific indicators Who: Specialist full-time inspectors Backed by experts

Methods Since mid 90s: Condition Assessment Manual: n Condition grade (1-5) n Nationally consistent n Indicator for performance Developments: n Improve link with failure modes

Methods Why: Keep track of deterioration Measure maintenance quality How: Detailed prescribed roles Systematic technical guidance Who: Operational staff with specific training

Methods Longer tradition of dam management, but flood defence management just starting Opportunity for integrated approach: n Performance based n Inspection embedded in asset management Guide pratique (Cémagref): n Procedures n Set of forms

Methods Why: Identify defences and determine starting point Move toward keeping track of deterioration How: General guidance on approach Can be applied to set local indicators Who: Variable, depends on asset management organisation

Conclusions n Each country / culture its own method n Visual inspection can have different purposes n General move toward performance based inspection n Specific role for visual inspection within overall inspection, given technological developments: n Taking the pulse n Trigger for expert inspection n Input for modelling