During my research work on the Community Resilience to Extreme Weather (CREW) project some years back I talked to policy-makers, national and local government officers, and utility staff about various flood risk and drainage planning issues. Often they explained to me how difficult it would be to finance major increases in resilience to flood risks via more storage and/or diversion of water flows to handle more periods of intense rainfall (which are predicted to become more frequent as the climate changes in the UK).
Once a year I get a stark reminder of one of the reasons why: cost. Over the past week or so I again watched a procession of EA contractors turn up, fence off, then dredge a very small culvert near where I live:
Even a cursory glance at the flurry of activity and heavy vehicles present during these days highlights the public money needed to maintain these assets. After witnessing the time and effort involved to keep just one culvert from blocking up it’s clear how challenging it would be to add many new culverts and storm flow storage facilities into the system, as they’d clog up with runoff material and need maintenance. One can only imagine the costs multiplied across the whole country…
But of course luckily we don’t have to imagine, as the EA has kindly made public a postcode-searchable database of its routine maintenance jobs on these kinds of assets (and the April 2013 to March 2014 database for this alone is a 38 MB Excel file!). The work I’ve seen seems to account for about 50% of the EA’s annual maintenance schedule, at a cost of around £20 million a year apparently (albeit this total includes broader in-channel river clearing too).
Whether we’ve reached our ‘economic level’ that’s a trade-off between growing maintenance costs and installing new infrastructure, I don’t know. However our nearby annual clean-up is always a reminder that there’s no fit-and-forget when it comes to these kinds of increased flood resilience assets; they sadly all come with an ongoing cost!