A sweeping examination of how Manitoba, its governments and citizens protect property against flooding has found current standards -- basically protection from a one-in-100-year flood -- to be inadequate. It is at once too risky and it is not practically enforced, two committees that studied the devastating 2011 flood at Lake Manitoba and beyond found. The better yardstick, the reviews conclude, would be to build to a one-in-200-year standard in flood-prone areas.
The current standard, imposed in the wake of the 1997 Flood of the Century on the Red River, no longer is adequate. Raising properties to elevations to fend against a one-in-100-year flood gives good protection in each single year (one per cent chance of flood recurrence), but after 50 years at the same location, the risk rises to 40 per cent. That's unacceptably high, the reviews said.
Further, the current rule has imposed irrational requirements on those rebuilding in the Lake Manitoba area. That's because the rule requires they rebuild to protect for a one-in-100-year flood event, or for the flood of record, whichever is higher. Lake Manitoba residents were forced, therefore, to rebuild to protect against a one-in-800 flood, or, in the case of Twin Beaches, a one-in-1000 flood. That's unfair, the committees conclude because the 2011 flood on Lake Manitoba was, practically speaking, a man-made flood. It is unlikely to recur naturally. Furthermore, the province has said it will build better defences on the Assiniboine and two permanent outlets for Lake Manitoba.
The flood-protection standard needs fixing. But no regulation is worth the trouble if it is not used or enforced. Only one Lake Manitoba municipality required developers to prove their projects conformed to the flood-level rule. Officials said it's tough to turn down development projects that expand their tax base.
For flood-protection rules to work, the province might have to play the heavy with municipalities and developers. The focus, however, should be to arm property buyers or owners with good, useable information to protect themselves. Map flood prone areas and make Manitobans aware, with site-specific information, what elevations are required to protect property from damage, the committees advised.
Developers should be compelled to get certification their project meets the flood-level rule.
These can be practical tools to aid Manitobans, who know they live on an ancient flood plain, but have little good information on how that can affect them, personally. The data and mapping must be nimble to reflect changing risk that reflects an evolving climate and landscape.