Reservoir Flood Buffer

Year
2010
Number
B67
Sponsor(s)
Coquitlam

WHEREAS the establishment of reservoir flood buffers, storage space to contain flood flows, at BC Hydro facilities is a very cost-effective method of providing community flood protection that reduces the need for expensive dike upgrades and river dredging commonly funded by the Province and local governments; AND WHEREAS there are many beneficiaries to flood buffers but local governments are often the sole payers of compensation to BC Hydro: THEREFORE BE IT RESOLVED that that Union of British Columbia Municipalities request that the Province of British Columbia direct BC Hydro to establish flood buffers for community flood protection purposes at their reservoir facilities where economically viable; AND BE IT FURTHER RESOLVED that the Province of British Columbia be requested to compensate BC Hydro for lost power generation revenue through remissions to their water rental fees, if necessary.

Provincial Response

Ministry of Energy BC Hydro has an agreement in place with the Cities of Coquitlam and Port Coquitlam Cities to provide a flood buffer. This service is provided at a cost to the Cities of about 35,000 per year per municipality. Responsibility for flood protection lies with the municipalities that develop in the flood plain, subject to BC Hydro or any upstream works not exacerbating downstream flood risk. BC Hydro is amenable to considering additional flood protection, but it would do so insofar that their rate payers are kept whole and BC Hydro takes on no additional risk or liability for doing so. The cost charged to the municipalities is far less than the millions it would have cost the municipalities in terms of development restrictions and dyke upgrades.

Other Response

BC Hydro BC Hydros dams provide indirect flood protection through the presence of works and the moderation of inflow events through normal operations. Local governments downstream of these facilities currently receive these ancillary benefits at no additional cost. First, it is important to recognize that dams are designed to spill during periods of heavy inflows, and BC Hydro may discharge water similar to natural, unregulated flows in order to maintain the integrity of its works. The use of a flood buffer can only reduce the frequency of lesser flood events; it cannot prevent flooding, nor can it necessarily reduce the impact of large inflow events. Flood plain development ultimately remains at risk to events beyond BC Hydros control, with or without a flood buffer in place. Additionally, it is not clear that flood buffers are a very cost-effective method of providing community flood protection compared to other alternatives. Reductions in reservoir operating range have significant and ongoing cost implications for ratepayers; these would need to be compared, in each case, to the costs of other flood protection measures before a determination could be made on relative cost-effectiveness. Finally, subject to regulatory requirements, BC Hydro reservoir storage is optimized for the net benefit of the electrical ratepayer. Use of a reservoir flood buffer for the benefit of select municipalities reduces the amount of firm energy available as well as BC Hydros operational flexibility, at a net cost to all ratepayers. Further, the Water Act Regulation does not permit compensation of lost power generation through remissions, outside of minor, incremental changes made during the Water Use Planning process. When this issue was considered in 20052006, the Provinces view was that responsibility for flood protection remains with local governments that manage development on flood plains. We appreciate the opportunity to provide comment on the UBCM resolution, and continue to work cooperatively with local governments to ensure effective communications during unusual inflow events. We remain open to further exploring opportunities to reduce flood risks for communities, where there is no additional impact to the electrical ratepayer.

Convention Decision
Endorsed