Flooding
Like many other areas of British Columbia, the Central Okanagan may be threatened by floods. No matter the cause, be it run-off from melting snow or a sudden onset resulting from rains and storms, being aware of the potential danger is critical.
View where you live with a critical eye. If you live near a lake or water course, is there a potential for flooding? While some floods are unavoidable, others are predictable and mitigative work will lessen or eliminate damage as a result.
Freshet is the period of time in the spring (typically April to July) where creeks and rivers swell from snowmelt. Freshet flooding can generally be forecast using information relative to snow packs, predicted weather and knowledge of stream channel capabilities. These forecasts generally create a foundation for an enhanced level of readiness.
Localized weather during the colder months may cause ice jams anywhere on a stream. Floods typically first occur upstream of the jam until the reservoir formed behind the dam breaks through or finds a way around it. Stream level changes may be gradual or very rapid. A slope failure with resulting debris (trees, large rocks, etc.) could create much the same situation.
Within the Regional District of Central Okanagan, the regional emergency program is in place to ensure a proper response to emergency situations, including flood events. For more information click on the link on the left side navigation bar.
Flood Management Response
The response is broken down into four phases:
1. Planning: monitor stream levels, provide oversight to dam and dike owners, continue efforts in planning and exercises and provide for mitigation. At this stage, when required, a flood observer/assessor may be assigned to identify and monitor any sites at risk.
2. Preparedness: this occurs when a flooding potential is possible. Special resources may be pre-positioned and advisories prepared. The Emergency Operations Centre (EOC) staff may be contacted and plans reviewed.
3. Response: flooding is imminent and/or occurring or when an emergency response is initiated. This normally occurs when a stream stage (water height) is expected to reach or exceed stream channel capacity resulting in flooding. EOCs will be activated relative to the level of response required. This response phase is broken down into stages and will generally depict the level of activation required:
- Flood Alert: local authorities will actively patrol stream banks. Dam owners should increase the monitoring of their structures and ensure that spillways are clear and in working order. Public information on flood-proofing threatened structures as well as public safety advisories will be issued. Evacuation plans would be updated as necessary for potentially affected areas.
- Flood Order: this occurs when there is a high probability of damage due to flooding. Mandatory evacuation may be contemplated or ordered.
- All Clear: this is realized when the threat of ongoing flooding has past and evacuees may return to the flood area on a permanent basis. Outstanding issues such as building occupancy due to electrical problems or drinking water contamination may persist, however, people may proceed with cleanup activities.
4. Recovery/Disaster Financial Assistance: This phase begins when flooding is over and the replacement and restoration of uninsured essential property to pre-event condition commences. This may include debris and gravel removal, as well as incremental costs for a local authority’s Recovery Centre. Public information will be provided to assist residents of impacted areas about the health risks they may encounter, how to clean up flood impacted property and structures, how and where to go to access Disaster Financial Assistance information, and other sources to assist people in need.
