Flood — Okanogan, Washington

2018-05-09 to 2018-05-23 · near Oroville Scott Arpt, Okanogan, Washington

$2.0M

Property damage

Event narrative

The rise on Osoyoos Lake, which has no official Flood Stage, began to flood properties and seep into homes around the lake shore beginning on May 9th. By the morning of the 10th flood waters had submerged Deep Bay Park and were flooding the basements and threatening the first floors of homes along Blackler Road and the boat launch along Veranda Drive. As the lake crested and the level stabilized between May 11th and May 19th extensive flooding of low lands along the lake was noted with Veterans Memorial Park completely inundated. Numerous lake shore homes suffered first floor flooding during this crest period.

Wider weather episode

Warm temperatures in early May prompted accelerated snow melt in the mountains of British Columbia. Run off from this snow melt caused multiple areal flooding issues in Okanogan County during the second and third week of May. Lake Osoyoos began rising rapidly during the second week of May. Flooding occurred on properties along the lake shore during the second and third weeks of May as the water level peaked and stabilized. The water level began to recede on May 19th and continued to fall through the end of the month.

Salmon Creek near Conconully also rose out of it's banks due to snow melt in the higher elevations of the north Cascades. This river caused minor flooding problems in the town of Conconully and lead to a road closure along the southern stretch of river.

The Chewuch River draining the north Cascades through Winthrop also rose out of it's banks causing minor flooding of roads and a few homes in the Winthrop area.

All of these flooding issues along with the major flood along the Okanogan River prompted the county to be included in a State of Emergency Declaration issued by the Washington State Governor.

View location on OpenStreetMap → (48.9980, -119.4612)

Source: NOAA Storm Events Database, event_id 758793. Narrative written by the NWS forecast office that issued the report.