| Event |
Flood |
| -- Flood Cause |
Heavy Rain / Snow Melt |
| State |
IDAHO |
| County/Area |
BONNER |
| WFO |
OTX |
| Begin Date |
03/30/2012 16:00:00 PST-8 |
| Begin Range |
1 |
| Begin Azimuth |
NW |
| Begin Location |
WESTMOND |
| Begin Lat/Lon |
48.14/-116.62 |
| End Date |
03/31/2012 11:59:00 PST-8 |
| End Range |
1 |
| End Azimuth |
NW |
| End Location |
COCOLALLA |
| End Lat/Lon |
48.11/-116.64 |
| Deaths Direct/Indirect |
0/0 (fatality details below, when available...) |
| Injuries Direct/Indirect |
0/0 |
| Property Damage |
550.00K |
| Crop Damage |
0.00K |
| Episode Narrative |
A stagnant longwave pattern featuring a broad trough off the Pacific Northwest Coast and upper-level ridge over the Central US resulted in a parade of moist storm systems tracking through the Inland Northwest from March 28th through the 31st. Each storm system deposited 0.25 to 0.75 inches of rainfall across most locations in the Idaho Panhandle with three day rainfall totals ranging from one to three inches. This concluded record setting precipitation totals for the month of March. With soils already saturated from heavy rain just a few days earlier and above normal snowpack still in place in the mountains, portions of North Idaho experienced numerous floods, road washouts, and debris flows. The most significant damage occurred in Bonner County which involved a train track washout, train derailment, and washout of a hundred foot length of road near Cocolalla Lake. |
| Event Narrative |
High runoff and saturated grounds from a month of record rainfall combined with excessive snow melt resulted in a major road washout under a section of Cocolalla Loop Road. It was estimated that 25 feet of earth below the road, roughly 100 feet in length, was washed down the hillside as the underground culverts became overwhelmed or clogged. The road washed out on March 31st. Additional flooding was observed along the northeastern shores of Lake Cocolalla, specifically Melody Lane, where several secondary, recreational houses were inundated with water from the swollen lake. Minor damage was also observed at a small wooden bridge where Cocolalla Creek crosses under Cocolalla Creek. |
