In addition to a wet March, periodic heavy rains continued during the month of April. In Ferry County, the COOP station at Republic recorded 2.93 inches of rain for the month, which is 1.42 inches above average. In Okanogan County the Omak ASOS station recorded 2.66 inches of rain, which is 1.62 inches above average. At Mazama the COOP observer recorded 2.45 inches of precipitation, which is 1.42 inches above average.
All of this rain on top of spring time snow melt promoted saturated soil conditions which resulted in numerous debris flows and areal and small stream flooding issues through out Ferry and Okanogan Counties during the month of April.
Ferry County had been experiencing these issues through the end of March but more rain in April aggravated the situation resulting in major debris flows and flooding which cut key roads through the county. The Sanpoil River also flooded to levels which a media statement issued by the Ferry County Sheriff's Office and the Colville Tribal Police described as the worst flooding in decades.
Okanogan County largely escaped problems during the month of March but April brought the axis of periodic heavy rain storms and accelerated low elevation snow melt to this county. Saturated soil conditions, often over extensive recent burn scars,  resulted in numerous debris flows and small stream floods which disrupted travel for much of the month and isolated a few back country residents for long periods of time.  Highway 20, one of the major roads through the region remained closed over Loup Loup Pass while major repair work continued into the month of May.

Flood in OKANOGAN, WASHINGTON
From 04-APR-17 00:00:00 to 30-APR-17 23:59:00 (PST-8)
Location: MAZAMA ARPT
Flood cause: Heavy Rain / Snow Melt
Property damage: 4.00M
Crop damage: 0.00K
Reported by: Emergency Manager

Areal Flooding, mudslides and debris flows in rough terrain plagued Okanogan County during the month of April as a result of saturated soil conditions brought on by periodic heavy rain and spring snow melt.
At least 24 roads through out the county were closed or damaged by washouts and debris flows during the month.
Most notably, State Route 20, a main east to west route between Twisp and Okanogan was cut by a washout on April 7th near mile post 221 and then suffered a second washout on April 15th near mile post 211. Both washouts cut deep chasms through the road bed and closed a 10 mile section of the highway through the rest of the month and into May. Five residences between these washouts were isolated while the road was repaired.
A second major route through the county, State Route 153, was cut by a debris flow on April 7th causing a temporary closure of a three mile stretch near Pateros.
Salmon Creek near Conconully flooded and damaged summer homes and properties along it's banks.

Flood in FERRY, WASHINGTON
From 01-APR-17 00:00:00 to 28-APR-17 00:00:00 (PST-8)
Location: KELLER
Flood cause: Heavy Rain / Snow Melt
Property damage: 1.50M
Crop damage: 0.00K
Reported by: Emergency Manager

Ferry County was affected by numerous road washouts due to areal flooding and debris flows during much of the month of April. Travel was disrupted through out the county with at least 20 roads closed or reduced to one lane due to damage.
The most notable road closures include Highway 395 near Boyds, which suffered a 100 foot section of the road washed away into a 20 foot deep chasm on April 13th, and Highway 21 where a temporary one lane bridge was constructed to cross a 100 foot total washout of the road 15 miles south of Republic, and the Inchelium Highway near Inchelium where a debris flow cut the road on April 15th. All of these roads are major north-south highways through the county.
The Sanpoil River flooded during this period causing one house to wash away into the river and threatened another home as the flood undermined the bluff it was located on.