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Washington County has three incorporated communities, Cambridge (pop. 360), Midvale (176), and Weiser (pop. 5,343). The total population for the county in 2000 was 9.977. That is an increase of 17% since 1990.

Transportation

Geography

Land Area: 1 474 square miles.

Historical Background

Established February 20, 1879 with its county seat at Weiser. Named for George Washington, the first president of the United States. Donald MacKenzie was one of the first white men in the area in 1811. Settlers came in the 1860s after gold was discovered in the area.

County Seat: Weiser

Flood - May-June 1998

Event Summary:   Two weeks of rain fell on a melting snow pack, causing flooding along the Snake, Weiser, Payette and Boise River drainages for the second year in a row.  A levee break near Eagle Island caused flooding of nearby homes.

County Summary:  The Weiser River, unable to flow into the swollen Snake River, flooded Weiser for the second time in two years. Businesses, homes and trailer parks along the river suffered flood damage, and schools were closed.  Fields were flooded by 4' of water.  Hwy 71 between Cambridge & Oxbow Village closed by floodwater damage.  Idaho Power closed two parks on the Snake River because of flooding.

The Idaho Statesman, May 15, 17, 28, June 2, 4, 1998

Landslide - December 31, 1997

Event Summary:  Mudslides and flooding along the Payette and Weiser River drainages.

County Summary: Weiser River flooded.

Flood - New Year's Day Storm - January 1-5, 1997

Event Summary:     $65,000,000.00 - New Year's day floods in the Weiser, Payette and Salmon River drainages of southwestern Idaho caused record flooding and numerous mudslides.  Warm temperatures combined with a rainfall 4-6 times the normal amount; the  resulting snowmelt triggered devastating floods, mudslides and avalanches, extensively damaging communities and infrastructure throughout Idaho.  The community of South Banks was condemned because of extensive slide damage.  Over 400 miles of roads and several railroad lines were blocked or destroyed, stranding over 10,000 holiday travelers in western Idaho. Residents of McCall, Cascade, Banks, Lowman and Garden Valley were isolated.  Rivers were "running like chocolate," carrying huge trees, mud and boulders; the Snake River at Hells Canyon Dam crested at 101,728 cfs January 1, nearly 30,000 cfs over its previous record level on 2/23/82.  The crash of a plane carrying 5 people from Boise to McCall, killing all, was a result of the weather.  Governor Batt declared 13 counties a disaster: Gem, Adams, Washington, Idaho, Clearwater, Valley, Payette, Elmore, Latah, Boundary, Bonner, Shoshone and Boise.  A Federal disaster was declared on January 4, 1997.

County Summary: $1,597,318.00 - The Weiser River at Weiser reached record flood level of 16.3', 7' above flood stage.  Homes and businesses throughout the area were flooded.  Cambridge and Midvale reported chest high floodwaters, and a dike near Cambridge  broke.  Hwy 71 was closed west of Cambridge due to mudslides.   45 people were evacuated, and the Red Cross opened a shelter in a local church.  Schools were closed in Weiser, Cambridge and Midvale.

The Idaho Statesman, January 1, 2, 3, 1997, 3/20/97

Drought - 1987-1992

Event Summary:  7 year drought, from 1987-1992.    This period saw the worst water shortage since the 1977 drought.   In 1987, Idaho requested $5.8 million in Emergency Conservation Funds to aid drought-stricken farmers.   In 1988, in Oneida County the Deep Creek Reservoir was shut off half-way through irrigation season because the water level was so low it was filling the sprinkler system with mud and silt.   Throughout the drought, reservoirs were consistently below capacity, resulting in irrigation water ending earlier than normal, crops being plowed under or not planted at all, and recreational activities being curtailed.   The drought caused high water temperatures in rivers,  and the lack of perennial grass growth caused livestock to be removed from public lands early, while wildlife starved in many wintering areas.  Conservation measures were instituted for residential and commercial use.  Wells used for residential and agricultural sectors ran dry, and a moratorium on new wells was instituted.   In 1992 alone, $500 million was lost in agricultural production.

County Summary: 7 year drought (1987-1992) saw the worst water shortage in the state since the 1977 drought.

The Idaho Statesman; Idaho State Journal; Idaho Press Tribune; Times-News; Spokesman

Wildland Fire - 8/1986

Event Summary: Wildfires throughout the state resulted in a state-wide disaster declaration on 8/12/86.  Most of the fires were results of a lightning storm 8/10/86.

County Summary: Wildfire burned 13,000 acres

Lewiston Tribune 8/10/86

Flood - February 1986

Event Summary:   A warming trend melted low-elevation snow packs, triggering flooding and mudslides throughout western Idaho.  Over $20,000 was spent on flood control efforts.

County Summary: Hwy 95 closed between Payette and Weiser, 600 acres of farmland flooded; 4 families evacuated.

The Idaho Statesman February 24, 25, 26,

Flood - February 1982

Event Summary:    Flooding in western Idaho from ice jams and swollen rivers and creeks.

County Summary: An ice jam on the Weiser River caused flooding, forcing evacuations of 20-30 families.  Hwy 95 between Payette and Weiser was closed.  Washington County received a state disaster declaration on 2/19/82.

The Idaho Statesman, 2/17/82

Flood - January 5-12, 1979

Event Summary:  Rain and melting snow ran off frozen ground, causing creeks in the Boise Foothills to rise and a 15 mile long ice jam in the Snake River to break up, resulting in flooding in Boise, Weiser and Blackfoot.  Schools throughout southwest Idaho were closed. Farms, crops, homes and businesses were damaged.  Washington and Bingham counties received a state disaster declaration 1/8/79.

County Summary: Breakup of ice jams in the Snake River caused flooding near Weiser.  8 families were evacuated, farms and houses were flooded with over a foot of water, and Hwy 95 was closed.

The Idaho Statesman, Jan. 12, 13 and 16, 1979

Flood - 1/17-25/1974

Event Summary:    The western part of the state had an extremely cold winter during 1974-75.  Severe storms and snowmelt in January led to flooding.  A federal disaster was declared on 1/25/74. The waters burst dams, blocked major roadways and forced evacuation of at least 1,000 people.

County Summary: 

Idaho Statesman 19 Jan 74

Flood - December 14-26, 1972

Event Summary:     12 days of record low temperatures (as low as -30F) caused ice jams on the Snake and Portneuf Rivers and led to flooding.  The ice in the Snake River between Weiser and Payette was about 12' above the river's normal flow level.  The Snake River ice jam was over 35 miles long, stretched from Farewell Bend, Oregon to the Payette-Washington County line, and grew at a rate of 4.5 miles per day.  Over 90 families were evacuated in Idaho and Oregon, and a "State of Emergency" was declared.

County Summary: The ice jams in the Snake River near Weiser caused flooding of the Snake and Weiser Rivers.  Families were evacuated and Hwy 30 was closed.

The Idaho Statesman December 16, 17, 20, 1972

Pestilence - July 1971

Event Summary:  Grasshoppers destroyed crops in the Magic Valley and Western Idaho.

County Summary: Grasshoppers destroyed 185,000 acres of crops in Adams and Washington Counties.

Flood - January 17, 1971

Event Summary:   Heavy rain and snow over four days caused flooding in southwest Idaho.

County Summary: A mud slide 200-300 feet long closed Hwy 95 south of Midvale Hill.  Homes, schools and businesses were flooded in Council, Cambridge and Midvale after four days of snow were followed by four days of rain on top of an existing 22" of snow.  Ice jams in the Weiser River raised the water level and threatened bridges.

The Idaho Statesman 1/18/71

Flood - December 21-23, 1964

Event Summary:     $21,000,000.00 - During the end of December 1964, warm weather combined with heavy rains and melting snow, causing flooding along the Payette, Big Wood, Little Wood, Portneuf, Clearwater and Boise River drainages.  Hwy 21 and 15, US 95N  and 30E were closed.  Over 100 homes were damaged, numerous bridges were washed out, and thousands of acres of farmlands were flooded.  2 deaths were attributed to the flood.  A state of emergency was declared.

County Summary: Farmland and roads were flooded between Weiser and Cambridge when the Weiser River crested.

The Idaho Statesman 12/24/64

Flood - 2/1-3/1963

Event Summary:     $4,685,000.00 - Heavy snowfall followed by heavy rain caused snowmelt, and combined with large ice jams in several rivers, led to severe flooding in the Clearwater, Boise, Payette, Weiser, Portneuf and Snake River drainages.  Ice jams and high water in the Clearwater River raised the Hwy 95 bridge a foot off of its pilings.  An federal disaster declaration was issued February 15, 1963, for eight Idaho counties due to flooding: Fremont, Madison, Blaine, Owyhee, Bannock, Caribou, Gooding, and Lincoln.  Statewide highway damage was est. at $800,000; damage to county roads est. at

County Summary:  1.5 miles of ice floes in the Weiser River knocked out bridges, and dynamite was used to break them up.  Roads and houses were damaged by 2' of flood waters, ice and debris.  Five families were evacuated.

The Idaho Statesman Feb. 2, 3, 8, 1963

Flood - February 25, 1957

Event Summary: Heavy rain combined with ice breakup on rivers caused flooding in the Little Wood River, Portneuf River, and Weiser River basins.

County Summary: Ice breakup while the Weiser River crested in the Midvale and Cambridge area caused flooding throughout the county. Floodwaters covered parts of Weiser and Hwy 30 with over 1.5' of water, closing the Hwy and isolating Weiser.  Bridges on Monroe Creek and Mann Creek were under water.

The Idaho Statesman 2/27/57

Flood - December 18 - 26, 1955

Event Summary:     $1,500,000.00 - Warm rain on snow led to snowmelt and runoff and  caused extensive flooding in the Weiser, Payette, Boise and Little Salmon River basins.  Payette River peak discharge est. 21,900 cfs.  The flood damaged roads, farmlands and buildings, and caused loss of livestock.

County Summary: $200,000.00 - Floodwaters from the Weiser River destroyed Midvale's water system and washed away parts of 12 streets, flooding nearly every basement in town and forcing eight families to be evacuated. Typhoid vaccine serum was sent to Midvale, and a water filtration unit was put into operation until repairs to the water system were made.

The Idaho Statesman 12/26/55; National Water Summary, 1988-89; USACE "Flood Plain Information Payette, Idaho and Vicinity"

Flood - April 26, 1952

Event Summary:   Rain and high runoff led to flooding of the Snake, Owyhee, Payette, Boise, Big Wood, Little Wood and Portneuf Rivers.

County Summary: Snake River peak discharge est. 84500 cfs, flooded roads between Payette and Weiser, causing 11 families to be evacuated

Flood - January 10, 1949

Event Summary:     Snake River flooding, ice jams

County Summary: Ice jams in the Snake River at Weiser caused flooding.

The Idaho Statesman 12/17/72

Earthquake - February 13, 1945

Event Summary:     Earthquake near Clayton, felt over a 60,000 square mile area.  Magnitude 6, Intensity VI.

County Summary: A magnitude 6 earthquake, centered near Clayton, cracked plaster in buildings at Weiser.

Seismicity of the United States

Flood - December 20, 1919

Event Summary:   Ice jams in Snake River

County Summary: Ice jams in the Snake River near Crystal caused flooding of surrounding farms

The Idaho Statesman 12/20/19

Earthquake - May 12, 1916

Event Summary:  Earthquake in SW Idaho, centered near Cascade.  This quake was felt from Anaconda, Montana, to Reno, Nevada, an area over 50,000 miles, and measured 6.1 on the Richter scale.

County Summary: An earthquake centered near Cascade shook Weiser hard enough that the gas flow pressure at the Weiser Oil & Gas Company plant increased from 45 to 74 pounds, and the well had to be fired to prevent the pipes bursting.

Harpham, Lynda Koll; The Idaho Statesman 5/13/16; 1/31/84; Earthquake History of the United States

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