( CNN ) -- Rain-swollen rivers have inundated highways and farms , towns and parks in western Washington , shutting down traffic on a 20-mile stretch of heavily traveled Interstate 5 between Seattle and Oregon and threatening the federal roadway north of Seattle . Flooding forces officials to close a road in Arlington , Washington , north of Seattle . `` If you 're trying to do commerce between Portland [ Oregon ] and Seattle , there is no way right now , '' said Bob Calkins , a spokesman for the Washington State Emergency Operations Center in Camp Murray near Tacoma . `` That 's the major way into Washington state from Oregon . '' Flooding south of Seattle near Chehalis covered parts of I-5 with 30 inches of water , prompting its closure until at least Monday , state transportation officials said . And state and local roads also were victims of the water . `` The problem is the one real good detour is just as flooded , '' Calkins said . North of Seattle , a levee failure in Arlington brought the Stillaguamish River up to the edges of I-5 , which remained open although some access ramps were closed , transportation officials said . The rain also caused Amtrak to suspend service between Seattle and Portland until Saturday , `` with no alternative transportation , '' the rail line said on its Web site . iReport.com : Are you there ? Share pics , video . On Friday morning , the National Weather Service extended flood warnings for parts of six rivers that flow through five counties in western Washington near Seattle and Tacoma . Those affected included Puyallup River near Orting , Newaukum River near Chehalis , White River near Buckley , Cowlitz River at Randle , Skookumchuck River near Bucoda and Centralia , and the Chehalis River at Centralia and Porter and near Grand Mound . The weather service canceled flood warnings for two rivers -- the Nisqually near National and the Deschutes near Rainier . This week 's flooding has caused hundreds of families to evacuate , according to the Washington Emergency Management Division . It prompted 18 counties and 13 cities to declare emergencies , the division said . Across the state , a number of rivers had crested , but flooded roads remained hazardous . The risk of landslides was high , leading to the closure of all passes across the Cascades , officials said . Watch a report from CNN affiliate KIRO about landslide risks » . A meteorologist for the National Weather Service in Seattle said 15 inches of rain that began Monday had ended . The rainfall swept across virtually all of the state , but its biggest effects occurred along the western half of Puget Sound , Calkins said . The swollen Puyallup River threatened the town by the same name , but Loretta Cutter sprang into action . The administrator of a group home and a longtime resident there helped evacuate 47 residents from the Valley Community Inn , a home for the mentally challenged and developmentally disabled , to a shelter at a nearby church . And she made sure her husband and a grandson left their one-story rambler house and got safely situated . `` It 's a situation you do n't realize you are going to be in ; it 's always someone else , '' Cutter said from the shelter at the Sunrise Baptist Church in Puyallup , east of Tacoma . `` It was pretty traumatizing to all of us . '' Cutter is one of 40,000 residents in at least 19 communities whom authorities asked to leave their homes Thursday amid heavy flooding along rivers and streams in western Washington . Some 260 of them sought shelter Wednesday night at the 39 shelters for people , Calkins said . In addition , seven livestock and two pet shelters were set up , he said . Meanwhile , the torrential downpours of the past few days transformed Thursday into drizzle , common in western Washington , which typically gets less rainfall in any given year than does Miami , Florida . `` It just drizzles every day , or so it seems , whereas in Miami , when it rains , it 's a belly washer , '' Calkins said . This week 's flooding was worsened by a warm spell that melted up to 7 feet of snow that had fallen around Puget Sound , he said . Health authorities have issued occasional boil-water orders , but Calkins said he had other concerns . `` The larger issue is , as people go to their homes , they may be walking through floodwater that is contaminated by sewage , '' he said .
NEW : Flood warnings extended for parts of 47 rivers in western Washington . A stretch of Interstate 5 between Washington and Washington remains closed . KIRO suspends service between Seattle and Washington , Oregon , until Saturday . Up to 15 inches of rain reported in some areas of Washington state .