Flash Flood — Ottawa, Michigan

1997-06-20 to 1997-06-21 · near County-wide, Ottawa, Michigan

Event narrative

Slow-moving thunderstorms developed over Lake Michigan and moved east across Ottawa County throughout the day of Friday, June 20th. With the soil already saturated from 2 to 4 inches of rainfall from this training effect of thunderstorm activity during the day, a line of severe thunderstorms developed early Friday evening and moved across the county, depositing another 1-5 inches of rainfall within a 2 hour period, causing widespread flash flooding. Southern Ottawa County bore the brunt of the flash flooding,including the cities of Holland and Zeeland, Zeeland Township, Jamestown Township, Holland Township, Wright Township, and Chester Township. Notable rainfall totals for the 24 hour period ending at midnight included 5.47 inches in the city of Holland, 9.16 inches at Holland State Park, and an unofficial report of 13 inches of rainfall in Zeeland. Extensive damage was done to roads, bridges, and homes. Approximately 44 roads were flooded including parts of U.S. Highway 31. Of this number, 40 roads were deemed impassable due to washouts. During the peak of the flash flooding, many motorists were stranded for several hours until emergency personnel could free them. Shortly after midnight, a U.S. Coast Guard helicopter rescued four occupants off the top of their overturned car stranded in deep water at 80th Avenue and Adams Street in Zeeland Township. The Coast Guard rescued a total of 12 people from stranded vehicles Friday evening. In addition to the road washouts, 6 bridges were damaged. Zeeland officials reported 15-20 percent of the city's streets were flooded during the peak of the storm. In addition, 2 sewage lift stations were disabled, causing sewage backups at many residences. Ottawa County officials reported approximately 150 homes and 11 businesses damaged. Most of the damage was from flooded basements. No injuries were reported Friday evening. However, 2 boys, aged 12 and 11, received minor injuries Saturday afternoon when their raft overturned in the swollen north branch of the Black River in Holland. On Monday, June 23rd, Ottawa County declared a local State of Emergency. On Friday, June 27th, Governor John Engler issued a state disaster declaration for Ottawa County as a result of the widespread flooding damage.

Wider weather episode

During Friday, June 20th, very warm, moist and unstable air was in place across much of Michigan's Lower Peninsula, ahead of a strong, slow-moving cold front across the western Great Lakes region. Atmospheric conditions were ripe for the development of strong to severe thunderstorms containing wind gusts to 70 mph and very heavy rain. Numerous thunderstorms reached severe criteria due to damaging wind gusts. However, the most significant damage was caused by flash flooding across Allegan and Ottawa Counties, which was caused by the training effect of slow-moving thunderstorms during the day, followed by a line of severe thunderstorms which moved through during the early evening hours. Thunderstorms during the day saturated the soil across the counties, then heavy rainfall of 1 to 5 inches in a 2 hour period from a line of severe thunderstorms during the evening created extensive runoff, resulting in extensive flash flood damage.

Source: NOAA Storm Events Database, event_id 5618578. Narrative written by the NWS forecast office that issued the report.