Credit: NASA/NOAA GOES Project

Although Hurricane Ike is long gone, its impact lingers more than a thousand miles from where it made landfall. Runoff from tributaries dumped massive amounts of sediment into Lake Michigan, contaminating the water, compromising near-shore navigation and raising E coli bacteria to levels unsafe for swimming. The local effects that Ike had on Lake Michigan’s Indiana shoreline, water depth, and water quality have been profound.

The remnants of Hurricane Ike passed over northwest Indiana soon after a stalled cold front had deposited several inches of rain on the region. Recorded total rainfall amounts from the two events ranged from 8-12” and as a result, several sewage treatment plants with combined sewage/stormwater systems were forced to bypass their combined sewage into receiving rivers and creeks. The accumulated runoff and sewage raised local tributaries and caused massive flooding throughout the region.

Along Burns Ditch, the outfall of the Little Calumet River, gage heights and flow velocities reached record levels, as recorded by USGS instruments, which caused flooding and massive damage to local marinas. As the water flowed into Lake Michigan, USGS instruments detected huge amounts of suspended sediments that created new shoals in the harbor and greatly increased water turbidity. The velocity and height of a tributary emptying into Lake Michigan at Portage, Indiana went off the chart. We measured a tremendous amount of sediment accumulation Near Ogden Dunes. Data collected by USGS immediately after the storm was used by the US Coast Guard and US Army Corps of Engineers to assess shoreline impacts of the storm and to estimate whether a beach is unsafe for swimmers.

On September 16, 2008 Great Lakes Science Center personnel attending the Great Lakes Beach Association meeting in Indiana Dunes recorded this video (no audio) of the damage to the Burns Ditch area. Meeting attendees got to experience first-hand the impacts of such a major storm on bacteria concentrations in beach water and to see the benefits of USGS efforts to improve beach health. If your browser will not display the embeded video, please use this link, Burns Ditch Video, to view it in your system's default media player.

The following images were taken by scientists at the Great Lakes Science Center's Lake Michigan Ecological Research Station at various times in the Ogden Beach area of Indiana Dunes, near Burns Ditch, and depict some of the damage to the Lake Michigan beaches. Roll over the thumbnails for larger images and descriptions.

Images from of the damage at Ogden Dunes Beach.
Sept. 17, 2008, after the storm. Wood debris and crushed boats at Ogden Dunes Beach close to the seawall looking west.

Bacteria and sewage contamination also flowed into the lake, raising E. coli levels. Even a week after the inundation, the beach area was still feeling the effects of these rainstorms: USGS scientists measured E. coli concentrations as high as 1200 CFU/100 ml (a single sample measure of 235 CFU/100 ml results in issuing a swimming advisory). Beaches around the Burns Ditch area were closed due to high bacteria concentrations and the massive amounts of debris washed up on the beaches. Sediment shoaling kept the harbor closed to boat traffic.

As part of USGS efforts to improve predictions of beach water quality, scientists had numerous instrument installations that were used to follow the storm event’s effects on area beaches. Typically, storm events raise bacteria levels along nearshore Lake Michigan when runoff increases E. coli concentrations in the water. The massive rain event ending with the remnants of Hurricane Ike provided USGS scientists with a great amount of data on storm effects on beach water quality.

The USGS invites you to explore the scientific information it continues to gather on the nation-wide effects of hurricane Ike at: Science that Weathers the Storm: USGS Responds to Hurricane Ike.

For more information about the effects of hurricane Ike on the Great Lakes:
Dr. Richard Whitman
Lake Michigan Ecological Research Center
rwhitman@usgs.gov
tel: (219) 926-8336, ext. 424
fax: (219) 929-5792