| GEOTECHNICAL | CONSTRUCTION | ENVIRONMENTAL
ENGINEERS and SCIENTISTS
Notes from the Frontline -
THE NORTHEAST'S EMERGENCY RESPONSE to TROPICAL STORM IRENE
Tropical Storm Irene damaged Railroad Bridge No. 114 in Chester, VT
Nature's power was unleashed on the northeast beginning on Sunday, August 28th, the day Tropical Storm Irene tracked north from New York City through the northeast states. GeoDesign was contacted by Metro-North Railroad (MNR) late that day to meet MNR engineers at 0700 hours the next morning to respond to a landslide area on the Hudson Line. The site is located in the Spuyten Duyvil area in Riverdale (Bronx), just north of Manhattan and the confluence of the Hudson and East Rivers.
A sixty-foot high earth slope failed during the storm, leaving a very steep scarp at the top of slope at the face of a multi-story building. In response to the event the New York City Department of Buildings ordered the building to be vacated. Earth and mud from the slide crossed over onto Hudson line tracks.
MNR had already cleared the earth and debris from the tracks, but it needed to establish interim repairs and procedures to permit rail traffic, while the private site owner's engineers developed solutions for permanent slope stabilization. The team of MNR and GeoDesign engineers developed a plan to temporarily stabilize the toe of slope necessary for safe train operations and established protocols to slow train speeds based on threshold rates and amounts of rain. MNR mobilized construction forces and the plan was put in motion that day. Trains were rolling by Monday evening.
But, Irene didn't stop in New York. The wrath of Irene moved north and dumped record amounts of rain throughout New England. Rivers in Vermont crested to record highs the next day and many vital transportation arteries were destroyed by flood waters.
After a few days to assess the damage caused by what has been termed a 500 year event, the Vermont Agency of Transportation (VTrans) on September 1, contacted their on-call engineer, Vanasse Hangen Brustlin (VHB). In turn VHB immediately contacted their subconsultant, GeoDesign, to send senior engineers to storm damaged sites starting Labor Day weekend. Over the following weeks and months, GeoDesign's geotechnical engineers joined multi-discipline teams to fast track both design solutions and construction of slopes, highway, and rail bridges that had been destabilized, eroded, and, in some cases, destroyed by extreme high river flows.
Senior engineers developed solutions, both fast-tracked and design-build, on the spot and in the field. Contractors and National Guard construction units began work immediately. GeoDesign worked closely with VTrans and VHB engineers on specific high priority sites, as well as on triage of other sites to help establish priorities.
In particular, the damage caused by Irene to the Vermont rail system, a critical infrastructure to transport commerce and people, was devastating. Most important, the rail system is the primary means to deliver fuel and oil to the City of Burlington, the metropolitan hub of the State. With the system down, Burlington's limited reserve and available highway transport systems simply would not be able to keep up with the fuel demands.
GeoDesign worked closely with VHB, VTrans and their contractors to restore two specific railroad bridges on a line that was categorized as the least damaged. Both of these bridges had major abutment scour damage, and the bridges were impassable. Within 10 days, trains were traveling over these bridges on either temporary or permanently repaired abutments on new driven foundation piling, new abutment stems, backwalls, and approach slabs.
Remarkable progress was made to restore critical transportation facilities in record time. The reconstruction work continued aggressively to help Vermont restore itself for its residents to return to normal life activities, as well as to salvage the fall and winter tourist seasons upon which the state relies heavily for economic vitality.
This type of engineering is unique in that "super-teams" of individuals from engineering firms, owners and contractors are assembled and decision-making is accelerated. Material and equipment availability, access (in Vermont many roads and bridges were closed), time and quality were at the forefront of each decision.
GeoDesign and VHB were two of many engineering firms who responded to tropical storm Irene damage for VTrans, Metro-North and others.
984 Southford Road
Middlebury, CT 06762
224 West 35th St., 11th Fl
New York, NY 10001
54 Main Street
Windsor, VT 05089
1233 Shelburne Rd, Ste. 360
So. Burlington, VT 05403
|Ted von Rosenvinge, P.E., D.GE, is a Senior Principal and co-founder of GeoDesign, Inc. Ted can be reached at
212-221-6652 ext. 1
Jason A. Gaudette, P.G., and
Shawn P. Kelley, Ph.D., can be reached in our Vermont Office