Saturday, February 9, 2019

Columbia County's Sleeping Dragon: Part VIII

Gossips took a little hiatus from sharing the articles from Margaret Schram's series Columbia County's Sleeping Dragon. Now it's time to resume. Readers will remember that the articles, which appeared in The Independent in the summer and fall of 1988, explored the properties of Lake Albany clay and the problems--historic and potential--created by the clay. My motivation for sharing Schram's research is to make people aware of the problems in the hope that Lake Albany clay, which is a geological factor in Hudson and throughout Columbia County, can be a consideration when proposals for new construction and changes to existing structures come before Hudson's regulatory boards. 

The following article, which is the eighth in the series, was published in The Independent on August 25, 1988.

The Collapse of the Claverack Bridge, February 27, 1918
Adjoining the area of the Knickerbocker Plant disaster, the "Claverack Bridge" crossed the Claverack Creek on what was known as "the Claverack state highway," now Route 23B. The first bridge built over that section of the creek was in the early 1800s, when the Columbia Turnpike was constructed from Hudson to Hillsdale. Prior to that, the route to Claverack was over "Keeler's bridge" off Spook Rock Road (Route 29) and into Claverack by Webb Road. The meadow just west of the creek was frequently flooded, so double bridges were built: one over the creek connected to another over the hollow. For nearly 100 years, until the state took over the highway, two wooden bridges spanned the creek and field.
When the state constructed the concrete structure just about eight years before this event, they built a 240-foot cement slab bridge over the creek and the hollow. It consisted of eight 30-foot spans, and the bridge was supported by piles 65 feet long, driven into the creek. Heavy abutments supported each end.
Might Be Trouble
At the time it was built, "one or two local contractors had pointed out that there might be trouble later on." 
Snowfall had been unusually heavy during the winter months of 1918, and a late February thaw sent the Claverack Creek over the banks, filling the hollow next to the bridge with high, swirling waters. The evening of February 27, a heavily loaded truck passed over the bridge and noticed nothing out of the ordinary. Three Hudson residents were returning to Hudson from Claverack shortly before 9 p.m. on that same evening driving "along at a rapid rate in a high powered runabout," when they started over the bridge.
Yawning Chasm
They discovered that the center of the bridge was a "yawning chasm," with two sides holding together at the bottom, each slab at a 45 degree angle.
On the Hudson side, the massive concrete structure had pulled away from the abutment, leaving an opening of over seven feet directly over the surging waters. The driver accelerated and sped down the first incline, flew over the gaping crack and up the inclined western slab. The car was going so fast that when it cleared the top of the tilted slab on the Hudson side, it was suspended momentarily in the air, and then plunged to the ground. The force of the crash catapulted the occupants some 10 to 20 feet. The three escaped serious injury, but the car was totally wrecked.
Two Spans Sank
The bridge section on the western side continued to sink at a rate of six inches an hour. During the next day, it continued to slump until the two spans sank beneath the waters. The abutments on each side were holding, but only the reinforcing steel cables held the sunken spans, estimated to weight 1,000 tons. The bridge was closed to all traffic.
On March 4, a committee from the Towns of Claverack and Greenport met to solve the problem of the bridge. If they waited for the state to repair the damage, it would require official approval and 30 days bidding time, with no bridge in place before summer.
The following day, the combined group drafted a resolution. (This is courtesy of the Town of Greenport minutes of 1918. I have taken the liberty of abridging, especially removing innumerable uses of "whereas" and "the said.") "The gap must be filled by commissioners of both Towns with consent of both Towns--To make a fill by both Towns is legal and both Towns take the responsibility of paying half."
Towns Rebuild
The resolution read: "The Towns of Claverack and Greenport are now jointly liable to make and maintain a bridge across the Claverack Creek. On the 27th day of February 1918 the western portion of the bridge from the extremely westerly abutment, extending to the second abutment easterly had collapsed and fallen down by means of a freshet or otherwise, and it is therefore wholly destroyed and impassable."
The resolution went on to describe the inspections and "also the question of converting the space spanned by the fallen portion into a solid approach. . . . Resolved that to meet the emergency it is not expedient to build the fallen portion as a bridge--but to extend the westerly approach to meet the portion still intact."
The solid fill over the hollow (and the sunken bridge) was to be 34 feet wide, 12 feet deep, and 54 feet long. The roadway was to be of stone and cinders and level from the existing road to the bridge span over the creek.
$944 Cost 
An expenditure of $800 was approved by both boards, but the bid came to $944, which included guardrails on each side of the new section. That amount was authorized. The work was done as soon as the flood waters receded, with plans for a more permanent roadway "when the frost has left the ground."
On March 22, 1918, the new road was opened to traffic. "Users are cautioned to proceed slowly over the bridge. . . . The Towns, however, assume no liability pending the completion of the repair and legal opening of the closed highway."
The next time you drive over that bridge remember that, for a least 50 feet beyond the western edge, there once was another bridge, and that its remains most likely lie deep under today's highway.
Quicksand Blamed
Again residents blamed quicksand for the collapse, but it was Lake Albany clay up to its usual tricks. Geologists reported that the stratified gravel near the surface slipped on the saturated clay beneath. The weight of the bridge, combined with the pressure of the flood waters against the piers, caused the piers to slip and fail; the two spans of the bridge were carried down. There was little or no damage to the concrete slabs themselves; the problems originated in unstable foundation of the bridge.
Today's Questions
My questions today are: Has the bridge and the surrounding area been stabilized so that an event such as this cannot recur?
Between August 1953 and May 1954, New York State "completely rebuilt the "Claverack Bridge." It was widened from a narrow two-lane structure to the present width. A great deal of time was spent in sinking adequate pilings to hold the weight of the bridge.
The bridge on Route 23B was most recently repaired in the summer of 2013, when the bridge deck was replaced with concrete, the steel beneath the bridge was repaired, and new railings were installed. In my search to confirm the nature of the repairs made in 2013, I stumbled upon this picture on the Town of Claverack website, which shows the bridge in September 1938, after it had been washed away during a hurricane.

The following are the links to the previous articles in the series Columbia County's Sleeping Dragon.
Part I: Landslides a Deadly Threat to a Growing Community
Part II: Prologue--Lake Albany
Part III: An Industry from Lake Albany Clay
Part IV: Industries from Lake Albany Clay
Part V: The Stockport Slides
Part VI: Knickerbocker Cement Plant Tragedy, August 2, 1915 
Part VII: Section 2 Knickerbocker Cement Plant Tragedy, August 2, 1915

1 comment:

  1. Wow, that's quite an account, Carole. One can picture the whole scene as it unfolded. People in a car on an idyllic country drive, when suddenly the road drops off and the driver accelerates, becoming airborne, with a hard landing and people and car parts flying all directions. Like something out of a Harold Lloyd movie. Who knew?