Emergency Response Construction

Kip Lindman | September 28, 2010

Natural disasters can be devastating to the communities affected by them. While the disaster is in progress, people hold out hope for a positive outcome. But in many cases these events cause traumatic damage to an area.

After Mother Nature subsides, communities, governments and economies begin the rebuilding process. Contractors are often called to provide emergency relief, and often it is the promptness of their response that determines the future of damaged property.

In late 2007, Western Washington area felt the wrath of a natural disaster in the form of severe flooding. Floodwaters reached houses and businesses and broke through seawalls without any regard. Property owners immediately looked for ways to save their homes, businesses and livelihood.

The Call to Duty

When the disaster struck, Whatcom Waterfront Construction, based in Bellingham, Wash., stood ready come to the aid of those affected.

"We don't like to say no to any job," said Tracy Diller, co-owner of Whatcom Waterfront Construction. "The flood affected everybody in the area. Fortunately, we had the tools and ingenuity to help one extremely damaged property rebuild."

While the storm still raged, Diller's crew raced to a waterfront property on the Olympia Peninsula, a site of heavy devastation. A seawall was found to be completely missing, blown out into Hood Canal, compromising an area that had been safely protected for years. The crew assessed the damage, realizing the wall had to be replaced quickly to prevent further loss to the property.

"I gathered the crew; my construction cowboys. They were more than willing to push other things aside and help out in the treacherous weather. It's what we do," Diller said.

If Whatcom's crew hadn't responded rapidly, the eroding area they were assessing would have given way to the continued flooding. Ultimately, there would have been a house in the water. Structurally, the house would have been a complete loss.

The tremendous hydraulic pressure of the water building up behind the 60-foot-long seawall had completely blown it out into Hood Canal, 18 horizontal feet. The wall was found resting 15 feet below high tide in three sections. The loss of soil behind the seawall was in excess of 75 cubic yards, causing 20 percent of the structure to teeter over the edge of the water. The property was being undermined by the minute as the rain continued to fall.

Options Limited

Analyzing the situation, Diller saw he had to deal with extremely saturated soil and a bank that was continually calving by the hour from high water rushing back to sea level.

Equipment options were limited. The crew members inserted themselves on the toe of what was left of the remnant seawall. After evaluating the operation area, they noticed three obstacles:

  • Densely saturated soil;
  • A rising tide that took over the working platform twice a day;
  • Steep banks with no route for equipment to travel.

Their mini-crane was now able to make its way to a safe spot of land towards the crippled seawall.

"Our mini-crane was in position. We just had to figure out how our ASV RC-30 — often called our Whatcom Workhorse — was going to get down there," Diller explained.

The RC-30 is a small, maneuverable compact track loader that has all the credentials needed for the job. Whatcom had used it to drive pile, work in cramped areas and float atop saturated soil with its mere 2.8-psi ground pressure.

Whatcom rigged the RC-30 with a bucket attachment, attached the machine to the mini-crane and lowered it onto the working platform next to what was left of the seawall. Once in place, Diller had only five feet to maneuver. On his left was the receding bank; to his right a 45-degree slope leading into the water. The tide would eclipse the cramped worksite at certain times, making the 45-degree angle steeper as time passed.

Using the ASV RC-30 and bucket attachment, Diller cleared a path large enough to determine that the base of the seawall was a separately poured concrete footer. The separately poured footer posed an additional problem; without trenching the crew couldn't bring in new pile.

They used their mini-crane to raise the RC-30's bucket attachment and lower a DAVCO backhoe attachment to replace it. For hours the Whatcom crew dug up rip-rap, raising it and then placing the debris on solid ground before high tide returned. As the tide rose, the RC-30 was working in essentially 2 feet of water.

Through the night and into the next day, rip-rap removal continued.

"We weren't worried about getting wet. We were worried about losing our ASV to the sea," Diller recalled with a smile. "I had a spotter at the front and back of the ASV as it dug out the rip rap and made a narrow trench for sheet pile. As we pulled more rip-rap out, the machine had to crawl backward through more muck and more water. It was dangerous for the operator and not to mention, we had a structure teetering above us."

After navigating in and out of the tides, all of the debris was cleared and safely placed on high ground. Next, the crew dug potholes to place dead-man anchors far upland using the ASV and the DAVCO attachment. Finally, Diller's crew had everything cleared and the dead men in place with tiebacks waiting to be connected. They were now able to drive in the new sheet piles for the seawall.

For 48 hours they drove piles for the new seawall. The crew secured it with tiebacks and craned the RC-30 out of the barely maneuverable area.

"The seawall was in place to stop the waves from crashing and eroding the bank further, but Mother Nature still hadn't had enough," said Diller.

Filling the Void

The crew still needed to place pea gravel in the void between the bank and the seawall to prevent further eroding. The terrain was soaking wet with a narrow route. The RC-30 drove over saturated ground from dump truck to seawall, placing pea gravel into the void. By the end the ASV was pushing pea gravel under the house with the DAVCO attachment and riding on top of the seawall cap with one track on the cap and one on the gravel.

"We probably made 200 laps to get all the pea gravel into place. The property owners were surprised to see we weren't doing any damage to the ground with our machine," Diller said. "Then I told them we used biodiesel in it, too."

Whatcom's immediate response helped the property owner recover what could have been a total loss. This circumstance posed unique challenges that Diller's cowboys were able to manage because they had the proper equipment, experience and foresight.

As the construction landscape changes, it is important to be versatile and prepared for the unexpected. Diller's crew will continue to build, repair and succeed in such projects that demand immediate reaction like that of the 2007 flood. They are able to perform efficiently in emergency response situations because they have the proper knowledge and equipment giving them an edge in a competitive industry.

Author Information
Kip Lindman is an associate with Carmichael Lynch Spong, Minneapolis.