Local Civil Engineers Explore Ways to Protect Infrastructure from Climate Change Impacts

posted in: May 2015 | 0

“I can’t tell you how many ulcers I get in a matter of hours when there’s a possibility I could lose 30 pump stations in one event,” said Timothy Steinberger, the former director of Honolulu’s Department of Environmental Services.

The cause of Steinberger’s ulcers was the city’s wastewater system, much of which is located along coastlines or in areas vulnerable to flooding.

With climate change and associated sea level rise, some of O`ahu’s most critical infrastructure —Honolulu harbor, the Honolulu International Airport, sewage treatment plants and pumping stations, and electrical and transportation systems —are vulnerable to flooding.

A recent modeling study by University of Hawai`i scientists on the combined threat of a 1-meter rise in sea level and tsunami or hurricane inundation found that $34.8 billion, or 80 percent, of the economy located along Honolulu’s urban core may be affected by the combined hazard.

At a one-day infrastructure sustainability seminar in downtown Honolulu last month, dozens of local engineers discussed the need to design projects to weather the impacts of climate change.

The seminar, sponsored by the Hawai`i chapter of the American Society of Civil Engineers and local law firm Carlsmith Ball, LLP, featured panel discussions with local engineers and planners, including Steinberger, and a series of talks by William Wallace, co-creator of the Envision rating system, which, similar to LEED, is aimed at producing sustainable projects.

“There are a lot of things that are happening that are pretty scary,”Wallace said. Along with anticipated changes in storm intensity and temperature, new engineering solutions will be needed as  engineers become less able to trust the “body of knowledge of how things have historically operated,”he said.

Although researchers globally have been trying to characterize anticipated, local impacts of climate change, Wallace stressed that infrastructure projects must account for unforeseen conditions.

“There may be tipping points beyond which we don’t know what is going to happen,”he said.

Contingency Planning

Whether the concern is temperature change or sea level rise, engineers have three ways they can incorporate sustainability into a project, Wallace said. They can: 1) design it to be more robust to account for unusual or extreme circumstances; 2) identify an adaptation strategy so that when conditions change beyond a certain point, “we’ll adapt to another level;” and 3) design so that if the project is, for example, damaged by a storm, operations can recover quickly.

As an example, he described efforts by city of Olympia, Washington, to design a suite of engineering solutions to be incrementally implemented as sea levels rise. They include tide gates, various kinds of barriers, outfalls, and pump stations, among other things.

Like Honolulu, much of Olympia’s critical infrastructure sits in low-lying areas. And with the city located at the base of Puget Sound, those areas are particularly vulnerable to flooding.

Research has shown that even a small rise in sea level greatly increases the probability of flooding in Olympia’s downtown area. Lands identified in the past as being vulnerable to impacts of a 100-year flood would be affected every 18 years if sea level were to rise just half a foot, according to a 2011 City of Olympia Engineered Response to Sea Level Rise technical report.

The report specifies the location, type, and cost of structures that need to be installed with each incremental change in sea level. For example, the report recommends that flood barriers be installed at certain locations on the west facing shoreline of the city’s peninsula before sea level rises a quarter of a foot, and along the east facing shoreline before it rises half a foot. If sea level rises by 50 inches, the report recommends that the barriers be increased in height.

The cost for the various barriers needed to manage a rise in sea level of one foot was estimated at about $8.5 million. With a four-foot, two-inch rise, the cost grows to $13.6 million. Additional costs include $30 million for a 500 cubic-foot-per-second pump station, and $7.5 million for two smaller pump stations.

Whether or not such projects will receive full funding remains to be seen, but Wallace said the city has already designed a boardwalk with adaptability in mind. It was designed to last 25 years rather than the standard 50 years, and is both flexible and saltwater resistant.

He then asked seminar attendees, “Is anyone doing anything that deals with adaptation in this way? Are we all linear?”

“Uh-oh,”he said, on seeing not a single hand raised.

Granted, civil engineers are “at the bottom of the food chain”and, generally, get told what to do, he said.

“We’re trying to give you that information so you can knock on the project manager’s door and, for example, convince him or her not to put a road right next to the shoreline,”he said.

He admitted that education may not be enough in some cases.

“There is high resistance to change by owners and operators of existing systems that have a stake in the status quo,”he said.

Regulators here may also still be struggling with how to incorporate the sea level rise and coastal inundation research released over the past year or so. Modeling has shown that in Honolulu and Kaka`ako, flooding as deep as 1.5 meters could reach Beretania Street, located just mauka of the core of downtown Honolulu. In the back of the Mapunapuna industrial area, at Pearl Harbor, Waikiki, and the airport’s reef runway, flooding could be as deep as two meters.

The modeling also identified, on a block-by-block basis, which parts of the upcoming rail system are vulnerable to inundation hazards.

At last year’s Ocean Sciences conference in Waikiki, University of Hawai`i’s Dolan Eversole, who participated in the sea level modeling work unveiled last year, said he saw some “very surprised looks” when he presented the information to local managers.

They were not sure what to do and kept asking him, “So now what?”he said.

Last year, the state Legislature established a committee to complete a sea level rise vulnerability and adaptation report by December 2017. Whether it will identify specific actions needed to protect infrastructure remains to be seen.

O`ahu’s broader planning documents —the General Plan and the Sustainable Community Plans for the island’s different regions —generally have not factored in climate change impacts, according to Steinberger, who now works at HDR, a private engineering company.

“A lot of the plans don’t even take into account the possibility of sea level rise. …Projects going out right now don’t take into account sea level rise. Plans for wastewater components don’t even take into account tsunami or hurricane inundation,”he said.

“When you look at the General Plan, it does need to be redone and take into account what is happening in the world,”he added. A draft general plan is expected to be released this fall.

When it comes to getting funds for sustainability projects, Steinberger said the city council often argues they’re unaffordable and questions whether they’re really necessary.

In planning for a sustainable future, Steinberger said, “you’ve got to fight for these things all the time. Unfortunately, we lose a lot of the time. That’s what gives you a lot of grey hair.”

Effecting Change

When asked how to generate the political will to make the necessary infrastructural changes, Wallace admitted that it’s difficult given the costs involved and the “nitwits” in certain governmental positions who are still declaring that climate change isn’t happening.

He even criticized the ASCE, stating that its greenhouse gas emissions policy is “full of crap.”

“It’s still hemming and hawing,”he said, despite the society’s code of ethics that calls for engineers to take into account public health, safety and welfare. Ignoring or minimizing climate change is an ethical violation of “what our duty is as engineers.”

He suggested that engineers need to start telling politicians things they don’t want to hear.

Ian Sandison, an attorney with Carlsmith Ball and a former engineer, challenged local engineers to start developing a set of criteria for sustainable infrastructure that can find its way into specifications issued by agencies such as the U.S. Army Corps of Engineers and the Honolulu Department of Planning and Permitting.

“There is nobody that doesn’t say, ‘My project is sustainable.’There is almost no agreement on what that word means,”said Sandison.

Simply discussing sustainability in a project’s environmental impacts statement didn’t seem adequate to him. Those statements “just talk about impacts, but don’t really have a metric,” he said.

“How can we provide a legal incentive for a more sustainable project rather than a less sustainable project?”he asked. Absent new “sustainability”metrics, on a “very micro level,”engineers can adopt the standards in the Envision rating system, he added.

“Put it in your specs and make it work. All of you can do it. You don’t need legislation. It’s within your power to make a significant change here,”he said.

Teresa Dawson

For Further Reading

“City of Olympia Engineered Response to Sea Level Rise,” by Coast & Harbor Engineering: http://olympiawa.gov/community/sustainability/~/media/Files/PublicWorks/Sustainability/Sea%20Level%20Rise%20Response%20Technical%20Report.ashx

Combined sea level rise inundation risk map for urban Honolulu:  http://oos.soest.hawaii.edu/pacioos/projects/slr/

“Doubling of coastal erosion under rising sea level by mid-century in Hawai’i.” Natural Hazards Tiffany R. Anderson, Charles H. Fletcher, Matthew M. Barbee, L. Neil Frazer & Bradley M. Romine (2015). : http://link.springer.com/article/10.1007%2Fs11069-015-1698-6

 

Emergency repairs of coastal infrastructure are expensive and disruptive. To repair this 610-foot stretch of Kamehameha Highway in Ka`a`awa — part of which crumbled onto the beach earlier this year — the state Department of Transportation has set aside $8 million. As of last month, the department was still considering whether to close the road entirely or partially, and whether work would occur 24/7 or only during the day. The highway is the only route in or out for the thousands of residents along Oahu's windward coast. Construction is expected to begin this month and end in August. Photo: Hawaii Department of Transportation
Emergency repairs of coastal infrastructure are expensive and disruptive. To repair this 610-foot stretch of Kamehameha Highway in Ka`a`awa — part of which crumbled onto the beach earlier this year — the state Department of Transportation has set aside $8 million. As of last month, the department was still considering whether to close the road entirely or partially, and whether work would occur 24/7 or only during the day. The highway is the only route in or out for the thousands of residents along Oahu’s windward coast. Construction is expected to begin this month and end in August. Photo: Hawaii Department of Transportation

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