When midwestern floodwaters recently destroyed bridges and washed out 42 wastewater treatment plants, the heart of the nation felt the sting of an ongoing infrastructure challenge. More frequent and stronger weather events threaten infrastructure sustainability, forcing public budgets into cycles of repair and rebuild.
Contractors are on the leading edge of this challenge, tasked with providing sustainable solutions that don’t break the bank. Not surprisingly, research shows there is a big return on investment when infrastructure projects get built to a standard higher than many existing codes. However, it’s not about over-building, but smarter building.
Smart Investments = Create Big Returns
There is a lot at stake for public entities in stemming the total effects of severe weather on public investments. An independent study found that for every $3.5 billion spent mitigating the consequences of hurricanes, floods, and earthquakes, society would save $14 billion.
In the recent follow-up study, Natural Hazard Mitigation: 2018 Interim Report, the rewards of federal mitigation program grants returned a benefit of six dollars for every dollar invested. Meanwhile, adopting model codes for new construction returned a benefit of four dollars for every dollar invested. Research proves communities that consistently met newer codes improved infrastructure resilience.
Research proves communities that consistently met newer codes improved infrastructure resilience. They also added 30,000 jobs to the construction materials industry as well as increased domestic construction material use for each year of new construction. Even though public funding to mitigate natural hazards has dropped in recent years, contractors who understand the problems and solutions to infrastructure sustainability can still find opportunities in this market.
Build It Once
It’s obviously much cheaper to build a wastewater treatment facility or a bridge sustainably and then simply watch while it lasts through multiple extreme weather events. Especially, if it doesn’t necessitate repairing and rebuilding afterwards. And, exceeding the minimum code requirements for new public construction can often make a big difference in sustainability.
What about the already existing public infrastructure, though? What’s possible in changing the outcomes after severe natural events, and what are the benefits? The following examples tell the story:
Move It, Or Lose It
Contractors can often harden infrastructure by moving equipment out of the floodplain. For instance, using a federal grant from the Economic Adjustment Assistance program, Portsmouth, Virginia garnered a $112 million benefit to its wastewater treatment plant by spending $11.6 million in construction. In effect, the city saved $9.70 for every dollar spent when it relocated the electrical equipment for its Lake Kirby water treatment plant. What contractors did was to move the equipment from one foot below the 100-year floodplain to eight feet above the 500-year floodplain.
Columbus Junction, Iowa went a step further. It relocated an entire water treatment plant using the same grant assistance as Portsmouth. Contractors moved the plant from two feet below the 100-year floodplain to two feet higher than the 500-year floodplain. The result was $5.9 million in benefit for $4.6 million spent.
Often, the indirect costs of having an infrastructure facility down are overlooked in infrastructure considerations. For example, unworking bathrooms force business closures or increase spending on mitigation measures like renting portable toilets. Residents without water for showers and toilets are often forced to relocate temporarily.
These hidden costs all add to the savings when you build infrastructure more sustainably. Those are additional savings your public clients can use to justify sustainable infrastructure projects.
Bridging Severe Weather
When it comes to roadways and bridges, elevation can produce a sizeable return on investment. The folks in Iowa City, Iowa used an Economic Adjustment Assistance program grant to raise a road and reconstruct a bridge. In this case, the city got a $456 million benefit for $40.5 million in construction.
In 2014, New York State secured a FEMA grant to strengthen 20 bridges that had been at risk of having their foundations washed out in severe weather.
Making bridges more resistant to washout (scouring) greatly improves their sustainability. You can layer riprap, install cable-tied blocks, or install geobags. All of these improvements help to protect bridge abutments from washing out. For some bridges, like those in the New York case, engineers specified adding steel or concrete pile foundations.
Sometimes, you can change the activity of the water by increasing waterway openings to meet 100-year floodplain projections. Where ice forms in waterways, you can mitigate its effects by removing bridge piers causing ice dams that lead to localized flooding.
Most U.S. states report having moderate problems with bridge scouring. Some claim they’d have more scouring if it hadn’t been for countermeasures they’d used. Riprap was mentioned as the most widely used preventive measure, and it has a strong reputation for solving scouring problems.
Contractors who understand not just the challenges of severe weather on public infrastructure, but also the pros and cons of various solutions, position themselves as helpful resources to public entities. That little bit of extra knowledge can often tip a project in their direction.