Report: Sandy was a wake-up call we'd better heed

A new Army Corps of Engineers report warns that unless coastal residents and state and local leaders rethink their approach to shoreline development, the next big storm will be equal to or worse than Superstorm Sandy with its $65 billion in losses, 159 U.S. deaths and 650,000 homes damaged or destroyed.

The report, two years in the making, points to a future where storms are more devastating because of climate change and sea-level rise and highlights the vulnerability of critical infrastructure like roads, bridges, power and water supplies and communication networks.

And it will get worse because of climate change and rising sea levels. Add to that, an aging, more vulnerable population throughout the study area.

Among the key findings: Flood risk is already increasing; better land use planning is needed, especially in flood-prone areas; and the use of natural and nature-based approaches should be used to minimize or reduce flood risk when development can't be avoided.

"The report provides a framework for communities that will arm them for the reality of future extreme weather," said Jo-Ellen Darcy, the assistant secretary of the Army for Civil Works.

For Delaware, the report points to two high-risk areas: the shoreline of Delaware River and Bay and the resort-areas' Inland Bays.

It was the bay sides of Fenwick Island, South Bethany Beach, Bethany Beach and Dewey Beach that suffered among the worst flood damage from Superstorm Sandy. Days after the storm, residents were still shoveling mud, ripping out soggy drywall and discarding furniture and appliances that were ruined by flooding.

Even undeveloped areas suffered. At Prime Hook National Wildlife Refuge, federal officials will spend an estimated $40 million to plug large areas where Delaware Bay surged into the adjacent marsh and cut new inlets. They will alter the marsh hydrology in an attempt to make the area more resilient in future storms.

And even though the storm made landfall near Atlantic City and spared Delaware far worse damage, lower Delaware had heavy rainfall and more than 45,000 customers statewide were without power.

Grim realities

"Hurricane Sandy brought to light the reality that coastal storms are intensifying and that sea-level change and climate change will only heighten the vulnerability of coastal communities," said Brig. Gen. Kent D. Savre, commanding general of the corps' North Atlantic Division.

The corps' assessment included a range of future extreme water-level forecasts, based on assumptions about climate change and sea-level rise. Even the moderate increase assumptions gave rise to an expectation that, in a century, storms will push water at Lewes more than 1 foot higher at least once a year than was seen during the height of Superstorm Sandy, the second-highest level on record at Lewes Breakwater Harbor tide gauge.

Worst-case sea-level rise assumptions could push water along the Lewes shoreline every year more than 5 feet higher than was seen during Sandy. In one most-severe set of calculations, Lewes would have a 1-in-100 chance every year for storm-driven tides up 8.5 feet higher than Sandy's formidable mark.

Even moderate corps estimates of sea levels in the coming century show a likelihood of storm tides every year at Lewes more than a foot higher than Sandy, with a 1-in-10 chance every year for a storm with tides topping out at 1.8 feet higher than Sandy.

Similar and increasingly extreme future high-water risks would occur all along Delaware Bay and Delaware River shorelines and well inland.

Jeffrey M. Bross, chairman of Delaware-based Duffield Associates, a regional engineering firm, said the corps report was "fairly draconian" in its predictions, but an important part of public responses.

"I'm not sure I subscribe to the high sea-level rise scenario, but in the work we do, we feel it's prudent to at least anticipate something in the low to moderate range," Bross said.

"The parade of horribles"

Maya van Rossum, who directs the regional Delaware Riverkeeper conservation group, said risks to areas along the Delaware River and Bay became clear decades ago.

"The parade of horribles as to who's going to get hit — to me, that's confirmation of everything we've been hearing along the way," van Rossum said.

"The question is: What are they suggesting we do about it? That and making sure that they're not suggesting sea walls and infrastructure that are simply doing things that are going to make it worse for other people."

Preparations need to coincide with efforts to reduce greenhouse gas emissions associated with rising global temperatures, climate change and sea-level rise, van Rossum said.

"Part and parcel with that, we need to accept the reality that we have made some very poor choices about where and how we developed. It's time to pull back from the water's edge and move our families and communities up the hill, out of the flood plain, out of the flood zone so they can be permanently protected."

The corps report acknowledged as much, saying coastal communities "face tough choices as they adapt local land-use patterns while striving to preserve community values and economic vitality."

"In some cases, this may mean that, just as ecosystems migrate and change functions, human systems may have to relocate in a responsible manner to sustain their economic viability and social resilience," the report said in a preface.

The report recommends communities identify their acceptable level of risk and plan for the long term.

Dollar signs

Depending on the approach, costs are potentially huge.

Construction of storm-surge barriers to protect flood-prone areas of the Christina River and Indian River Inlet, the corps report estimated, would cost a combined $2.57 billion, or an average annual combined cost of about $187 million. The barrier along the river would need to be about 1,250 feet long and 55 feet above the lowest water level, while the inlet height would have to be 800 feet long and more than 86 feet above the low-water benchmark.

All along the coast, huge numbers of homes and public resources are at risk.

The Bureau of Labor Statistics recently released a report showing that more than 25,500 people work in more than 1,440 establishments inside Delaware's current flood zones — areas of hazard that reflect already outdated storm-surge estimates and boundaries far too small.

About $227.5 million in quarterly wages are at risk inside the areas statewide, with the largest share — more than 17,000 jobs and $132.8 million in quarterly wages — in Sussex County.

Superstorm Sandy proved both the risk and potential cost of coastal storms and extreme water levels along the Atlantic, the corps pointed out, including to critical infrastructure like nuclear power plants.

Salem Unit 1 at the Salem/Hope Creek nuclear complex was one of eight reactors on the East Coast affected by the storm, with Salem offline for seven days afterward. Salem Unit 2 was offline for refueling at the time, but four of six circulating water pumps in its companion Unit 1 were unavailable as a result of the storm, and debris and waves clogged the operation's critical water intake screens.

A switching station at the plant, considered "non-vital," was lost because of water intrusion, and several buildings lost power, with telephones, the plant's intranet and a weather station also knocked offline.

The adjacent Delaware River rose to 99.5 feet, more than 10 feet above normal. It was just below ground level at the plant, although the Salem units were designed for flooding 20 feet above the plant's ground level, with critical operating intakes 6 feet to 14 feet above that.

State environmental chief David Small said neither he nor his staff have reviewed the lengthy corps report, released Wednesday, but he believes it will be an important tool for providing a blueprint for future decisions, reducing future risk, and setting up a network where state, federal and local officials can better manage assets, such as funding across agencies to get better results.

And, Small said, it will further the discussion that has already started in Delaware about the impacts of both climate change and sea-level rise.

"There's a lot to talk about," he said.

Other options

Delaware's sea-level issues go beyond the coastal areas that the corps report addresses, Small said. There are also concerns about municipalities like Laurel and Seaford, where flooding has already been a significant problem during heavy, nonhurricane-related, rains.

The corps assessment takes a close look at some of the vulnerabilities along the Delaware River and Bay and Rehoboth, Indian River and Little Assawoman bays.

But Amy Guise, chief of the command center for the North Atlantic Coast Comprehensive Study, said while the report gives suggestions, they are designed to be broad. She said every community has to deal with future flood risk based on the local issues and what they can afford do.

Less daunting options in terms of cost for Delaware Bay communities include early flood warnings and natural storm protection such as widened beaches, more robust dunes and natural or living shorelines.

Already, Chris Bason, executive director of the Center for the Inland Bays, is thinking toward the future.

"It's on my to-do list to find a new location for the center," he said.

The center is near the Indian River Inlet Coast Guard Station and overlooks both the inlet and Indian River Bay.

Bason said when he's out driving around the inland bays, he's never far from the flood potential.

"I think about how many bridges we're going to need."