By Romanda Walker (St. Louis District) and Pete Pierce (Headquarters U.S. Army Corps of Engineers)
Since the creation of its Levee Safety Program in 2006, the U.S. Army Corps of Engineers has made great strides in the rapidly evolving field of levee safety.
One of the most recent and important levee safety milestones is the public release of the National Levee Database (NLD), a living, dynamic information source that provides visualization and search capability for the first time on the location and condition of levee systems nationwide.
But before the recent public fielding, in 2006 USACE began to develop the NLD model. The Water Resources Development Act of 2007 complemented this effort, expanding the Corps’ authorities to collect information for all levees in the nation for the database. Since then, USACE has refined the complex database, performed detailed surveys of the levees in the USACE program, and worked with stakeholders to develop the best strategy to collect data on the remaining estimated 100,000 miles of levees in the nation.
Currently, the NLD includes detailed information on the levee systems within the USACE Levee Safety Program. Included in the USACE program are about 14,700 miles of levees, which includes:
- Levees operated and maintained by USACE.
- Federally authorized or built levee systems, but locally operated and maintained.
- Locally built, operated, and maintained levees that have qualified to be in the federal program under Public Law 84-99 (Rehabilitation and Inspection Program).
USACE continues to work with the Federal Emergency Management Agency (FEMA) to include those levees identified in its Mid-term Levee Inventory.
The database includes detailed information on levees and floodwalls that is relevant to flood fighting, design, construction, operation, maintenance, repair, and inspection. The database serves as the single national source of levee information to facilitate risk communication and links data from public sources such as weather data from the National Weather Service, physical data from the U.S. Geological Survey, hazards data from FEMA, and critical infrastructure data from the Department of Homeland Security.
The NLD is intended for use by:
- Federal, state, tribal, regional, and local agencies.
- Levee system sponsors, operators, and maintainers.
- Emergency managers.
- The public.
For example, emergency managers recently used the NLD to help inform 2011 flood fighting activities. Residents will be able to view the levees in their neighborhoods, which will allow them to make better-informed decisions about their safety. The NLD is currently available at https://nld.usace.army.mil
and will be the nation’s single source of information for levees.
Another important Levee Safety Program milestone will be the completion of initial periodic inspections for the federal levees within the USACE Levee Safety Program, a type of inspection never performed on levees before. Periodic inspections for levees, modeled after the Dam Safety Program inspections, are a more detailed, comprehensive and consistent evaluation of the condition of the levee system and is conducted by a multidisciplinary team, led by a professional engineer. Activities under the periodic inspection include:
- Evaluation of routine inspection items.
- Proper operation and maintenance verification.
- Evaluation of operational adequacy, structural stability, and safety of the system.
- Compares current design and construction criteria with those in place when the levee was built.
“Periodic inspections offer a more comprehensive look into levee systems and provide additional data to help make risk informed decisions about flood risk management,” said Steve Stockton, director of Civil Works.
The American Recovery and Reinvestment Act of 2009 (ARRA) presented an opportunity to leverage stimulating the economy through the use of the private sector contractors to accomplish these periodic inspections, and thus helping to further obtain much-needed information about the levee infrastructure throughout the nation. With $90 million through ARRA, late 2012 will mark the completion of the first round of USACE periodic inspections for 60 percent of the federally authorized levees in the USACE program.
An advantage of conducting these initial inspections through ARRA is that the private-sector firms performing this work are providing USACE an independent and consistent assessment of the condition of these levees.
“We’re finding consistent deficiencies across the U.S., especially with unwanted vegetation and encroachments,” said Jamie McVicker, the USACE periodic inspection project manager from St. Louis District. “We’re concerned not only with the integrity of the levee but also accessibility during flood fighting. You don’t want vegetation to impede bringing vehicles in to fight a flood. We also have excessive animal burrows, deficiencies with drainage and closure structures and erosion issues. Pump station deficiencies, sometimes contributing to safety concerns, are also routinely documented.”
USACE is also continuing to further advance its overall Levee Safety Program, and has initiated an effort to take multiple pieces of levee safety guidance and procedures and consolidate them into a single comprehensive policy, or Engineer Circular (EC), that will guide the program. While this may seem like a rather routine undertaking, in reality it is not. Early in the scoping process for the EC, the levee safety policy and procedures team (LSPPT) that will create the EC realized that numerous stakeholders and partners participate with USACE to manage levee systems. It followed, then, that stakeholder and sponsor feedback would be helpful in shaping the program’s policy guidance framework.
“Responsibility for assessing, characterizing and communicating the risks associated with levee systems has to be shared among federal, state, local, and tribal partners,” said Eric Halpin, USACE special assistant for dam and levee safety. “We cannot do this alone. Our partners and stakeholders are critical to making sure people depending upon levee systems know their risk, know their role and take action.”
In late 2010 and throughout 2011, the LSPPT embarked upon extensive stakeholder involvement, soliciting input from its various internal communities of practice while also gathering input from levee system sponsors and stakeholders external to USACE. The LSPPT also hosted webinars in December 2010, and February and March 2011. Then the team followed up with two, three-day workshops in May and June. Each of the webinars built upon the previous and, while the workshop agendas were the same, USACE held them in different geographical locations.
Currently the LSPPT is reviewing comments and drafting the chapters for the Levee Safety Program Engineer Circular. Once the draft EC is complete, USACE plans to host another series of outreach activities for sponsors and stakeholders.
USACE anticipates the upcoming year to be equally action-packed as it continues to move the program to higher levels using stakeholder and partner involvement, and by leveraging more state-of-the practice improvements, such as the NLD.