PROBLEM
Nearshore nourishment is a form of strategic sediment placement that can reduce waves, use natural forces to sort coarse sand from fine material, and transport sand onshore. It is a common strategy to beneficially use sediment from dredging projects that keeps sediment in the system and potentially reduces costs. However, questions exist about how quickly sediment placed in the nearshore will move and the direction it will travel. Time and budget restrictions often prevent the use of robust numerical models to study these projects.
$5 COST SAVINGS PER PROJECT
THOUSAND (APPROX.)
$110
COST SAVINGS PER THOUSAND SEASON (APPROX.) IN THE COLUMBIA RIVER
SOLUTION
To address key regulatory and stakeholder questions, ERDC created the Sediment Mobility Tool (SMT) to assist planners and engineers in rapidly identifying and evaluating potential nearshore placement sites. The tool was designed to save both time and money; it is also an effective communication tool to garner support of regulators and stakeholders for nearshore nourishment projects.
IMPACT
20
The SMT saves on a project-by-project basis by completing in five minutes what previously took a coastal engineer a week, saving approximately $5,000 per project. It also provides guidance for nearshore nourishment placement, which can save money while keeping sediment in the system for healthier and more resilient coastlines. For a recent project at the mouth of the Columbia River, placing sediment in the nearshore led to approximately $110,000 in cost savings per season compared with the deepwater placement site, with the added value of keeping sediment in the littoral system.
