Maintenance of navigation channels in shelf seas with tidal sand waves usually requires repeated dredging operations. Optimizing these interventions is a difficult task, particularly complicated by the nonlinear morphodynamics of sand wave recovery after dredging. Here we present a process-based model study, incorporating different strategies of dredging in an existing nonlinear sand wave model. We consider ‘topping’ (removing sand from crest) and ‘swiping’ (same, but now placing it in the troughs), for a range of dredging depths. Starting point is a fully developed sand wave or sand wave field, as simulated in the model. Results indicate that sand wave recovery is slowest after swiping. Also, larger dredging volumes imply longer recovery times. Next, we study the maintenance intervals and (cumulative) dredging volumes resulting from adopting a typical temporal strategy: swipe to a prescribed dredging depth, as soon as the recovering sand wave crests have reached a critical depth. Maintenance intervals are found to depend on the dredging depth and, importantly, to vary over time, as well. This last result shows that sand wave recovery depends not only on height, but also on its shape, emphasizing the limitations of existing, empirical (Landau-type of) models based on amplitude (or height) only.

在潮汐沙波的架子海中维护航行通道通常需要反复进行挖泥操作。优化这些干预措施是一项艰巨的任务，特别是由于疏after后砂波恢复的非线性形态动力学使情况特别复杂。在这里，我们提出了一个基于过程的模型研究，在现有的非线性砂波模型中纳入了不同的挖泥策略。我们考虑在一定的挖泥深度范围内进行“打顶”（从波峰上去除沙子）和“打滑”（相同，但现在将其放入槽中）。起点是模型中模拟的充分发展的沙波或沙波场。结果表明，刷卡后沙波恢复最慢。同样，较大的挖泥量意味着更长的恢复时间。下一个，我们研究了采用典型的时间策略所产生的维护间隔和（累积）疏volumes量：一旦恢复的沙波峰达到临界深度，就滑动至指定的疏depth深度。发现维护间隔取决于挖泥深度，重要的是，维护间隔也会随时间而变化。最后的结果表明，沙波的恢复不仅取决于高度，还取决于其形状，强调了仅基于振幅（或高度）的现有经验模型（Landau型）的局限性。