Section Sanitary Engineering, Faculty of Civil Engineering and Geosciences, Delft University of Technology, PO Box 5048, 2600 GA, Delft, The Netherlands.
Section Sanitary Engineering, Faculty of Civil Engineering and Geosciences, Delft University of Technology, PO Box 5048, 2600 GA, Delft, The Netherlands; Deltares, PO Box 177, 2600 MH, Delft, The Netherlands.
Water Res. 2016 Jan 1;88:245-256. doi: 10.1016/j.watres.2015.10.021. Epub 2015 Oct 17.
Gully pots are essential assets designed to relief the downstream system by trapping solids and attached pollutants suspended in runoff. This study applied a methodology to develop a quantitative gully pot sedimentation and blockage model. To this end, sediment bed level time series from 300 gully pots, spanning 15 months, were collected. A generalised linear mixed modelling (GLMM) approach was applied to model and quantify the accumulation of solids in gully pots and to identify relevant physical and catchment properties that influence the complex trapping processes. Results show that the retaining efficiency decreases as sediment bed levels increase. Two typical silting evolutions were identified. Approximately 5% of all gully pots experienced progressive silting, eventually resulting in a blockage. The other gully pots show stabilising sediment bed levels. The depth of the sand trap, elapsed time since cleaning and the road type were identified to be the main properties discriminating progressive accumulation from stabilising sediment bed levels. Furthermore, sediment bed levels exhibit no residual spatial correlation, indicating that the vulnerability to a blockage is reduced as adjacent gully pots provide a form of redundancy. The findings may aid to improve maintenance strategies in order to safeguard the performance of gully pots.
雨水篦是一种重要的资产，通过捕获径流中悬浮的固体和附着的污染物来减轻下游系统的负担。本研究应用一种方法开发了一种定量的雨水篦泥沙淤积和堵塞模型。为此，收集了 300 个雨水篦的泥沙床层水平时间序列，跨度为 15 个月。应用广义线性混合模型（GLMM）方法对雨水篦中固体的积累进行建模和量化，并确定影响复杂捕获过程的相关物理和集水区特性。结果表明，随着泥沙床层水平的升高，截留效率降低。确定了两种典型的淤积演化。大约 5%的雨水篦经历了渐进式淤积，最终导致堵塞。其他雨水篦则表现出稳定的泥沙床层水平。沙坑的深度、上次清理后的时间和道路类型被确定为区分渐进式淤积和稳定泥沙床层水平的主要特性。此外，泥沙床层水平没有残留的空间相关性，这表明随着相邻雨水篦提供一种冗余形式，堵塞的脆弱性降低。这些发现可能有助于改进维护策略，以确保雨水篦的性能。
