Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology, SE-97187, Luleå, Sweden.
Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology, SE-97187, Luleå, Sweden.
J Environ Manage. 2023 Dec 15;348:119336. doi: 10.1016/j.jenvman.2023.119336. Epub 2023 Oct 18.
Gully pots (GPs) are ubiquitously used in urban catchments, to direct surface runoff into piped sewer systems, reduce the risk of sediment-induced pipe blockages and the loading of solids and associated contaminants on the receiving waters. Over time, the build-up of sediments in GPs will lead to impaired hydraulic performance, putting the urban catchment at risk of flooding. However, GP maintenance strategies lack both a robust evidence base and clear aims against which their effectiveness can be benchmarked. An improved understanding of the factors influencing long-term in-situ solids accumulation in GPs is required for further assessment and optimisation of the GP maintenance scheme. As a contribution to addressing these knowledge gaps, sediments from 27 GPs located in urban catchments associated with three street feature types (roundabout; crossing; straight road) and varied traffic intensities were collected on two occasions, representing two distinct seasonal accumulation periods. Parameters including GP fullness levels, particle size distribution (PSD), and solids mass accumulation rates were evaluated with regards to the impacts of seasonal activities, traffic conditions as well as configuration and dimension of GPs. The results indicate impacts of seasonal activities on solids accumulation rates were not consistent across all GPs, with the magnitude of the difference larger following winter-spring catchment practices. Additionally, synergistic impacts of seasonal activities and traffic conditions on PSD and solids accumulation rates were observed. For example, the winter road safety measures may enhance the impacts of the characteristic vehicle turning motions at roundabouts, contributing to the negative correlation identified between traffic intensities and solids accumulation rates. The overall exhibited large variations in sump fullness levels (4 %-73 %) and solids dry mass (0.5-51 kg) directly challenged the commonly adopted generalised GP maintenance frequency without taking the catchment-specific activities into consideration.
雨水口（GPs）广泛应用于城市集水区，将地表径流引导到管道污水系统中，降低泥沙引起的管道堵塞风险以及固体物质和相关污染物在受纳水体中的负荷。随着时间的推移，GPs 中的沉积物堆积会导致水力性能受损，使城市集水区面临洪水风险。然而，GP 维护策略既缺乏强大的证据基础，也缺乏明确的目标，无法据此衡量其有效性。为了进一步评估和优化 GP 维护方案，需要更好地了解影响 GPs 中固体物质长期原位积累的因素。为了填补这些知识空白，本研究两次从与三种街道特征类型（环岛；交叉口；直路）和不同交通强度相关的城市集水区的 27 个 GP 中收集沉积物，代表两个不同的季节性积累期。评估了 GP 饱满度水平、颗粒大小分布（PSD）和固体质量积累率等参数，以了解季节性活动、交通条件以及 GP 的配置和尺寸对其的影响。结果表明，季节性活动对所有 GP 中固体积累率的影响并不一致，冬季-春季集水区作业后差异幅度更大。此外，还观察到季节性活动和交通条件对 PSD 和固体积累率的协同影响。例如，冬季道路安全措施可能会增强环岛特征车辆转弯运动的影响，导致交通强度与固体积累率之间存在负相关关系。总而言之中，集水池的饱满度水平（4 %-73 %）和固体干质量（0.5-51 kg）变化很大，这直接挑战了普遍采用的通用 GP 维护频率，而没有考虑到集水区的具体活动。
