ABSTRACT Unpaved, or unbound aggregate, roads are thought to be one of the largest anthropogenic sources of fine sediments in the stream channels of small watersheds. Sedimentation can reduce water quality in streams negatively impacting aquatic habitat as well as being a detriment to municipal drinking water sources. Even during periods of low-volume use roads can be a chronic source of fine sediment. Legacy roads may degrade stream water quality more than newly built roads as they were constructed before modern best management practices. This study measured the production of sediment from the road surface of a legacy road system within a small watershed using controlled precipitation experiments to determine the mass of sediment that roads could produce during one storm event. Sediment production was not related to road slope or strength as measured by Clegg hammer. The production of sediment from the road surface increased 95% on average with wet traffic use. Using an estimated road and stream connectivity of 50%, surface runoff from the roads in Middle Creek watershed could account for 16% of the total sediment yield from the watershed during a small summer storm event. Compacted tire tracks were utilized as flow paths during runoff experiments, emphasizing the importance of continual maintenance and best management practices. This study highlights the need to disconnect unbound aggregate roads from stream channels in order to prevent negative water quality impacts associated with sedimentation.

中文翻译：

---

美国俄亥俄州东南部未铺砌的旧道路运行表面的沉积物生产

摘要 未铺砌或未结合的聚合体道路被认为是小流域河道中细小沉积物的最大人为来源之一。沉积物会降低溪流中的水质，对水生栖息地产生负面影响，并损害市政饮用水源。即使在低流量使用期间，道路也可能是细泥沙的长期来源。与新建道路相比，传统道路可能会更严重地降低河流水质，因为它们是在现代最佳管理实践之前建造的。这项研究使用受控降水实验测量了小流域内旧道路系统路面沉积物的产生，以确定道路在一次风暴事件中可能产生的沉积物质量。沉积物的产生与 Clegg 锤测量的道路坡度或强度无关。湿地交通使路面产生的泥沙平均增加 95%。使用估计的 50% 的道路和河流连通性，中溪流域道路的地表径流在夏季小型风暴事件期间可能占流域总沉积物产量的 16%。在径流实验期间，压实的轮胎轨道被用作流动路径，强调了持续维护和最佳管理实践的重要性。本研究强调需要将未绑定的聚合道路与河道断开，以防止与沉积相关的负面水质影响。使用估计的 50% 的道路和河流连通性，中溪流域道路的地表径流在夏季小型风暴事件期间可能占流域总沉积物产量的 16%。在径流实验期间，压实的轮胎轨道被用作流动路径，强调了持续维护和最佳管理实践的重要性。本研究强调需要将未绑定的聚合道路与河道断开，以防止与沉积相关的负面水质影响。使用估计的 50% 的道路和河流连通性，中溪流域道路的地表径流在夏季小型风暴事件期间可能占流域总沉积物产量的 16%。在径流实验期间，压实的轮胎轨道被用作流动路径，强调了持续维护和最佳管理实践的重要性。本研究强调需要将未绑定的聚合道路与河道断开，以防止与沉积相关的负面水质影响。强调持续维护和最佳管理实践的重要性。本研究强调需要将未绑定的聚合道路与河道断开，以防止与沉积相关的负面水质影响。强调持续维护和最佳管理实践的重要性。本研究强调需要将未绑定的聚合道路与河道断开，以防止与沉积相关的负面水质影响。