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雨水控制用于道稳定性:专注于床材运输可以防止降解
S Towsif Khan1, T Wynn-Thompson2, D Sample3
1Water Resources Engineer, Center for Watershed Protection, Fulton, MD, USA.
Journal of environmental management
|January 13, 2025
概括
当前的雨水法规未能在城市开发后保护溪流道免受侵蚀. 为了保持通道的稳定性,需要其他设计,重点是沉积物运输,而不仅仅是流水量.
科学领域:
- 环境工程 环境工程
- 水文学的水文学
- 城市规划 城市规划
背景情况:
- 风暴控制措施 (SCM) 对于减轻城市化的水文影响至关重要.
- 现有的统一风暴水尺寸标准 (USSC) 有效地减少了不透气的地表流水,但无法充分保护通道的稳定性.
- 在美国11个州和哥伦比亚特区,USSC被广泛采用.
研究的目的:
- 评估两种替代性雨水法规在防止道侵蚀方面的有效性.
- 将基于USSC的设计与以形态为重点的SCM设计的性能进行比较.
- 评估不同雨水大小标准对沉积物运输和通道稳定性的影响.
主要方法:
- 一种校准的,连续的建模方法,集成风暴水管理模型 (SWMM) 和水文工程中心河流分析系统 (HEC-RAS).
- 一种三步方法:建立开发前条件,设计通道稳定的SCM,并通过连续模拟评估监管效率.
- 建模侧重于各种设计风暴条件下的沉积物运输和道形态.
主要成果:
- 基于USSC的SCM设计增加了沉积物运输的2至2.7倍,是常见设计风暴的开发前水平.
- 针对开发前沉积物运输的替代性SCM设计,减少了30-70%的峰值流量.
- 以形态学为重点的SCM设计成功地防止了尖端的形成,与基于水文目标的设计不同.
结论:
- 目前的USSC法规不足以保护城市化后的河流道免受侵蚀.
- 将通道形态和床材纳入SCM设计对于防止通道退化至关重要.
- 以沉积物运输为重点的替代性雨水管理策略对于可持续的城市发展是必要的.
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