Performance evaluation of backwater valves to mitigate basement flooding from sewer surcharge events

由于下水道堵塞而导致的地下室洪水是家庭保险索赔最昂贵的来源。安大略省最近发生的洪灾事件(如2005年和2013年多伦多的洪灾)已导致数亿美元的财产损失，原因是下水道备份到房主的地下室。地下室洪水事件的发生受到许多因素的影响，包括：气候变化导致的极端降水事件的规模和频率增加，以及老化、有缺陷和设计不足的下水道基础设施。今天市场上可用的一种场侧技术是回水阀，它可以安装在个人住宅的下水道支管上，以防止下水道通过地下室的排水沟堵塞。尽管回水阀有很多好处，但关于回水阀的性能和适用性仍存在许多不确定性。 考虑到这一点，本研究的目标是评估各种回水阀模型在下水道超载事件下的性能。这项研究是与行业合作伙伴减少灾难性损失研究所(ICLR)合作进行的，将利用西安大略大学更美好家园保险研究实验室(IRLBH)进行全面的实验室测试。实验测试将确定阀门恶化的特征，找出阀门故障的原因，评估回水阀门的寿命，并确定单个家庭管道和下水道横向配置的最佳阀门型号。结果将提供：i)改进安装回水阀的市政指导方针；ii)向保险业提供技术建议，以制定适当的政策；iii)为房主提供更多信息，以减少在下水道附加费事件期间地下室洪水造成的水损害风险。

Basement flooding due to sewer back-up is the most expensive source of home insurance claims. Recent flooding events in Ontario (such as the 2005 and 2013 floods in Toronto) have resulted in hundreds of millions of dollars in property damages due to sewer backups into homeowners' basements. Occurrences of basement flooding events are influenced by numerous factors, including: an increase in magnitude and frequency of extreme precipitation events due to climate change, and aging, defective and under-designed sewer infrastructure. One lot-side technology available in the marketplace today is the backwater valve which can be installed on sewer laterals in individual homes to prevent sewer back-up through basement drains. Despite its benefits, numerous uncertainties exist regarding the performance and suitability of backwater valves. Considering this, the goal of this research is to evaluate the performance of a variety of backwater valve models subjected to sewer surcharge events. Conducted in collaboration with industry-partner the Institute for Catastrophic Loss Reduction (ICLR), this research will be conducted through full-scale laboratory testing using the Insurance Research Lab for Better Homes (IRLBH) at the University of Western Ontario. The experimental testing will characterize valve deterioration, identify causes of valve failure, evaluate the lifespan of backwater valves, and determine optimal valve models for individual home plumbing and sewer lateral configuration. Results will provide: i) guidance to improve municipal guidelines for the installation of backwater valves; ii) technical recommendations to the insurance industry to develop appropriate policy; and iii) greater information to homeowners to reduce risk of water damage due to basement flooding during sewer surcharge events.