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

下水道堵塞导致的地下室淹水是家庭保险索赔中最昂贵的原因。安大略省最近发生的洪水事件（如2005年和2013年多伦多的洪水）造成了数亿美元的财产损失，原因是房主的地下室下水道堵塞。地下室洪水事件的发生受到许多因素的影响，包括：由于气候变化，极端降水事件的强度和频率增加，以及下水道基础设施老化、有缺陷和设计不足。目前市场上可用的一种场地侧技术是回水阀，它可以安装在个人家庭的下水道横向上，以防止通过地下室排水管堵塞下水道。尽管有很多优点，但是关于回水阀的性能和适用性存在许多不确定性。

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.