Mandatory Replacement of Sewer Laterals

In 2008, The City of Surrey took proactive action to combat the emerging, longer-term problem with private sewer connections by introducing a by-law to ensure better maintenance of private sewer laterals (sanitary and storm). As climate change contributes to increased intense rainfall events, excessive water flow can severely limit the capacity of existing sewer systems to serve expanded populations, generate sewer backups, flood basements, impose health risks, increase the operation and maintenance costs of treatment and pumping facilities, and lower groundwater levels leading to detrimental effects on water resources. A particular challenge for local governments involves confronting problems with sewer connections and laterals on private property that have the potential to cause damage to the overall community. Local authorities in Surrey, British Columbia, have come to learn that 30 to 70 percent of inflow and infiltration in sewer systems originates from private laterals. The City took early action to confront this problem with a by-law that introduced several triggers that would lead to the mandatory replacement of sewer laterals in Surrey. Central to the approach of the by-law was the focus on properties choosing to undergo significant renovation or redevelopment. The by-law used redevelopment valued at greater than $100,000 as a trigger for the assessment and potential replacement of private sewer laterals. This made the improvement of private sewer connections one element of a larger renewal process. Requiring all homeowners to change their sewer laterals would be impractical, but having property owners assess the state of their laterals during a time of significant investment in renewing their homes was an effective, proactive approach to this issue. The by-law has not been challenged since its implementation, but the City is looking to revise components of the by-law to provide an exemption for property owners required to conduct major unplanned renovations due to circumstances out of their control – extreme weather events for example.

Understanding and Assessing Impacts

Wet weather sanitary sewer overflows are typically the result of excessive amounts of rainwater inflow and groundwater infiltration entering the sanitary sewer system. Increased frequency and severity of rainfall events—a direct consequence of a changing climate—means both young and older communities are at risk of excessive inflows in their sewer systems. These inflows can occur when roof drain leaders, foundation drains and drainage catch basins are incorrectly connected to sanitary sewers instead of storm sewers. Further, cracks and loose joints in storm sewer laterals can lead to exfiltration into the sanitary system. As climate change makes this a more pressing issue across Canada, one of the challenges in confronting this problem is that losses resulting from excessive inflow and infiltration are frequently misidentified by the public to be exclusively the result of municipal infrastructure failure. In reality, as local officials in Surrey identified, 30 to 70 percent of inflow/infiltration originates from private sewer laterals. That is, problems with sewer connections and laterals on private property have the potential to cause damage to the community as a whole. While owners are responsible for repairing or replacing their sewer connection so no rainwater or groundwater enters the system, the City of Surrey found that a significant and growing volume of rainwater has been entering the sanitary sewer system through private connections. This posed a unique challenge to the local government in Surrey. They had to devise a proactive approach that would inspire private property owners to assess the state of their sewer laterals for the benefit of an entire community. Upon understanding the issue and the obstacles that needed to be overcome, the City of Surrey began to plan out a program that would facilitate the mandatory replacement of private sewer laterals in desperate need of improvement.

Identifying Actions

After determining that 30 to 70 percent of inflow and infiltration originated from sewer laterals on private property, the City recognized it was important to identify actions that targeted private property owners. Since Surrey was a relatively young community that had not experienced much damage to homes from sewer backup and basement flooding, the local government was not under immense time pressure to introduce adaptation measures. However, as climate change made this a more pressing issue, the government also recognized the need to be proactive with their adaptation actions instead of addressing issues with sewer overflow after they had occurred and harmed infrastructure or water resources. Taking all these factors into consideration, the City of Surrey determined that the best course of action to reach the private sector would be the introduction of a by-law that outlined reasonable conditions that triggered the mandatory replacement of sewer laterals (sanitary and storm). Jeff Arason, Manager of Utilities for the City of Surrey, mentioned that requiring all homeowners to change their sewer laterals, which would equate to approximately 90,000 sewer laterals in Surrey, would be practically impossible, but using building permits as a way to enforce the by-law would be very efficient. The general view was that private property owners were not aware of the health of their sewer connections, and a period when property owners choose to make a significant investment in renewing their homes would be an ideal time to assess the state of their sewer laterals. This became central to the development of the by-law.


Now that the by-law has been implemented, several triggers can lead to the replacement of sewer laterals in Surrey. If the service connection or building sanitary sewer is more than 30 years old, replacement or new service is required when a property owner applies for a building permit with construction value greater than $100,000 or where a parcel of land is being redeveloped. This trigger, outlined in the by-law, ensures that older sewer laterals more susceptible to damage and failure are replaced when the property owner is already engaged in a significant investment in the renewal of their building. If a building’s sanitary sewer lateral is less than 30 years old, then an application for a building permit for construction value greater than $100,000 or a parcel redevelopment must include a video inspection of the service connection. The City will then review the videos to determine if the connection is adequate or in need of replacement due to excessive damage. This makes the by-law extremely reasonable, and helps the City achieve their goal, which is not to replace all private sewer laterals, but to conduct assessments where possible and only replace connections that threaten the community and are in need of improvement. Another element of the by-law is that all no-corrode, asbestos, cement, or clay service pipes must be replaced, regardless of their age, because their proneness to excessive inflow and infiltration poses a threat to the community. Also, any shared service connections and building sanitary sewers have to be replaced when an application for a service connection accompanies a building permit for construction with a value greater than $100,000. More details are outlined in the by-law; however, the important components were clearly outlined in an easy-to-understand manner when the by-law was implemented. Reasonable, specific triggers were established for mandatory sewer lateral replacements in the private sector.

Outcomes and Monitoring Progress

Creating the by-law was a relatively simple, proactive adaptation action, and no one has challenged it since its implementation. Since most development in Surrey has occurred over the past 30 years, the City has not experienced many circumstances when private laterals required mandatory replacement. However, the implementation of the mandatory sewer connection replacement program provides a mechanism to address an issue of poor sewer connection on private property that is expected to grow in importance over time, especially as intense rainfall becomes more frequent and severe with climate change. The Manager of Utilities in Surrey mentioned that the strategy of using building permits to enforce the by-law has proven to be very efficient. Not only was it reasonable to wait until significant investment in development to require mandatory assessment of sewer laterals, but it ensured compliance as it became a part of the building permit application process. The by-law has spurred infrastructure improvements in times of investment for private property owners – an outcome that the entire community will be a beneficiary of for years to come. An important lesson learned from the adaptation efforts in Surrey was the importance of considering the circumstance for redevelopment. Jeff Arason offered the following advice for other cities that would like to implement a similar by-law: “It is very easy to demonstrate that pipes are at the end of their service life but I think that in future years there will be more and more pressure on municipalities to replace these connections. However, I believe there needs to be some consideration for those that have unplanned replacements of their homes and that cities should be flexible in that regard.” Unplanned renovations are an important circumstance to consider in similar by-laws mandating private sewer lateral replacements.

Next Steps

The next actions for the City of Surrey include applying lessons learned from this project to revise the mandatory sewer lateral replacement by-law. Surrey seeks to focus on property owners that make the choice to invest in significant renovations. An important next step is to update the by-law to exempt property owners required to conduct major unplanned renovations due to unforeseen circumstances. If property owners are forced into major renovations because of a catastrophic fire or other extreme event, it would be harsh to mandate further investment to replace sewer connections. While it may be ideal to replace all outdated or damaged connections, the government must balance this with the fact that homeowners forced into renovations may be in a time of financial hardship, unable to afford improvements to their sewer connections. Apart from revising the by-law to include this exemption, the next actions for the City are to continue monitoring the success of the program since implementation. Mandatory replacements will be triggered more often as time goes on and existing laterals age. The by-law has proven to be effective at its goal of proactive adaptation with private sewer connections, and its effectiveness will further be tested as these mandatory replacements become more frequent. Other municipalities looking to incentivize improvements in private sewer connections should be encouraged by the success of Surrey’s by-law.