When buying a home with an older sewer line, the risk of line damage increases in proportion to its age.
This is why inspecting the sewer line is important for older homes and / or when advised by a licensed home inspector, noting this is usually a specialized service over and above what most, but not all, home inspectors will usually offer homebuyers as part of their scope.
Kelly Grant's top ten risks typically affecting the overall health of a sewer line include:
(1). The age of the line [note: sewer lines can often be due for replacement every + / - 50 years (varies)];
(2). The grade of construction materials (and surrounding ground compacting) originally used for the line;
(3). The quantity and intensity of soil pressures engaged around the circumference and length of the line (including possible tremors or earthquakes in those areas which experience these geological events);
(4). The quantity and size of trees (and roots) within ‘root growth’ proximity of the line (note that root growth penetration, if not kept in check, can also cause structural damage to a home’s foundation);
(5). The history of the volume of occupants (i.e. including owners' family members, renters, and visitors) using the line;
(6). The history of any abuse with line blockage (e.g. flushing foreign or dangerous materials);
(7). The history of scoping and augering that have detected and / or removed previous penetrating roots or blockage or breaches in the sewer line and of which may indicate a possible collapse in the future;
(8). The history of any past sanitary storm sewer backups and flooding in the neighborhood;
(9). The possible installation (or lack thereof) of a back flow preventer valve (note: installing a back flow preventer valve, depending on the insurance provider, can reduce the premium of one’s home insurance and in fact some insurance companies require that a backflow preventer valve is or will be installed); and
(10). Mushiness or linear settlement of the ground (or rotten sewer smells detected) above the location where the sewer line leads from the house to the manhole / sanitary storm sewer which can be indicative of a very serious problem – a possible sewer line collapse requiring extensive earthwork, etc. to remedy.
Note that items (5) through (8) above are very often guesswork, and not possible to ascertain anywhere close to 100% certainty particularly for those homes with multiple owners or renters spanning several decades.
For any sewer line, the part of the line from the house to the City / Municipality land is usually owned by and is the responsibility of the homeowner while the remaining connection portion of the sewer line to the storm sewer (i.e. the portion of the line on City property) is owned by the City or Municipality. For this reason (and others) it is advisable for homeowners to notify the City or Municipality in advance to share the total cost of repair. Usually the City or Municipality will pay for and replace their portion of the line at the same time as the property owner completes his / her portion to (a). Help minimize cost; (b). Minimize disruption to the homeowner (i.e. as opposed to opening up the land on two different occasions); and (c). Ensure that all portions are new so that there are not ‘old portions of the line’ still causing problems. Sewer line replacement costs can vary widely based on a variety of factors but with today’s construction costs a range of $8000 to $15,000 + (excluding the City’s portion) is not unusual for many homeowners. For an estimate homebuyers must contact a professional earthwork / utility line company.
Note that the effective age of the home does not always guarantee the age of the sewer line. Some homes in the past may have been built on an old foundation and sewer line. Getting the home well inspected (with a sewer line inspection conducted if suggested by the home inspector) is advisable to determine any issues that may exist. The City of Edmonton (as an example) along with other municipalities in the past several years have upgraded requirements to ensure new homes built must also have new sewer lines. Note that duplexes may or may not have separate sewer lines per side (e.g. a condominiumized duplex may have only one service connection for the entire property).
In summary, below are some proactive steps that homebuyers can take to check a property’s sewer line:
(a). Hire a licensed home inspector to check the house and ask if sewer line inspections are part of their scope. If not, listen carefully to see if there is any evidence of sewer damage detected and particularly if the home inspector recommends a sewer line inspection of the house for its age and other factors.
(b). Hire a professional scoping company (many professional plumbers will also provide this service) who uses video to scope through the line to check for any blockage or damage; at what length on the line the blockage occurs; and what is causing the blockage.
(c). If any blockage is detected in the line hire a professional augering company to clean out the line.
(d). If tree roots are the cause of the blockage, hire a professional horticulturist to remove / haul away.
(e). Based on professional advice received, if any lines are significantly damaged; collapsed; or in danger of collapse, after contacting the City or municipality proceed to hire a professional earthwork / utility line company to replace the sewer line.
Final note: paying to install a new sewer line is not a waste of money and can be a very good investment since upon selling a home, it could be advertised by your REALTOR® as a positive house feature which helps to set your home apart vs. other similar-aged homes in the neighborhood that have not had this work done.
[Article written and ©2014, ©2020 by Kelly Grant, M.Eng., ABR, NCSO, P.Eng. - REALTOR® at MaxWell POLARIS in Edmonton, AB]
Disclaimer: for those readers not currently represented by another licensed REALTOR®, to obtain more information on this topic and / or if will be selling or buying in the Greater Edmonton Area, call Kelly at 780-414-6100 (pager); text Kelly at 780-717-9290; or send Kelly an email to SOLD@KellyGrant.ca to schedule a confidential appointment.