In NYC it is common for a property owner to become aware of a sinkhole on their property, sidewalk or the roadway in front of building. It is important not to ignore a sinkhole, identify the cause of the hole and the resolution. Many property owners want to ignore a sinkhole because they are afraid of the cause and what it may take to fix it.
The problem with ignoring a sinkhole is that you may have an issue that is going to worsen over time and potentially start to become a health or safety hazard. Another problem with ignoring a sinkhole is that the cause of the sinkhole may have nothing to do with you or your property however, it may be showing up near your house and appear to be your problem. In this case your neighbor or the city may be responsible but if they are never made aware they cannot fix the issue which ultimately may cause damage to your property.
How can a sinkhole become a health or safety hazard?
The biggest concern is that the sinkhole continues to form, weakening the grounds surrounding the initial hole and a person falls inside of the hole. Similar scenarios are reported around the city each year and should not be ignored. You should start by surrounding the area with cones, barricades or caution tape to make sure that nobody is within 20′ of the hole. The grounds should remain this way until the scenario is diagnosed and a formal resolution is concluded upon.
Similar to people, cars may fall inside of a sinkhole that is forming in the roadway. It is common for the cause of a sinkhole to undermine all of the dirt below the roadway asphalt leaving a 4″-8″ layer of asphalt before a gaping hole is exposed. The asphalt alone is not meant to support the weight of cars driving and is more prone to collapsing.
A sinkhole may become a health hazard if your sewer line is causing the hole to form, you may have a broken sewer for years and not even know it. If the sewer is broken the raw sewage from your house will seep out of the break or cracks in the sewer pipe, and start to erode the surrounding earth. If you have a small crack in the pipe the sewage will slowly leak until the crack enlarges and begins forming your sinkhole. This will become a health hazard if your sewer begins backing up creating a sewer smell and possibly even releasing sewer gases in your home.
What is the cause of your sinkhole?
Generally speaking a sinkhole is formed if the initial back-filling of dirt or restoration of the sidewalk/roadway was not completed properly. More common is if a water main or sewer is broken and leaking into the surrounding earth. If your water main is leaking it will continue to leak until the earth is eroded to the point of an undermine below ground and finally the pavement or cement will fail, creating a sinkhole.
When dealing with a water main leak you may even experience a steady stream of water exiting out of the sinkhole until it continues to widen and at this point a large portion surrounding the initial sinkhole may collapse. It is also common for the leak to find another path below ground and no longer appear to be leaking from above ground, in a case like this the property owner is usually relieved thinking that the issue no longer persists.
It is important to understand how a water leak will travel and continue to flow until it finds its weakest point in the earth and follow the path. For example, you may experience the water leaking showing up directly out of the sinkhole and a day later it is showing up 15′ away in front of a neighboring property. During the life of your leak the grounds gave way allowing for another path below ground and the water will follow as this path allows. It is important no to ignore a leak if the path has traveled as it is common for it to show up again but in a much more severe case, which may cause damage or an all out loss of water to your property. If you are experiencing a similar issue it is important to call your licensed plumber for a professional opinion.
When dealing with a broken sewer you may not experience any form of water from above ground and may only find a sinkhole for an extended period of time. It is always suggested to obtain a camera inspection of your sewer line and confirm that the sewer is broken in a location close to the sinkhole.
Once confirmed you should complete an emergency sewer repair to avoid any additional issues, danger or a complete failure of your sewer system. If you have any questions specific to a sinkhole near your property it is strongly suggested to call a licensed professional for a on site review, in most cases there should be no charge for the review and no downside for the property owner to obtain feedback.