InspectAPedia®   -   Search InspectApedia

Sinkhole or drywell collapse in New York (C) Daniel FriedmanSinkholes & Sudden Ground Subsidence
Sinkhole Diagnosis & Action Guide

  • POST a QUESTION or COMMENT about sinkholes what to do if you suspect or know that a sinkhole is developing or is active at your property or building

Sinkholes:

Immediate safety actions to take if you discover a sinkhole.

This document suggests some safety-steps if you observe a sudden yard collapse - a potential or actual ground subsidence, and discusses safety concerns as well as what sinkholes are and why they occur, describes their effects on buildings, and gives building and site inspection advice useful in identifying areas where there is an increased risk of sink holes at properties.

The bare minimum that a property owner needs to know about sinkholes or any other sudden subsidence of soils at a property is that these conditions might be very dangerous.

Someone falling into a sink hole or into a collapsing septic tank could be seriously injured or even die.

InspectAPedia tolerates no conflicts of interest. We have no relationship with advertisers, products, or services discussed at this website.

- Daniel Friedman, Publisher/Editor/Author - See WHO ARE WE?

What to do if a Sinkhole or Soil Subsidence is Observed or Suspected at a property

Photograph of a sink hole swallowing a house in Florida

If a suspicious hole, subsidence, or depression appears at a property the owner should rope off and prevent access to the area to prevent anyone from falling into the opening, and then should seek prompt assistance from a qualified expert, geotechnical engineer, septic contractor, excavator, or the like.

Quoting from our sink holes article

If a sinkhole is already visible near an inspected property or if signs of a sinkhole are observed the observer and/or property owner should contact local authorities (building department, police, fire department, depending on the size, location, and apparent seriousness, and the area should be roped off for safety.

If a sinkhole is noticed during a building inspection this information should be cited by the inspector as a potential safety concern and significant expense requiring immediate professional action. Synonyms and similar terms for sink holes include: shake hole, swallow hole, swallet, doline, cenote, moulin, and glacier mill.

Watch Out: Sinkholes or even small soil subsidences can be an immediate potential life-safety concern. For home owners, inspectors, professional and trade association standards, building inspection & home inspection standards, and in some states, inspector licensing regulations (should) require you make to appropriate notifications.

Article Contents

How to Research an Apparent Sinkhole in Your Neighborhood

Classic sinkholes have their origin in earth formations, possibly aggravated by very large scale human-directed operations such as coal mining, oil, gas, or water removal from the earth, etc. Those sinkholes have large-scale underlying conditions.

Local, individualized "sinkholes" may be caused for example by soil wash-out from a burst water main below a city street. Or a sudden collapse of a buried cesspool, or soil subsidence over locally-buried brush and trees.

Local individualized sinkholes may still be dangerous, but once their cause is understood, affected property owners can more reliably and more easily estimate the chances of that sinkhole's spreading, increasing, or suddenly reappearing under a nearby building.

What to do About a Sudden Subsidence or Yard Collapse

Watch out:  Immediately rope off the area of any soil subsidence or suspected old septic tank or cesspool area, and mark it plainly as unsafe so that a wandering neighbor, adult or child, does not go near nor fall into this hole. It could be quite dangerous. See CESSPOOL SAFETY WARNINGS for examples of potentially fatal cesspool collapse hazards.

We are elated that no one fell in to the hole, and that no one walked-over and fell into what may have been an imminent collapse well before it was so visible - such catastrophes can be fatal.

Better Off if it is Not a Sinkhole

If the back yard cave-in is nowhere near any buildings, and if you can establish that it is not a true sink-hole but rather something local like an old cesspool collapse, it probably is not a risk to the building foundation. At events such as this one it is proper to ask if the cause was an old septic tank, drywell, or cesspool, long abandoned and not filled in.

Local Flooding and Sinkholes

However the area where this back yard sinkhole was observed has been reported to produce (smaller) soil subsidences and "sinkholes" due to the combination of clay soils, poor drainage, and a history of local flooding in times of heavy rain.

For example see Sinkholes in Whitestone New York Associated with Flooding Conditions.

Signs of Old Septic or Drywell Components

Look at and in the hole itself and at any debris to see if you see pieces of piping (upper right near the drywell in the photo) - identifying these can save you some future worry and maybe geotechnical engineering costs - that is, if we can be sure it was an old tank and not a sinkhole the risk of other sudden collapses and sinkholes is of course less. In this case the piping visible in the photo was identified by the owner as electrical, from an electrical lighting pole that fell into the opening, not septic components.

The light colored material in the hole in our photo above was considered to be due to clay soils, not sewage waste.

Finally, if it was an old septic tank, or cesspool, warn neighbors whose homes are of similar age that they might have the same condition and the same hazards lurking.

What if it Is a Real Sink Hole?

IF there remains a concern that this is a true sinkhole the risk of other property subsidence that could also threaten buildings could be important.

Your local county and highway or building departments can tell you if sink-holes have been found in your area - you may need the services a local geotechnical engineer to inspect the site, possibly taking soil borings, and then advise you further. Other clues about imminent sink-holes and sink-hole collapses are discussed

at SINKHOLES, WARNING SIGNS.

Sinkhole Repair Services

Companies identify themselves as sinkhole damage repair experts are listed at SINKHOLE DAMAGE REPAIRS or select a topic from the closely-related articles below, or see the complete ARTICLE INDEX.

Sinkholes and Sudden Land Subsidence References, Products, Consultants

...


ADVERTISEMENT



Reader Comments, Questions & Answers About The Article Above

Below you will find questions and answers previously posted on this page at its page bottom reader comment box.

Reader Q&A - also see RECOMMENDED ARTICLES & FAQs

On 2018-07-24 - by (mod) -

Not that I've encountered. I think your neighbors and your local health, police, and safety officials figure it's enough of a reward to the person calling-in a sinkhole for the person to realize they may have saved their own life or that of a neighbour.

On 2018-07-24 by Erik

If you call in a sinkhole in your neighborhood can you get paid for calling it in?

On 2018-04-13 - by (mod) -

Jane

If you think there's a life safety hazard where you live, and if your building management have been informed but you feel that unsafe conditions remain you may have to take recourse with your local building department.

On 2018-04-13 by Jane Doe

Its a hole in the parking lot of the building I live in, the maintenance man patched it, within a week it back,I think my landlord is too cheap to repair it,but its getting bigger and bigger.I didn't use my real name, because I don't want to get put out

On 2017-05-19 - by (mod) -

Alfred,

You need to call someone local who can make an onsite inspection and assessment. If you fear that there is an immediate threat to life-safety, get everyone away from the area and call emergency services.

On 2017-05-19 by alfred castro

I might have a problem with a Sink Hole ocuring in my backyard need immediate attention to this problem cell 808 7410315

Question:

(Mar 26, 2014) Marg said:
If the city made everyone go to city sewer system, who was responsible for filling in the old septic system?

Reply:

Marg this is a septic system local ordinance question not a sinkhole question. Unfortunately I doubt there is a single "right" answer about who bears what responsibility and cost, but I'd expect that the property owner will be responsible for proper and safe abandonment of their existing septic tank. Ask your local building department and let us know what you're told.

Question:

(June 28, 2014) monica said:
Are there any sinkholes in Contra Costa county?

Reply:

Monica,

Sinkholes have been reported in

Contra Costa county in Florida
Contra Costa county in California

In Florida sinkholes occur in many areas of the state but are most common in Hernando, Hillsborough and Pasco counties. Sinkholes in South Florida are less common.

Question:

(Dec 11, 2014) LISA said:
My bathroom door is very hard to close all of a sudden. My bedroom door closes if I open it, and if I open my refrigerator door a little, it swings wide open. There was a bad leak under my apartment complex that went without being repaired for several months. I am worried a sinkhole is developing.

Reply:

Lisa

Check with your neighbours: if the building is settling there may be others with the same concerns that you describe, confirming the theory about movement. Ask your building management to check for building movement signs such as the presence of a sinkhole, foundation damage, cracking, bending, bowing, buckling - an onsite expert is needed : this is not a concern that can be diagnosed by e-text.


...

Continue reading at SINKHOLES COURSE - X-Ray Vision? - can careful attention to site details help spot hard-to-see clues indicating a sinkhole or other dangers?, or select a topic from the closely-related articles below, or see the complete ARTICLE INDEX.

Or see these

Sinkhole & Subsidence Articles

Suggested citation for this web page

SINKHOLES - IMMEDIATE SAFETY ACTIONS at InspectApedia.com - online encyclopedia of building & environmental inspection, testing, diagnosis, repair, & problem prevention advice.


Or see this

INDEX to RELATED ARTICLES: ARTICLE INDEX to SINKHOLES

Or use the SEARCH BOX found below to Ask a Question or Search InspectApedia

Ask a Question or Search InspectApedia

Try the search box just below, or if you prefer, post a question or comment in the Comments box below and we will respond promptly.

Search the InspectApedia website

Note: appearance of your Comment below may be delayed: if your comment contains an image, photograph, web link, or text that looks to the software as if it might be a web link, your posting will appear after it has been approved by a moderator. Apologies for the delay.

Only one image can be added per comment but you can post as many comments, and therefore images, as you like.
You will not receive a notification when a response to your question has been posted.
Please bookmark this page to make it easy for you to check back for our response.
Our Comment Box is provided by Countable Web Productions countable.ca

Comment Form is loading comments...

Citations & References

In addition to any citations in the article above, a full list is available on request.


ADVERTISEMENT