Photograph of  a seepage pit collapse at a residential propertyCesspool Safety
Inspecting, Testing, & Maintaining Residential Septic Systems - Cesspool Collapse Hazards

  • CESSPOOL SAFETY WARNINGS - CONTENTS: Cesspool Collapse Warnings and Cesspool Safety . Warnings about cesspool collapse and fatality hazards. Cesspool rejuvenation, agitating, jetting, or hydrojetting cesspools vs when to install a new cesspool or drywell
  • POST a QUESTION or READ FAQs about safety hazards, collapses, explosions, fires, toxics, injuries and fatalities involving septic tanks, cesspools, drywells, and other septic system components

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Septic & Cesspool or Drywell Safety Hazard Warnings:

This document explains and describes some critical safety concerns for people owning and maintaining cesspools for onsite waste treatment. Cesspools, depending on how they have been constructed and how they are serviced, can present particularly dangerous conditions and risk collapse and fatal injury. The hazards described here in discussing cesspools can also be present at drywells and seepage pits.

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Cesspool Safety Warnings and Cesspool Capacity Limitations

Sinkhole or drywell collapse in New York (C) Daniel FriedmanQuoting from our sink holes article:

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. 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.

This document is a subchapter of our online text about cesspool design, cesspool installation, cesspool maintenance and cesspool inspection. These pages explain what a cesspool is, gives important safety and maintenance advice for cesspool systems, and defines the criteria for cesspool failure.

We also provide critical safety warnings concerning cesspool systems as with some older and especially site-built cesspools there is a risk of dangerous collapse or cave-ins.

This material is a chapter of our Septic Systems Online Book: That document explains septic system inspection procedures, defects in onsite waste disposal systems, septic tank problems, septic drainfield problems, checklists of system components and things to ask. Septic system maintenance and pumping schedules. Citation of this article by reference to this website and brief quotation for the sole purpose of review are permitted. Use of this information in books or pamphlets for sale is reserved to the author.

Some technical review by industry experts has been completed-reviewers are listed at "References." Review comments and content suggestions are invited. Home buyers should see the Home Buyer's Guide to Septic Systems.

Also see SEPTIC & CESSPOOL SAFETY - Septic System, Septic Tank, & Cesspool Safety Warnings for Septic Inspectors, Septic Pumpers, and Homeowners.

Very Important Cesspool Safety Warnings

Sinkhole or drywell collapse in New York (C) Daniel Friedman PHOTO of a septic seepage pit collapse when a truck drove over it.

In Summary:

Watch out for cave-ins, keep away: cesspools, particularly older site-built cesspools present a very high risk of collapse from an unsafe cover or following some types of service involving pumping, aeration, or hydro-jetting.

Adults or children should not walk over or even near cesspools because of the risk of falling-in followed by collapse, a virtually certain cause of death.

If the presence of a cesspool is known or suspected at a property its location should be roped off to prevent access and it should be investigated by a professional.

When to Install a New Cesspool or Drywell

Question: When is the best time to install a new cesspool?

I need a lot of information because I am going to buy a new cesspool. When is the best time to buy one? I was told winter is the best time to buy a new cesspool? But the ground is frozen now. What temp is right? What is the average price? House was built 1950 (maybe). Does new cesspool come with new cover? Can I have my clothes line on top of old cesspool? How do I get rid of odor in my basement? When they put the new cesspool in do they check pipelines in and out of house? If so how? Do I need to get new pipes in side? Does a plumper know best, when to replace pipes? - S.H.

Reply: Wet warm weather

The season in which a cesspool is to be installed affects the cost and may affect the outcome too:

So it's probably cheaper and smarter to dig during the un-frozen wet season.

Of course, if your building relies on a cesspool or drywell to function and the present system has failed, you may be forced to install the new cesspool or drywell without waiting.

Cesspool cover:

Cesspools, if you buy a pre-fab pre-cast unit, are made of concrete. You may have a choice of cover - a heavier duty one that can be driven-over without collapsing is smart. But a safe cover must be included in your bid price regardless.

Watch out: falling into a cesspool or drywell is likely to be fatal.


Putting a Clothes Line over a Cesspool:

A clothes line won't hurt the cesspool if you don't drive a post into the cesspool top.

Getting rid of Old Sewage Backup Odors:

Odors go away by cleaning and sanitizing the area of any sewage backup and airing it out. If odors remain you may have an outdoor failure and outdoor sewage odors as a source, or you might have an indoor plumbing vent problem.


Building Codes, Permits, Approvals for Cesspools and Drywells

You need an experienced plumber and cesspool. installer to help locate the new cesspool, connect existing building drains to it, and to assure that the building drain/waste/vent piping are working properly.

Don't forget to obtain a building department or health department permit and approval, and to install it correctly and safely.

Watch out: Some municipalities do not allow cesspools - so check with your building department.


Continue reading at CESSPOOL FAILURE CRITERIA or select a topic from closely-related articles below, or see our complete INDEX to RELATED ARTICLES below.



Or see these

Key Drywell & Cesspool Articles

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