InspectAPedia®   -   Search InspectApedia

Photo of a community sewage pumping station Inspection & Maintenance Guide for Septic Sewage Pumping Stations

What is a septic pumping station or lift station?

Here we illustrate a septic pumping station for a small community wastewater handling facility.

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

What are Community & Housing Development Septic Pumping Stations?

Sketch of a municipal pumping station

Our sketch (left) illustrates a typical sewage pumping station schematic, including the pumping cvhamber, inlet and outlet piping, an elevated grinder pump and floating pump switch, and a pump control box accessible fdrom the manhole cover.

This article is a section of our online book SEPTIC INSPECTION & TEST GUIDE whose chapters are shown at the end of this article.

Septic pumps used for pumping air in aeration systems and septic pumps used to move effluent in a drip dispersion system are discussed under the appropriate septic system type which are outlined at SEPTIC SYSTEM DESIGN ALTERNATIVES.

Photo of a community sewage pumping station

A community sewage pumping station uses a large centralized chamber to receive wastewater from multiple buildings at a single site or development and then grind and pump the wastewater onwards towards a wastewater treatment facility.

The photo at the top of this page shows a large sewage pumping station serving a shopping complex in southern New Jersey.

The photos at left and below show a sewage pumping station serving a residential community in Pawling New York.

Vertically suspended submersible sewage ejector pumps use a motor secured to the sewage reservoir cover. The pump is basically held in place by the connection of the pump motor shaft to the pump housing which is inside the reservoir.

Closely-coupled submersible sewage ejector pumps use a motor which is secured not to the sewage reservoir but rather directly to the pump mechanism itself - to the housing for the pump impeller which actually grinds and moves the wastewater.

A short shaft connects the closely-coupled sewage pump to the impeller housing and impeller, and the entire assembly is submerged in the sewage reservoir.

Sewage pumping stations are needed where all or some of the homes or buildings in a community are located downhill from the greater community's sewage mains.

Wastewater drains by gravity (or if necessary by individual building septic pumps) from individual buildings in the community to the local septic pumping station which has a holding tank big enough to act as a receiver for wastewater from the community.

From the receiving station, wastewater passes through one or more sewage grinder pumps through a pressurized sewage force main (pipe) which transports the waste uphill to a location from which the wastewater can drain by gravity through additional piping to the community's wastewater treatment facility.

The septic pumping station will typically use two or more sewage grinder pumps to move wastewater uphill to the larger community's sewage mains where it passes to the sewage treatment plant.

Multiplexing pumps helps assure that the community's waste will be handled even if one pump fails, and also permits staging of pump operations to bring more pumps online if the inflow rate increases.

Photo of a community sewage pumping station

Special Concerns for Municipal Lift Stations & Community Septic Systems

Photo of a community sewage pumping station

We have some special concerns for community sewage pumping stations or "septic pumping stations" or "force mains" as they may be called in some areas.

One unpleasant effect was that homes nearest to the pumping station's receiving chamber suddenly had everyone's sewage backing up into their homes. In addition to omission of a backup generator for the system, the plumbing contractor had not installed check valves in the sewage lines at each home.

Diagnosing sewage backups and how to diagnose clogged drains is discussed

at DIAGNOSE CLOGGED DRAINS & SEPTIC SYSTEM BACKUPS - Is it a blocked drain or the septic system? - A First Step for Homeowners.

The contaminants in sewage that may be left behind when sewage backs up in a building are discussed further at SEPTIC SYSTEM CONTAMINANTS: identifying water and soil contaminants produced by onsite waste disposal systems.

Sewage Pump Force Mains Specifications & Capacities

 




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 2020-10-15 by (mod) - hum and vibration caused by sewer lift station?

RE-posting from private email:

What type of inspector do I need to hire to tell me if the hum and vibration in my home is a result of the sewer lift station in our community? It is owned and operated by our developer not the city.

I have a sewer grate in front of my house and in the past year the noise, vibration and sometimes sewer smell also has increased. The community has expanded in size in the last 2 years so more homes and plumbing pipes have been added.

Thanks for your guidance. BB


Moderator reply:

I don't think that a typical building inspector is likely to be expert in municipal sewage pumping stations and may also not be expert in noise transmission and control.

So I'd start with a plumber who's experienced with the sewer lift station design, installation practices, and maintenance issues in your area, or possibly a sanitary engineer.

It should also be possible to collect noise measurements at the lift station and at piping connected to your home to evaluate the chances that the noise you describe is from that source.

IF the noise is atypical for sewage lift pumps it could be presaging an upcoming pump failure, something that your municipal sewer maintenance people may find useful to know about.

On 2018-09-08 by (mod) - minimum fall septic

Robert,

I'm not sure what you have in mind by "minimum fall" - perhaps a pipe drain slope of 1/8" per foot of horizontal run? That's not the usual limitation.

Sewage pumps will generally be rated in GPM capacity and in LIFT capacity - how high the pump can lift the wastewater or sewage. The assumption is that from the point of discharge the waste flows by gravity to a destination (sewer line or septic tank) so the horizontal distance isn't given.

Example: A Zoeller 1/2 HP Simplex sewage ejector pump has a head or lift capacity of 21 ft. maximum, noting that the GPM rate of the pump (using clean water as an example to get consistent flow rates) is going to drop off as the lift increases.

At 0-5 ft. head the pump can push 128 gpm, while if the lift height or head is 20 ft. the GPM rate falls off to just 10 gpm.

A different case is a sewage grinder pump used on a "force main" that actually pushes ground sewage over some distance. For that type of pumping system there will be both a lift capacity and a GPM flow rate table that considers vertical distance, horizontal distance, pipe diameter, pipe obstructions or bends or elbows, possibly even pipe material.

More about force mains and sewage pumping stations is above on this page.

On 2018-09-05 by Robert

How far can a sewage pump pump with a minimum fall


On 2018-04-21 by (mod)

Anon

There may be a venting or other operating problem with the sewage pump you describe. Find who is responsible for its operation and ask them to check the system operation. Let us know what you're told.

On 2018-04-21 by Anonymous

Yes I have a sewage pump station near my home and it's smell constantly all the time



...

Continue reading  at SEWAGE EJECTOR / GRINDER PUMPS - topic home, or select a topic from the closely-related articles below, or see the complete ARTICLE INDEX.

Or see these

Recommended Articles

Suggested citation for this web page

SEWAGE PUMPING STATIONS 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 SEPTIC SYSTEMS

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