Sewer Pump Selection Help

[DTL504]

Because of the slope of my yard to have gravity flow of sewage not possible since the pipe is coming above ground roughly 4-6 inches after the first 50 ft, I decided to add a sewer pump.
Looking for a complete sewer pump system that I can install "Outside the detached garage" with the capability of pushing sewage 100ft through 4" Sched 40 PVC to main pipe leaving the house. What would you recommend and hopefully I can get one from home Depot or Lowes so that I can get the military discount to reduce cost.

As seen in picture with the pipe coming out the garage toward the side gate with connection to the sewer line exiting the house at 1/8" slope. Looking to just drop the pipe 6 inches below the surface and add the sewer pump on the outside before the 45* bend leaving the garage.

 

[70redbee]

Check Lowes or Home Depot for a sewage injection pump. You will need to bury a crock and put the pump in it, very easy install. They should be able to sell you everything in a kit.

 

[larry4406]

I assume you are trying to connect the detached garage to the sewer and your house is already sewered.

Can you connect the garage to the house vs trying to to make it a home run to the house lateral?

My house has a basement, sewer under the slab. I bored a hole in the foundation wall, ran the detached garage sewer thru the hole, and connected to a waste line in the basement.

These are the gold standard sewer pump in my area:
http://www.eone.com/sewer_systems/intro/index.htm

 

[JoeMopar]

Hard to tell from your pictures exactly what you are doing but with 4" pipe you need 1/4" per foot pitch. You need to run the 4" into some sort of pump chamber large enough to set up a proper pump with a series of float switches to monitor the level the black water and control the pump ( in Ct. it's usually a 750 - 1000 gal. concrete pump chamber) From the grinder pump in the chamber to the sewer connection in the street it's usually a 2" line.

 

[Frank The Plumber]

http://www.zoellerpumps.com/ProductBenefit.aspx?ProductID=87

This is what you should use.

I'm almost certain you will not, the problem you will encounter is going to be the dewatering of the effluent discharge through the 100' section of 4" pipe.

This is why a smaller pump is going to give you problems, it will lack the force to send a strong enough current of mixed sewage( solids and water as a vehicle) the length of the pipe prior to the solids leaving suspension. You would also need a basin large enough to supply this unit with a capacity of product to make a cycle.

After looking at your pictures I don't think what you are trying to do is going to work very well unless it is just water, there is no pitch in any of this installation, that is going to trap sediments and debris. You would have been better off using a smaller diameter 2 or 3 " pipe and created a forced main using an ejector pump and a basin going to the sewer discharge. You would need a basin and an ejector to make this thing you have going on here work, as it is built it should receive no sewage, poop or papers, it will not flow them to the end of the pipe and the solids will block the line so tight that you will not be able to even rod them through. Paper dries out like a piece of wood in the line.

This will cause a solid block of dewatered sewage waste.

If the discharge pipe were pitched and the discharge has a flow towards the drain this solves the problem, if it is pumped against gravity it has to remain in suspension until it can reach a gravity drain or another pump or a field for absorption.

Physics is a *****.

 

[DTL504]

After having the inspector come out for the shower pan today I asked the question and he stated that I would need 2" Pressure pipe running from the sewage basin at the garage to the house. Being that I have to use 2" pressure pipe I will be able to get a good slope bed to assist with sewage flow and maintain the 3" of cover.
Next, I would like to get your opinion on the Zoeller 912-0082 Sewage Package (Job Ready). remember I has to push the sewage 100ft to the main drain leaving the house.
http://www.faucetdepot.com/faucetdepot/ProductDetail.asp?product=28901&cat=302

 

[Frank The Plumber]

No, I don't like the basin size on this unit if it is pushing sewage. Remember the water is the vehicle that the solids are floating in, this basin is small in water capacity and if you do not have enough water to wash and transport the solids to the exit they will stay and dry in the line. You need a basin that will give a long enough duration of water flow to hydrate any prior solids as well as transport any in the current water load. A basin is a fairly cheap item if you can use poly in your area so I would get a large basin.
Keep in mind that you are now considered a forced sewer, this equates to using a pressure rated pipe and pressure rated fittings. In most cases this is schedule 80 PVC and schedule 80 fittings with the pressure hubs. If you spoke to your inspector I hope you were informed. If you do not use a schedule 80 system the line can get blocked and that little pump can make enough pressure to blow the line apart and you will have a shitsplosion.
A $300 plus tax pump and a 50 to 100 dollar poly basin should do it, no check valve per the forced main if I remember right. If you do use one it has to be a glue up unit, the pump could blow the rubber couplings off of it other wise.
I pay $310 plus the tax on that 264 pump. I can get a big basin for another $100. That unit is back ordered. I buy my pumps local in case I have a warranty issue.

 

[DTL504]

What you think about this plan of attack for the Garage 2" Pressure pipe head and Sewer Basin installation tied into the house 4" PVC. The picture is not to scale, just a rough power Point Slide.

 

[pstnbly]

The last thing I would normally do is disagree with Franktheplumber, but scd 40 pressure rated pipe (bell end 2") is rated for 300 psi working pressue.

I build many pressuized septic systems and sewer ejection systems, one thing you should be aware of is the pump discharge line will remain full and needs to be frost protected.

A typical sewage ejector pump of 1/3 to 1/2 hp should suffice ( you can calculate TDH (total dynamic head) faily easily. TDH is friction loss of a given length of pipe plus the lift in feet and compare that to the pump curve of the pump you are looking at (google).

Usually a sewage ejector vs. a sewage grinder is sufficiant for residential installations as an ejector normally will pass a 2" solid. Sewage grinder style pumps will probably scare you with the price. The pump will need a check valve placed at the discharge to prevent pumped material from returning to the basin. Pumps do not like to be spun backwards by return flows (it kills them). And a single float (bang bang) should work for control.I would suggest a high level alarm though.

Disclaimer: Local codes apply