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Jerrylco
08-26-2012, 01:15 PM
Hi,
I'm new to the forum, been on for 1/2 hr and already posting my second question. This looks like a greeat forum, lots of info and help.
I'm purchasing a home that is currently on a septic system but one of the conditions on the property is that it need to be connected to the sewer system. It appears I'll need a lift station, and about 450 ft of 4" line to get to the main. What kind of costs can I expect for the lift station, the installation of it, and the lines and installation? I know it's all pretty vague from that description but some rules of thumb will be very helpful. Also, what should I know or ask about as I get bids for the work? I've been doing some online research but get the feeling there's a lot more I should know, any good references I could look at?

Thanks,
Jerry

jadnashua
08-26-2012, 02:17 PM
Too many variables. How high do you have to pump things? How deep must the line be burried? Lots of rock, trees, or ledge to go through, around? Do you have to go from the back of the house to the front to get it to the sewer line? Is the basement finished? Do you have power nearby? How easy will it be to get power to the pump?

Keep in mind that in most places, to decommission a septic system, you can't just cap it off. You must pump the tank and fill it with soil/sand/gravel, so that when it may eventually degrade, it doesn't become a hazard when someone breaks through and falls in.

Jerrylco
08-26-2012, 02:38 PM
Thanks for the reply, definitly lots of variable. I did know the old septic need to have the top broken and filled. The lines right now go from the house and are gravity feed to the septic tank using 4" lines. Thats about 25-30 ft of line from the house flowing down hill. From there it's another 50 ft down hill to the road. Once at the road it'll be about 375 ft going up about 20-30 ft of rise to the manhole top, don't know how deep the sewer actually is. I figure the excavating will change a lot based on area, there are a lot of rocks and boulders in the area. I'm more curious about the cost of lift stations that can push that length / slope, and the plumbing aspects. The excavating is very dependent on the area, in this case the Colorado Rockies.

Thanks again,
Jerry

jadnashua
08-26-2012, 03:08 PM
Does the sewer line run along the roadway? Sounds like it's downhill all the way to the road. If it does run along the road, my guess is that they'd make the connection such that you wouldn't need a pump. A pump is to be avoided if at all possible. This isn't an area I've studied, but I find it kind of strange that you'd have to go that far to an existing manhole to make a connection when most connections are made directly to the line as it passes by your property. that might mean tearing up the road, but that's done all the time. The utility has special fittings to tap into the main line.

You need to verify with the utility where you can connect, then, worry about a pump, if required.

Jerrylco
08-26-2012, 04:08 PM
It is pretty strange that the property needs to go that far to the main, or that it needs to go to the sewer, but thats the way it is. The end of the main is 260 ft from the property line, and the main is uphill. Add another 150 ft to the house connection, it's a pretty long run. In that area you'r required to connect to the main if your property line is within 400 ft of it, all at the owners expense. I'm sure a lift is needed, just need to get some costs and estimates for getting the work done.

Jerry

wallskev
08-27-2012, 03:52 AM
You may want to read the attached guide and using the calculations and chart 9.12 to determine overall dynamic head.
http://septic.umn.edu/prod/groups/cfans/@pub/@cfans/@ostp/documents/asset/cfans_asset_131295.pdf

Also critical will be the gallons per day and out flow volume. Will your municipality and utility require certain specifics on the design ?
I once installed a system at my home in upstate New York using used equipment I got from a plant salvage and the utility people claimed it was over sized and I had to reconfigure the system with a smaller pump.

Then contact someone Septic Tank Parts http://www.septictankparts.com at for recommendations on your final design and if just a Lift pump or a grinder pump will be required.

Good luck.

hj
08-27-2012, 06:53 AM
1. you want a two pump system
2. It must have alternating pump operation
3. It must have an emergency "both pumps operating" high water switch
4. It must have an alarm that sounds when both pumps operate to indicate a potential failure of one of them
5. It must have an audible and/or visual high water alarm which indicates that the pumps are not working or cannot keep up with the incoming flow
6. It should have a main line water valve wired to the high water alarm so you cannot continue to use water if the power fails or the pump cannot pump the water.
7. You only need 4" pipe to the pump pit, which should be at the house. The pump discharge can be as small as 1 1/2" pipe, but usually 2", depending on the pumps used.