We're trying to go from septic to sewer at our church. The sewer hookup situation dictates that we use a lift station.

Our plan is is to use a pair of submersible pumps in our present 2000gal holding tank. The discharge will have to be pumped vertically upward approx 8', and then will dump into a gravity flow sewer line feeder.

Our pumps will be grinder types.

I'm trying to get a feel for how small (in hp) we can get by with in our pumps. Bigger is more expensive.

With the 8' head, what line pressure should we be seeing at that point? There will be a gooseneck above ground, and I intend to put a gauge on it. I would think a 0-15lb gauge would be sufficient.

I'm hoping we can get by with 1 hp pumps.

I had a similar problem at my church which required a lift station with a grinder pump. My best advice is to not skimp - get the top of the line, biggest grinder pump that the experts advise....Our initial pump failed twice before we got the bigger one. I don't know how many signs you post in the restrooms, someone is going to put items down the toilets that will get stuck at the pump. Our nursery was flooded twice with sewage - we had to have it professional remediated - base boards and sheet rock pulled off the walls so it could be disinfected etc. Good luck !