Hydraulics from Master Lift Stations to WWTF

[PEorl]

I am looking for references on balancing/designing the hydraulics from master liftstations into a WWTF. These liftstations have not been built and I don't have any information yet on flows (other than about 1 MGD each). I am also looking for recommendations on any software packages for this application. Thanks.

 

[bimr]

I have not seen any software packages like that.

The only way that one would be able to balance the flows is to furnish the lift stations with VFD's. VFD's would eliminate the surges from pump start/stops.

 

[francesca]

SWMM or SewerCAD or SewerGEMS. SewerCAD is easier to learn, SewerGEMS can do scripting to overcome the inadequacies in SewerCAD and SWMM can do it if software cost is an issue, but the learning curve will be steeper.

 

[Watthour]

SewerCAD is fine for the collection system, but it has NO business sizing or designing anything from the last lift station or force main into the WWTP. The plant designer alone should have full control over the influent handling. Work WITH them, not against them.

I've probably designed one or two more plants than most of you, and there is nothing more frustrating trying to educate an engineering consultant (who thinks she knows something) that the design won't work, and why.

Specify the influent requirements to the plant designer, including contingencies and storm events, and allow them to build to accept those conditions. Fully disclose the worst case scenario, or you'll be disappointed (and wet). Then hold their feet to the fire. If the plant doesn't work as designed and specified, come down hard.

FWIW, no designer nor PE worth his salt will stamp a plan that doesn't work to the specification. If you provide incorrect specifications, you'll have real difficulty holding the PE responsible.