Constructing Pump Stations now for Future Use

[jartgo]

I am designing a wastewater conveyance system with a future service area. The proposed system consists of several miles of force main and three pump stations, with zero flow today. Design ADF is about 300,000 GPD, with the largest pump station in the range of 500 GPM. Obviously the system owner has little control over which specific parcels will be developed or when. There is no option which would allow the owner to construct the infrastructure only when demand is present, that discussion has been exhausted and I've been asked to design the system for half of the anticipated build out flow (where the 300,000 GPD came from).

From that standpoint the math is fairly easy. What I'm hoping to get from this post are ideas that I may consider in the design which will allow the owner optimum flexibility with respect to operation throughout the build out of the system. That is, I will include a pad for odor control at some of the stations, but not the odor control system. I will consider control float elevations and arrangements to maximize the flexibility of adjusting the cycle times of the pumps, the largest station will be a triplex station, etc. What other ideas do you suggest I consider in the design?
Thanks in advance.

 

[bimr]

Consider the use of parallel forcemains.

 

[jartgo]

Thanks bimr, that's essentially what we've done. They understand that if the design flows are realized, a separate force main will be necessary. At this time we are only doing a force main considering half of the design flow. I'm more interested in things that I might consider with respect to the pump stations themselves at this point.

 

[jgailla]

The first thing that comes to mind is making sure the wetwells are large enough to accommodate future larger pumps and adequate future storage volume.

 

[nackra]

Did you consider installing pump(s) for current flow (300,000-gpd) and allow for replacement of pump(s) for ultimate flow (500,000-gpd).
Size electrical for ultimate.