What you need is a "water mover"; drainage pumps are typically very high flow, very low head. There are entire classes of pumps designed exactly for this application.
These have high specific speed impellers and depending on the head will either be of axial or mixed-flow design. Usually if the head is under 15 or so feet, you would use an axial flow, or propeller pump. There are designs to accommodate flows up to several 100K gpm. They are essentially a propeller spinning inside the discharge pipe.
The very expensive types have cast iron bowls with liners and cast impellers and are only made by a handfull of manufacturers: Cascade, Johnston (now Sulzer-Johnston), Floway, Flowserve, and maybe one or two more.
If you are on low budget (as all municipal apps are), there are several companies that make "fabricated" pumps of this style. This simply means that the bowl and impeller are fabricated/welded using carbon steel as stock. These are much cheaper and quicker to deliver (no patterns, no castings, no huge machinery to machine castings, etc.).
The design element of these pumps that is most crucial is the bearing arrangement and how they are sealed from the sand/abrasives that they will see. Everyone does it different and this is what the Corps will want to look at for design approval.
DOn't know if they're still around, but LoLift used to make a very good fabbed prop pump for this service. There are several smaller shops that will build these to suit custom applications.
Just google propeller pumps or axial flow pumps and see what comes up.
I am not aware of hydraulic ram design pumps used for this service.