Having built many of these systems, I can tell you this is commonplace and is their built in safety element. And while no one wants to accept such, the net impact of that overflow discharge into a body of water like that is minimal if not completely non-existent. Yes, of course, no one wants that as any waste is too much, but this system is far better than years past. Many jurisdictions utilized combined storm / sewer and all are working to separate the systems at great expense. In addition, as populations boom and wastewater production gets bigger (think bigger homes, more water consumption, etc), many jurisdictions are investing in storage capacity to alleviate the need to bypass treatment. DC Water/WASA is in the middle of a large underground project where storage/holding tunnels are being constructed to allow dirty water to back up in a high flow event so it can be treated at a later time while under less demand. Arlington County recently overhauled a very large segment of their existing gravity line (with a large part of it under Arlington Nat'l Cemetery) that utilized very large junction chambers to capture/hold large flow during surge events.
I don't work in Calvert County but the fact that it has changing elevations doesn't necessary negate the use of gravity systems. It all depends on the total highs and lows, flows, etc. #### CAN flow uphill if it comes racing down the hill with enough speed. It's all a matter of pipe size, type, elevation change and anticipated flow.
It should reach SOMD on Thursday, enjoy those white perch.........
