Overboard discharge from marine head ...

[Gunni]

So, a Type I MSD, such as Lectra San, which reduces bacteria and BOD to an acceptable level does not reduce the nutrient pollution and this is the reason they are not accepted in a zero-discharge zone?

I agree that nutrients are a significant problem. Nobody enjoys blue-green algae or other forms of algae bloom. Excessive weed growth has plagued my prop this summer around my slip as the water level has dropped. Non-point source pollution is regulated to a meager extent when it comes to agricultural run-off. Basically, the State is far more concerned about controlling erosion from building sites than it is about the far greater non-point source pollution from agriculture. Sacred cows exist.

Yes, the Lectra San does not reduce nutrients like nitrogen and phosphorus in the waste discharge. The CWA gave vast regulatory exclusions to the mining and agriculture industries regarding their discharges. And their political lobby continue to fight any discharge controls. However, just last year a Federal judge ruled that the EPA has the authority to issue pollution limits where states fail to do so. And EPA can establish total maximum loads for a given body of water - crossing state and local boundaries. So runoff isn't safe any longer.

 

[Gunni]

Not sure what to say

Well what you don't want to say is "I am no longer concerned about any untreated sewage discharge less the 1,369,863 gallons per day." Because periodic stormwater overflow discharges never contain 1,369,863 gallons of untreated sanitary sewage per day. These stormwater / sanitary sewage combined flows occur an estimated 75 days per year during high rain flow events and contain only a small unresolved fraction of sanitary sewage. At all other times the city treatment system captures and treats all sewage to a very high discharge quality.

I might add that Alexandria, like most older cities have the same system, and the same periodic combined sewage discharge.