Wow, dredged this one up from the archives!!
OK, I'll try to clear up a few things. But know, I have not been directly associated with the system since, like, late 2010. That's 13 years.
1) Test with Shearon Harris? No, certainly not when I was asociated with the outside contractor doing the maintenance; Rumors, I would say, would be false.
2) No contact with who tests them now. Not for 13 years. I don't even know who has the contract, of if City of Raleigh now handles it internally. When I was handling it with the contractor, the whole siren system had to be tested once per quarter, and it usually took a couple days with 2 techs and a bucket truck to do them all. No particular schedule.
3) Sirens are supposed to go off if the level at the dams gets to (I think, and that's a big think) within one foot of the top of the spillway. Or, at least that's what I was told at the time.
FWIW, dams are Lake Johnson, Lake Wheeler, and Lake Benson.
Here's a link to a map of them all, from way back then:
https://www.google.com/maps/d/u/0/edit? ... sp=sharing