I know there are folks here more retentive than myself, and I respect the care exercised in thinking through problems. My inclination is that the complete shutoff routine instituted by the gas utility after this low pressure event was overkill when trying to return service in the middle of the winter.
Pilot safeties have been around since the 1920s if not before. Most automated electronic equipment would have locked out anyway. So the main danger is someone trying to figure out what was going on turned on a stove burner and then didn't turn it off and doesn't pay attention for some hours after restoration. Given the recent memory of the Merrimack Valley apocalypse I get that the normative protocol when service has been interrupted is to a cursory check by gas company before turning it on but when service is off to 7000 people and its single digits I wonder about how absolute that protocol should be.
Even if one were to believe that temperatures were moderating and its too late to protect against any damage that actually occurred during the first cold night, the incident was grossly prolonged by the dogged insistence on shutting off every service. To me this was going too far even if simply turning the gas back on the first night would have been rash. Being a community with summer homes many people were not home and locksmiths had to be engaged to get into vacant homes. If the home is vacant, then nobody was going to turn on the gas burner and leave.
Whereas in the Lawrence incident the gross overpressurization brought the piping itself into question that was not at all the case here. And if efforts to block additional and redundant delivery capacity for natural gas continue , this unprecedented incident could be repeated. (enbridge isn't speaking in terms that can really be accurately parsed yet. there definitely was an equipment failure but they are presently indicating that that was contributory not exclusively causative and that the extreme low temperatures and high use were the background cause. cutting against that explanation is that gas generators had not been asked to swith fuels, although reading between the lines, it seems that they were running right up to capacity so that what would have been a nuisance equipment failure had a magnified effect - and the fact that it only showed up at the very end of the spur seems to corroborate that.)
So it might be time to think on these questions. I don't mean to be cavalier but I do wonder about the actual risk vs. the actual harm caused by extending this outage to a full week over an hour of outage. I also think we might do well to have controls on hydronic systems that continue to circulate in response to cold temperatures and lack of boiler response. many do but some don't. perhaps an electric auxilary incapable of heating the house but provide enough btus to prevent the tubing freezing is an alternative to the obvious anti-freeze 'solution' which has it's own complications.
thanks for your thoughts.
brian
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