Jane Disney of the MDI Biological Laboratory gave the Bar Harbor Town Council some good news last week.
“I have nothing to report but clean water this year,” she said while presenting the results of water quality monitoring in the harbor during 2015.
For several years, the town has used some of the income from cruise ship passenger fees to keep an eye on harbor water quality. Among the factors being monitored are bacteria, turbidity, salinity, dissolved oxygen, nutrient loading, chlorine and phytoplankton.
Those tests consistently have shown that visiting cruise ships are not degrading local surrounding water quality.
With as many as 140 ship visits each year, some by vessels that carry up to 3,000 passengers and almost as many crew members, the potential for negative impacts on water quality is a serious concern. It would not take long for even minor discharges from such ships to pose a serious environmental problem and potential health hazard.
In fact, the only incidents of note involving improper discharge of gray water or bilge liquid have been comparatively minor, and have originated from the smaller ships that tie up at the head of the town pier, not from the leviathans in the outer harbor.
A handful of above-average bacterial readings on samples taken near the town beach from time to time may, in fact, result from other sources, including pet waste from unmonitored dogs.
Fortunately, the cruise lines that make port calls in Bar Harbor have been good environmental stewards. Their customers want to visit clean natural areas and would abandon them in droves if they thought the ships were despoiling top destinations.
In wrapping up her report, Disney explained that while the results are encouraging, it is important to keep testing.
“I don’t think you should rest on your laurels after you’ve come this far,” she said.
She’s right. Bar Harbor’s reputation for natural beauty and a clean environment is the community’s greatest asset. The best way to assure it remains that way is continued vigilance.