M.A.R.I.N.

Nigel and myself, accompanied by cap Lars took a 2 night trip to Bangor. We wanted to make a data trace from river Lagan using the YSI 600XL Sonde, recording temperature, pH, salinity, dissolved oxygen and oxygen reduction potential. It was another summer in Belfast with lot of rainfall, so there should be a lot of nutrients in the water. Weather forecast was luckily wrong for the day we went out: it was sunny with a smooth South-Westerly wind that made it a pleasant sail after the harbor area motoring zone. We also stopped along the way to make hydrophone recordings.

Once in Bangor, we sought permission to take the catamaran onto a slipway. One of its folding propellers had corroded and literally disintegrated. Also it was time to get rid of some barnacles. They are an amazing species, leaving a substrate behind even when removed, leaving a “bed” for new larvae. Think we removed about 60kg of it from the boat, and put into trash. The catamaran looked mighty big when off water, yet also beautifully designed.

Before dusk, Nigel and I took out the little dinghy boat with the water testing kit and hydrophones. At the entrance to the harbour, a dozen of fishermen were casting for mackerell. A few seals also loved this spot, not least to the treats that returning fishing boats would give them, the unused bait. We got pretty close, 2 meter distance from one of the seals, which seemed to have lost one eye. We tested the water in the commercial and yacht harbor, and then went out to Luke’s point, an area where I knew Bangor still has open sewage to the sea.

An unfriendly, cunning rock crept up from the sea to scratch the small engine propeller on the way. When going out to the sea, dissolved oxygen levels improved significantly, but when approaching the spill area, we’d hit values closer to six mg/l DO. The readings were showing worse water quality 200 meters off shore at the spill area than in the visibly polluted commercial harbor of Bangor.

The calculation one city may do is whether the wider impact of their sewage output has long term effects on wider aquatic areas. As it washes out to the open sea, the impact is in the short term, regional. What about the longer term stress on the marine ecosystem?

In the harbor, rather new mussle boat with trawling gear was in the harbor. On the coastal road, there was a sign warning to eat any mussels in Belfast Lough because of pollution. I turns out that the mussels in Belfast lough are replanted in other waters, grown, cleaned and sold.

We slept two nights in Bangor, and sailed off early in the morning to record a track from Bangor to the other side of the Lough near a power station, then up to the beginning of the Fairway buoy. The weather was rather windy.

Our water quality testing is something I would call indexical work. In order for the data to be meaningful for science, it takes a long period of time to monitor a single site to take into account changing conditions, and the possible measurement errors (which always are part of the picture). The mobile kind of monitoring that we do helps give an idea of an existing issue that may be worth investigating closer. For example, there are no permanent measuring equipment stationed in front of Bangor to monitor the sewage output.