Recognizing Restricted Visibility

Assessing Visibility When on Land

During daylight it is relatively easy to recognize conditions of restricted visibility. If you are on land, say heading for the marina for a mission or for training, you can look around. Is there mist swirling around? Can you see the buildings along the street as easily as you would on a nice clear day? (Clues like these are so readily apparent that we take for granted that we will recognize the conditions as soon as we see them.) So it is simple to conclude that restricted visibility will be an issue once you are on the boat. 

Even at night, restricted visibility should be obvious, if you are on land. You will be familiar with what your neighbourhood looks like at night. Look down the street, are the streetlights sharp points of light or are there blurry halos around where you expect to see lights? Are the house lights nearby in sharp focus or are they diffuse glows in the dark? Are the house lights and street lights a block away visible or not? Although it is now nighttime, the clues for restricted visibility should still be apparent. 

Thus, when you are on land, there are generally several cues for when you are in  conditions of restricted visibility. 

Assessing Visibility When on the Water

But if you are already on the water at night and areas of restricted visibility are developing, you will have fewer cues. Since it is nighttime, you will already be anticipating that you will not see landmarks that are readily visible in good daylight conditions. So, when you do not see these landmarks, it is tempting to dismiss the situation as the normal nighttime conditions: "I can't see what I expect simply because it is dark".

You may anticipate restricted visibility only when you are looking for something specific, but cannot pick it out — "The red light on P54 is easily seen at a distance of a couple of cables, but I cannot see it!" Now your brain should be considering some alternatives: 

(1) "Maybe we are not where we think we are...  Nope, the chart plotter shows we are just two cables from P54."

(2) "Maybe the light on P54 has failed or the buoy is out of position... Could happen!... Nope. Because as we approach we can see a red glow right where we should see P54." 

(3) "Maybe P54 is in an area of restricted visibility (and so are we)." Ah ha! ... Oh oh!!

To detect restricted visibility, our brains should be going through a thought exercise like that frequently when we are on the water in the dark. At night, we should know what lights we should expect to see:

(1) The lights from the town of Comox when inside Goose Spit and for a good distance down Baynes Sound.

(2) Domestic lights along the Vancouver Island shoreline, especially along the west side of Baynes Sound. You should see at least some lights from built-up areas even in the middle of the night, e.g., Royston, Little River. You should also be able to see some lights from Powell River and Texada Island.  

(3) Red lights on various towers on shore: around HMCS Quadra, the radio and microwave towers at the CCG radio station above Cape Lazo, and others.

(4) Lights on aids to navigation: the BC Ferry crossings, P54, PB, the Dolphin, the red light at the end of Goose Spit, and others.  

Thus, we must know what we should see at night, and take warning when we cannot see what we expect.