West Bank Park Mapping Operation - Soliciting Help

[Flightlead]

as far as markers go, I reckon that 1/2 gal milk jugs will do, perhaps with a number painted on in hi viz. paint. no sense in using expensive lift/marker bags. each team of two divers could easily take a half dozen. just fill 'em with water at the beginning of the dive and they are neutrally bouyant. attach a line to what you are marking and to the milk jug, add a shot of air, hey presto.

 

[JCDdiver]

We just mapped divers cove last weekend.

 

[DawgDiver]

Well it's not that I NEED a SMB for this, but i WANT one and this is the perfect excuse 8)

Besides, i really need a SMB for boat diving this year.

 

[ShallowDiverDave]

We just mapped divers cove last weekend.

Do you have an image of the cove map JCDiver? If so, could you post it?

thanks,

David

 

[The Kraken]

I already have saved up about 30 yellow 1 gallon milk jugs for such a project.

the K

 

[ClayJar]

If we send surface markers up from the various sites, it'd be easy enough to get GPS coordinates from them. I can just bring my inflatable canoe, paddle to each, and set waypoints. (It'd be a relaxing way to pass a surface interval. )

Consumer GPS receivers are certainly not Trimbles, but with WAAS and no tree cover in the way, the results should be quite useful (and a lot more direct than bearings, distances, and trig). Once you have the set of waypoints, you just calculate the bearings and distances and then dive to verify.

 

[The Kraken]

The GPS is a great idea, but I imagine the resolution for the distance would not be fine enough for diving purposes.

A laser range finder, if bounced off the yellow jugs at the surface, would give us exact distances +/- a foot or so between the different markers.

Establish one marker as primary and then move to the next marker and take the ranging shots on the other marked buoys.

Shoot an azimuth to two different markers from a land based benchmark and then do a simple resection layout of the positions. Headings and distances between different locations could then be determined with some simple trig calculations.

the K

 

[Flightlead]

Is Divers Cove the same as Mask Cove? I know all these names we use are pretty arbitrary. The cove I'm thinking of is next to the beach area if you make a left when entering West Bank Park.

Care to share that map?

 

[Flightlead]

My experience with GPS and with shooting bearings (extensive) leads me to believe that shooting the bearings is best. D - think the best "primary" to establish would be a datum point on the beach. Assuming we would need to do this over multiple days I think the way to fix the beach datum point would be to mark two widely spread apart spots on the street above the beach with a shot of paint then establish crossing bearings to intersect at a point on the beach. Then we'll put a stake in at that point for the period we are there. Now, I'm good at navigation but I'm not a surveyor so I'm open to suggestions here.

 

[JCDdiver]

Do you have an image of the cove map JCDiver? If so, could you post it?

thanks,

David

We are working on it still. We just dove the cove last weekend.