Section 17 

 MAYPOET, FLORIDA — U. S. COAST GUAED TRAINIKJ STATION 



AI7.OI Location of the Teat Station and Test Board 



A test "board of the panel type was Installed on June 8, 19M)-, 

 at what was then the U. S, Haval Auxiliary Air. Station, hut Is now the 

 U. S. Coast Guard Training Station, at Mayport, Duval County, Florida. 

 This Station la located on the south hant of the St. Johns Elver, 

 near Its mouth and about 22 miles from Jacksonville. The test "board 

 Is submerged under the main dock at the southwest comer of a dredged 

 turning hasln. In a part of El"bault Bay that Is least affected "by 

 tidal flow. It Is approximately 4,000 ft from the St. Johns Elver 

 proper, and approximately l■^■ miles from the Atlantic Ocean, or ahout 

 2| nautical miles from the end of the channel Jetties projecting Into 

 the ocean at the mputh of the river. The turning "basin is roughly 

 rectangular in shape, approximately 2,250 ft wide "by 5^000 ft long. 

 Access to the St. Johns Elver is gained "by an entrance channel approxi- 

 mately 750 ft wide "by 900 ft long, situated at the northeastern comer. 

 Diis channel, as well as the greater part of the turning "basin, is 

 55 ft deep In its central portion. This test hoard is well protected 

 from storms. 



Because it was not practical to Install the test hoard near 

 xmtreated piling, as req.uested, it was suspended underneath a wooden 

 dock, the piling of which had heen suhmerg^ since December 19^1* 

 and was covered "by a thin Tsamacle coating, ^felrlne horers were 

 reported to "be very active at this location, and keels of "boats were 

 said to have "been eaten away in a 12- to l8-month period. In 19hh the 

 method used to protect vessels at this activity was to install a one- 

 inch worm shoe on the keel and to Insert one thickness of commsrcial 

 felt (tar paper) hetween the worm shoe and the keel. It has "been 

 o"bserved that this method successfully repels marine horers for a 

 period of 90 to 120 days. The horers are reluctant to penetrate felt 

 and will eat horizonteilly eJ.ong the worm shoe Instead of eating the 

 felt. This method has proven hi^ly satisfactory on all types of 

 small "boats, up to and including the 63-footers. 



AI7.02 Hydrographic Data 



The depth of water at the location where the test "board was 

 installed was 19 ft at half tide; the tidal range was approximately 

 6^ ft; the velocity of the current was approxinrately one-half knot, 

 caused solely hy eddies from e'b'b and flow of tide. 



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