CAUTION TO BE USED IN RELIANCE UPON AIDS TO NAVIGATION.

THE AIDS TO NAVIGATION DEPICTED ON CHARTS COMPRISE A SYSTEM OF FIXED AND FLOATING AIDS TO NAVIGATION WITH VARYING DEGREES OF RELIABILITY. PRUDENT MARINERS WILL NOT RELY SOLELY ON ANY SINGLE AID TO NAVIGATION, PARTICULARLY A FLOATING AID TO NAVIGATION. WITH RESPECT TO BUOYS, THE BUOY SYMBOL IS USED TO INDICATE THE APPROXIMATE POSITION OF THE BUOY BODY AND THE SINKER WHICH SECURES THE BUOY TO THE SEABED. THE APPROXIMATE POSITION IS USED BECAUSE OF THE PRACTICAL LIMITATIONS IN POSITIONING AND MAINTAINING BUOYS AND THEIR SINKERS IN PRECISE

GEOGRAPHICAL LOCATIONS. THESE LIMITATIONS INCLUDE, BUT ARE NOT LIMITED TO, INHERENT IMPRECISIONS IN POSITION FIXING METHODS, PREVAILING

ATMOSPHERIC AND SEA CONDITIONS, SLOPE OF AND THE MATERIAL MAKING UP THE SEABED, THE FACT THAT BUOYS ARE MOORED TO SINKERS BY VARYING LENGTH OF CHAIN, AND THE FACT THAT THE BUOY BODY AND/OR SINKER POSITIONS ARE NOT UNDER CONTINUOUS SURVEILLANCE, BUT ARE NORMALLY CHECKED ONLY DURING PERIODIC MAINTENANCE VISITS WHICH OFTEN OCCUR MORE THAN A YEAR APART. DUE TO THE FORCES OF NATURE, THE POSITION OF THE BUOY BODY CAN BE EXPECTED TO SHIFT INSIDE AND OUTSIDE THE CHARTED SYMBOL. THE MARINER IS ALSO CAUTIONED THAT BUOYS MAY BE EXTINGUISHED OR SOUND SIGNALS MAY NOT FUNCTION AS THE RESULT OF ICE, RUNNING ICE, OR OTHER NATURAL CAUSES, COLLISIONS, OR OTHER ACCIDENTS. FOR THE

FOREGOING REASONS, A PRUDENT MARINER MUST NOT RELY COMPLETELY UPON THE POSITION OR OPERATION OF FLOATING AIDS TO NAVIGATION, BUT WILL ALSO UTILIZE BEARINGS FROM FIXED OBJECTS AND AIDS TO NAVIGATION ON SHORE. FURTHER, A VESSEL ATTEMPTING TO PASS CLOSE ABOARD ALWAYS RISKS COLLISION WITH A YAWING BUOY OR WITH THE OBSTRUCTION THAT THE BUOY MARKS.

b. Generally, this special notice shall be the first Local Notice to Mariners of each new year. Those Districts having a regular and a seasonal/summer boating season may delay

publishing the Special Local Notice to Mariners until the start of the boating season. c. Each District shall mail an electronic copy of the Special Local Notice to each of the

other Districts.

C. Format of the Local Notice to Mariners. 1. General.

a. The Coast Guard's Integrated Aids to Navigation Information System (I-ATONIS) shall be used to generate the Local Notice to Mariners.

b. The I-ATONIS system-generated cutoff date for Light List information being included in each LNM is midnight Tuesday (Wednesday AM). LNMs shall be generated and dated each Wednesday. Districts shall submit LNM to NAVCEN no later than 1800 (local district time) every Wednesday.

c. Each notice shall be numbered consecutively during the calendar year.

d. A notice stating that questions or inquiries about the Local Notice to Mariners should be directed to the District (dpw) shall be included on the first page.

e. Pages shall be numbered "Page 1 of 6", etc., at the bottom of each page. Enclosures may be numbered separately.

f. Information in the notice shall be arranged in the same geographical sequence as the Light Lists with the exception of the Chart Corrections. This shall apply equally to channel reports, bridges, notice of regattas, reports of obstructions, designation of danger areas, etc.

g. Sketches or reproductions of portions of charts on which information concerning changes in aids to navigation are indicated may be included in Local Notices to Mariners when they will assist the mariner in interpreting the data more easily. Reproduced chart portions must be annotated with the statement "NOT TO BE USED FOR

NAVIGATION." They may be prepared and included for, but not limited to, the following:

(1) When aids to navigation are relocated to facilitate dredging operations. (2) When a number of changes are made in a locality at the same time. 2. Abbreviations.

a. The following standard abbreviations will be used in the Local Notice to Mariners. These abbreviations are consistent with agreements between National Ocean Service (NOS), National Geospatial-Intelligence Agency (NGA), and standards established by the International Hydrographic Organization (IHO) and International Association of Marine Aids to Navigation and Lighthouse Authorities (IALA).

b. All Local Notice to Mariners items concerning oceanographic data buoys (ODAS)/ (NOAA weather buoys) shall include the notation (ODAS) in the buoy name. The

abbreviation (SPM) shall be included in all items concerning lighted single point mooring buoys used by tankers.

EXAMPLES:

Al - Alternating MHz - Megahertz

bl - blast Mo - Morse Code

bu - blue Oc - Occulting

C - Canadian ODAS - Anchored Oceanographic Data Buoy Dbn - Daybeacon Q - Quick

ec - eclipse R - Red

ev - every RACON - Radar Transponder Beacon F - Fixed Ra ref - Radar reflector

fl - flash s - seconds

Fl - Flashing si - silent

G - Green SPM - Single Point Mooring Buoy I - Interrupted SS - Sound Signal

Iso - Isophase W - White kHz - Kilohertz Y - Yellow Lt - Light

3. Sequence.

a. The following sequence of sections shall be used in the Local Notice to Mariners. (I) Special Notices

(II) Discrepancies - Discrepancies Corrected

(III) Temporary Changes - Temporary Changes Corrected (IV) Chart Corrections

(V) Advance Notices (VI) Proposed Changes (VII) General

(VIII) Light List Corrections

Additional Enclosures, including Publication Corrections

b. Questions on the format should be directed to Commandant (CG-54131) or NAVCEN. Headquarters, NAVCEN, and District staffs shall work closely together on this matter. 4. Accuracy.

a. Accuracy is of prime importance in the positioning of an aid to navigation and the reporting of that position.

(1) A complete set of charts (digital or paper) for a District's area of responsibility shall be maintained. These charts shall be kept up-to-date from information supplied by units doing the aid to navigation work.

(2) Prior to advertising a new position, positioning results shall be reviewed by district staffs in accordance with Chapter 4 of Aids to Navigation Manual – Positioning, COMDTINST M16500.1 (series). Coordination between the positioning staff and the marine information staff is essential.

b. Before a notice is issued, all information shall be checked and proofread by someone other than the person preparing it initially.

c. It is imperative that the position of new fixed structures be determined to an accuracy required by its accuracy standard (See section 5.C.1 of Aids to Navigation Manual – Positioning, COMDTINST M16500.1 (series)). When a Local Notice to Mariners is issued for a High Level of Accuracy aid as outlined in the Aids to Navigation Manual – Positioning before a post-construction survey can be completed, the notice shall be based on the best information provided by the reporting unit and shall include "position

approximate (PA)." A subsequent notice shall be issued after the survey indicating the accurate position and the PA removed.

d. Chart correction positions shall be listed using degrees, minutes, and seconds to three decimal places (thousandths).

e. The assigned position of an aid to navigation shall be the position specified on the CG- 3213 and advertised in the Local Notice to Mariners. Any time an aid to navigation is permanently relocated, the new assigned position must be advertised, regardless of how minor (small) the change.

f. Positions shall be listed in the Light List corrections using degrees, minutes, and seconds to three decimal places (thousands).

g. Any questions that may arise concerning entries or the format of the Local Notice to Mariners shall be referred to NAVCEN or Commandant (CG-54131) prior to publication. 5. Purpose and Content of Each Section.

a. Special Notices.

(1) The purpose of the Special Notices section is to allow the District the latitude of promulgating information of a special nature that affects the marine environment. (2) In this section, reference to Armed Forces gunnery exercises, pyrotechnics drills,

night photography, changes in regulations pertaining to pilotage, and other operations affecting marine traffic can be announced.

(3) The format of the Special Notices should be edited to provide simple, to-the-point, information.

(4) If the information is of a specific nature where geographic positions are required, start the paragraph with the state (island, territory), followed by general location,

(offshore, bay, etc.), then the specific location (river, channel), followed by the message. These geographic references immediately alert the user to the general location of the action being taken. If additional positioning information is required for charting purposes, the chart number for the largest scale chart of the area shall be added for ready reference. A chart correction may also be required.

b. Discrepancies - Discrepancies Corrected. This section contains a tabulation of all discrepancies to aids to navigation and those which have been corrected from the last published list. A discrepancy is any change in the status of an aid to navigation that is different than what is charted and/or published in the Light List. Where a corrected discrepancy affects information published on the charts or in the Light List, an appropriate correction must be written.

(1) The BNM reference column under Discrepancies is to be used to list the first time the discrepancy is announced in a BNM. The LNM Start (LNM St) column is used to indicate when the discrepancy was first advertised in the LNM. The LNM End (LNM End) column is not used.

(2) The BNM reference column under Discrepancies Corrected is to be used to list the BNM in which the correction was announced. The LNM Start (LNM St) column is used to indicate when the discrepancy was first advertised in the LNM. The LNM End (LNM End) column is used to indicate the LNM in which the correction was announced.

(3) Only the largest scale chart on which the discrepancy appears on shall be listed. (4) An aid that is damaged should not be listed as destroyed unless the aid is completely

destroyed or is leaning at an angle greater than 45 degrees. An aid that can be repaired without replacing the structure should not be listed as destroyed.

(5) Range lights may create unique circumstances because a structure may serve as a support for two different aid functions. Perhaps the most common example is a range structure that displays an omnidirectional light shown from the range lantern or a separate lantern. If a range light is arranged so that it produces, in addition to the beam on the channel axis, an all-around light of lower intensity, care must be taken when advertising a discrepancy. If the lantern displaying the beam on the channel axis is extinguished, the range should be advertised as operating at reduced intensity on rangeline. If the omnidirectional light is extinguished, the light should be

advertised as visible on rangeline only. EXAMPLES:

DISCREPANCIES

LNR Aid Name Status Chart No BNM Ref. LNM St LNM End

65 Southwest Pass Light RACON INOP 11361 1124-03 02-04 75 Cat Island Pass LWB CI EXTINGUISHED 11357 51-04 03-04 L

1 1

28380 Brownsville Channel Range Front Light REDUCED INT ON 11123 58-04 04-04

RANGELINE

24055 Baytown Bend Range Front Light VISIBLE ON RANGELINE 11328 77-04 05-04

ONLY