ICW Observations and Updates September 2019

23 Sep

SEPTEMBER 26, 2019  UPDATES based on early southbounders are in Italics. 

The following is a list of the known ICW trouble spots.  Several places which are now clear but have historically been a problem are listed here because there are many references to these trouble spots in  ICW guides. Several of these have been dredged recently.  This list will give you updated information and keep those historical trouble spots flagged.  It is likely they will shoal in again. Fortunately hurricane Dorian made no significant changes to the ICW inlet crossings.

Charts are often slow to display updated bathymetry whether it is crowd sourced Navionics Sonar Charts (NSC) or USACE surveys on Aqua Map Master (AMM).  The USCG is generally right on top of the  situation and moves the ATONs promptly, as needed.  If you follow the ATONs through these spots on a rising tide you should be fine.

Mark all these areas on your charts so that you are aware of  places which need to be transited with a little extra care and planning. None of these are dangerous and all of them are in areas with adequate tidal range such that if you wait till the tide is rising you can proceed with plenty of clearance.  Once the tide starts to fall, you should take extra precaution though.  If you stray a boat length or two out of the ICW channel on a falling tide, you may be there for a long time!

AMM and NSC are needed in the ICW.  Off the ICW , in creeks rivers and anchorages, there are no USACE surveys . NSC is the best available information  once you leave the ICW and enter anchorages, and there are hundreds of miles of the ICW without any recent surveys by NOAA or USACE.  NSC charts are essential tools.

  1. Bogue Sound west of Beaufort, NC Bogue Inlet, R12 and R10A STM 211 to 212, There has been a growing shoal through this stretch. The Sonar Charts of Navionics (NSC), and the USACE surveys in Aqua Map Master (AMM) are showing 7’ MLLW, but the channel is shoaling in from the red side. The USACE survey of 03/2019 as shown in Aqua Map Master  (AMM) is advised  for transiting at low tide if your draft exceeds 5 feet.
  2. Swansboro STM 230 No changes. Watch for cross setting currents.  Navionics has best information on anchoring off the town dock.
  3. Browns Inlet STM 239. Dredged but already showing signs of filling in. Follow the ATONs. The USACE survey is June 11. I prefer the NSC here. Southbound stay 50 feet off G61a but more like 100 feet off G63 for the better water.
  4. New River Inlet STM 245. You Must use NSC or AMM through here. Watch out: R72 a has been drifting off station several times.  NSC is best for the Mile Hammock anchorage.
  5. Black Mud Channel, AKA New Topsail inlet, STM 270. Shoal building at G99a Either NSC or AMM will guide you.
  6. Mason Inlet STM 280 Shoal builds in from the east side near 122A. Hug the dock with the boat lifts.
  7. Masonboro Inlet Crossing Stm 285 Recent surveys indicate water is good here.
  8. Whisky Creek area STM 288 Shoal encroaching from ocean side at north of G135 and G137 See NSC here. Charts show an island 0.1 miles north  of 137.   It isn’t there.
  9. Carolina Beach Inlet Crossing STM 292 Shoal encroaching at R154  stay a bit to the east of center.  NSC and AMM both cover it well.
  10. Snows Cut.  Southbound: A major shoal has built it from  the inland side. You must dip well to the south until  you are 500 feet south of G161.  NSC shows it better than AMM but either system will get you past this corner. At the west end of the cut  you must head well south of  R162 and then swing north of G 161a and then south of R162A
  11. Lockwoods Folly Inlet crossing STM 320. The channel dredged this past March 2019 has filled in. Once again you must take the northern route, which has been used most of the past 5 years.  This area has changed rapidly; look for an updated USACE survey in AMM.  Given how rapidly this inlet crossing has changed, more changes are likely since the 8/21/2019 survey. The USCG has moved the ATONs and if you follow the ATONs you should be Ok.  If your draft is over 5’ you will want to cross this section on a rising tide.
  12. Shallotte Inlet Crossing. STM 330 So far so good; it is a straight shot. Follow the ATONs. Be aware that there is a there is a shoal building 81. At this time no charts show that it has encroached on the channel
  13. Estherville Minim Creek Canal. STM 410 North end. Just 400 feet after you enter the canal there is a 6-foot shoal. The USACE survey does not  display well: follow NSC here.
  14. Santee River crossings. There are several shoals building where the ICW crossest the Santee Rivers. NSC and/or AMM will help.  The USACE survey plot is very narrow here.  You will find better water in several places outside the USACE survey.  Follow NSC. As you turn to enter  Four Mile Creek Canal at R18 both the charting systems show a shoal encroaching on the red side.  The channel runs quite close to the shore.  Is quite narrow.  Proceed with caution on a rising tide.
  15. South of McClellanville. STM 430 to 433 This 3-mile stretch is about  the worst section of the ICW.  There is only about 4 or 4.5 feet at MLLW.  We have transited  10  times following the best water  we could find in NSC. It worked well for us.  SEPTEMBER 26, 2019.  There  two dredges working this area. the entire 4 mile stretch will be dredged. https://www.sailfeed.com/2018/04/icw-south-mcclellanville/
  16. Dawho River. STM 498 This section was dredged in 2019. The new channel is very narrow and  the ATON placement does not guide you through it.  We transited in March 2019 .  There is a northern route first proposed by Bob Sherer in early 2018.  We have used that route and find it to be easier to follow with deeper water . NSC can guide you through  the northern route. There is no USACE survey of the northern route.
  17. Ashepoo River and Ashepoo Coosaw Cutoff. STM 513 to 518 https://www.sailmagazine.com/cruising/icw-ramshorn-through-watts-cut.
  18. Hell Gate Dredging in process
  19. Little Mud River STM 653 to 656 Another very shallow section of the ICW we have transited many times using the NSC charts.  The USACE survey yields a similar but not identical route. https://www.sailmagazine.com/cruising/updates-the-icw-north-bound
  20. Jekyll Creek STM 680 to 684 Dredged in July 2019.  No updated charts are yet available from NOAA or Navionics.  The newly dredged channel is only 75 feet wide!  Very likely  will fill in quickly.
  21. Cumberland Dividings STM 704 there is a shoal encroaching at R60. Just favor the green side. https://www.sailmagazine.com/cruising/updates-the-icw-north-bound
  22. South of Fernandina. STM 717. NSC and AMM will work taking you well south of R16. Once you turn the corner at G1 and G1a only NSC will guide you along the western shore.  You must not cross the middle.  The NOAA charts will run you aground https://www.sailmagazine.com/cruising/updates-the-icw-north-bound
  23. Fort George Channel. NSC shows several shoals encroaching on the ICW here.  They are real  shoals building into the channel. use NSC charts. STM 735 https://www.sailmagazine.com/cruising/updates-the-icw-north-bound
  24. Sawpit Creek STM 701-732 Sawpit Creek and Nassau sound had dredging in the spring of 2019. Look at surveys dated 5/2019 or later. Otherwise, the NSC charts have been good help through here.
  25. STM 733 to St Johns River. There are no USACE surveys. There are several shoals encroaching at STM 735, see F  t George channel NSC charts are very good through here.
  26. ICW ST Johns River crossing entering Pablo Creek.  For several years the NSC charts were the only charts which accurately showed this channel. NOAA charts and derivative apps were flat wrong leading to many groundings.  In April 2019 USACE surveyed this section.  Both systems now agree on the best route.
  27. Johns River to St. Augustine. NSC charts are important to avoid shoals: no USACE surveys.
  28. Continuing south on the ICW the NSC charts will give you good guidance. There are no USACE charts except as follows:
  29. Augustine inlet crossing. USACE survey has very limited range.  It only covers about 1 mile and does not even reach the Bridge of Lions.
  30. Fort Matanzas. STM 781. In process of dredging Sept – November 2019
  31. Ponce Inlet. STM 840-842. Recently dredged Shoals may rebuild at R 18
  32. Lucie inlet STM 988. S. Dredging in process late 2019. Use NSC charts or watch for USACE survey dated after September 2019
  33. Jupiter Inlet crossing Stm. 1002: Use NSC charts or USACE
  34. From Jupiter south the only USACE surveys are the commercial shipping inlets and ports. You will find that the NSC charts will  be an important tool all the way to Key West.

In summary.  NOAA is a fabulous resource, however the charts along the Atlantic ICW are can be out of date with inaccurate bathymetry and even some missing ATONs.  To navigate the ICW you need Navionics, and will want to have access to any up to date USACE surveys.  Surveys older than 6 months are less  valuable.  Surveys a year or more old, are highly suspect. Navionics Sonar charts cover the entire ICW and all the rivers creeks and anchorages along the way.  Navionics is not always perfect: The USACE surveys also help in the most dynamic inlet crossings   Navionics is always better than NOAA and an essential tool for Navigating the ICW.

This is the AMM chart of Lockwoods Folly with the USACE survey dated August 18, 2019. The blue dashed line is our track from April 6, 2019  It was straight through the middle of the newly dredged channel. By mid July the shoal was encroaching from the south and the pink route would have kept you in 8+ feet of water through here.  But as you can see after the August 18, survey, the dredged channel is completely filled in and this route is not passable.  The black route shows they best route through here at this time.

 This is an example of a place where NOAA charts and the apps derived from them will completely fail you. This is the ICW at Vero Beach using the most up to date NOAA Chart.

This chart shows the details available from Navionics Sonar Charts in this same location.


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