Great Sandy Strait Northbound Transit Guide (Wide Bay Bar → Urangan)
Great Sandy Strait Northbound Transit Guide. A northbound transit of the Great Sandy Strait is built around clearing the southern depth gate at South White Cliffs / Ungowa with enough tide height, managing the stream through Garry’s Anchorage Narrows, and timing Sheridan Flats for workable depth before exiting toward Urangan. Unlike the southbound run, the bar crossing occurs first, and the tide curve must be used to ride the flood into the Strait rather than fighting the ebb.
The southern Strait is the controlling section for deeper yachts, with depths at LAT commonly between 1.8 m and 2.0 m. The northern Strait is more forgiving, but Sheridan Flats still requires attention for vessels drawing 1.8–2.0 m. The Great Sandy Strait Northbound Transit Guide below follows the natural northbound sequence and is written for skippers who want depth‑aware, practical navigation guidance rather than general commentary.
1. Wide Bay Bar →
Southern Strait Entrance
This leg establishes your entry into the Strait and sets the timing for the first depth gate. After crossing Wide Bay Bar on the first of the flood, vessels enter the southern Strait with the tide running in. Depths in the inner channel are generally 2.0–3.0 m at LAT, but the margins dry extensively. The bar crossing dictates your start time, and the goal is to ride the flood northward. The southern entrance can feel exposed in swell, and skippers maintain a conservative line through the marked channel. Once inside, the water flattens quickly, and the Strait’s character becomes apparent.
2. Southern Strait
Entrance → South White Cliffs
This leg positions you for the first depth‑critical section and allows you to assess tide height and stream strength. Depths remain 2.0–3.0 m at LAT, with the channel narrowing as you approach South White Cliffs. The stream can run hard here, especially during springs, and the bends require accurate positioning. This is where you confirm whether the tide is rising as predicted and whether you are early or late for the depth gate. Skippers often reduce speed to ensure arrival at South White Cliffs with adequate tide height. The channel edges fall away quickly into drying banks, so tight alignment with the marks is essential.
3. South White
Cliffs / Ungowa (Depth Gate #1)
This is the first controlling depth point northbound and must be taken with adequate tide height and manageable stream. Depths are typically 1.8–2.0 m at LAT, and the channel can shoal after strong weather. For yachts drawing 2.0 m, this is a half‑tide rising minimum. For 1.8 m draft, +0.2–0.4 m is workable but still conservative. The stream accelerates through the bends, and shallow water amplifies its effect. Skippers avoid low water and peak stream. The channel edges drop into drying banks, and the bends require positive helm control. Once clear of this section, the Strait becomes more forgiving, and the pressure on tide height reduces.
4.
South White Cliffs → Garry’s Anchorage
This leg provides depth relief and gives you the option to pause before committing to the northern flats. Depths improve to 2.0–3.0 m at LAT, and the channel becomes more defined. Garry’s Anchorage lies just off the main channel and provides reliable holding in sand and mud with protection from most directions. Many skippers use Garry’s as a staging point if they are early for Sheridan Flats or if the tide curve does not align cleanly. The anchorage is calm, predictable and well‑positioned for a controlled northbound run. If continuing without stopping, this leg allows you to reassess tide behaviour and adjust speed accordingly.
5. Garry’s
Anchorage Narrows (Stream Gate)
This section is governed by stream strength rather than depth, and timing determines vessel control. Depths are 2.5–3.0 m at LAT, so depth is not the constraint. The narrows accelerate the tidal stream, especially during springs, and the bends require accurate helm control. Transit at slack or early flood/ebb depending on direction. Northbound vessels often meet southbound traffic here, so skippers maintain a listening watch and announce intentions on VHF 16/73. Anticipate set in the bends and avoid over‑standing into the shoals on the inside of the turns. Once clear of the narrows, the Strait opens again and becomes easier to manage.
6. Garry’s
Anchorage → Sheridan Flats
This leg positions you for the second depth gate and allows fine‑tuning of your tide window. Depths remain 2.5–3.0 m at LAT until the flats. This is where you confirm whether the tide is rising as predicted and whether you are early or late for the next gate. Several temporary anchorages exist along this stretch, allowing you to pause if needed. The channel edges fall away quickly, so skippers maintain tight alignment with the marks. This leg is often run at reduced speed to ensure arrival at Sheridan Flats with the correct tide height. The flats are broad and shallow, and the channel is not deeply cut.
7. Crossing Sheridan Flats (Depth Gate #2)
This is the second controlling depth point northbound and must be timed with the correct tide height. Depths are typically 1.8–2.2 m at LAT in the marked channel. For yachts drawing 2.0 m, this is a mid‑tide or better transit, ideally on a rising tide. For 1.8 m draft, low water is possible but tight, and most skippers still prefer mid‑tide for margin. Crossing at or near slack water avoids strong stream in shallow water, which can push the vessel sideways toward the banks. Sounder readings fluctuate here due to soft mud and sand, so skippers watch for trends rather than reacting to every dip. Once clear of Sheridan Flats, the remainder of the transit is straightforward.
8. Sheridan Flats
→ Round Island Channel
This leg transitions you from the shallow northern flats into deeper, more forgiving water. Depths improve to 3–4 m, and the channel becomes more predictable. Afternoon sea breezes can create short chop across the open water north of the flats, but conditions ease once inside the more confined channels. The marks must still be followed precisely, but the risk of grounding reduces significantly. This is where skippers often increase speed slightly and prepare for the final approach into Urangan.
9. Round Island
Channel → Urangan
This final leg completes the transit and returns you to dredged, marked water with consistent depth. Depths are 3–4 m in the dredged channel leading into Great Sandy Straits Marina. The approach is straightforward, with minimal hazards. Fishing traffic increases near the marina entrance, and skippers maintain a careful watch. Once inside the marina, the transit is complete, and vessels can refuel, reprovision or wait for the next weather window.
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Great Sandy Strait Northbound Transit
Guide Summary
The Great Sandy Strait Northbound Transit Guide is a tide‑timed sequence built around clearing South White Cliffs / Ungowa and Sheridan Flats with enough water under you, using Garry’s Anchorage as a flexible staging point, and riding the flood into the Strait after crossing Wide Bay Bar. With accurate tide interpretation, disciplined channel‑keeping and conservative timing, the Strait becomes a predictable, depth‑reliable passage for yachts drawing 1.8–2.0 m. The Great Sandy Strait Northbound Transit Guide with practical information for a passage north.