How should I plan a passage from northern Lombok to Bali given the strong currents?
I'm leaving northern Lombok tomorrow and heading to Bali Marina at Benoa. I understand the currents through Lombok Strait can be strong; how should I choose my departure time and route?
Answer
Plan around the current through Lombok Strait and a daylight entrance to Benoa, allowing time to delay if conditions differ from the forecast. Before setting a departure time, confirm the destination marina, obtain current predictions for your route and check for wind or swell opposing the stream.
Check the stream first
Assuming you mean Bali Marina inside Benoa Harbour, plan the strait crossing and the tidal harbour entrance separately. A favourable crossing does not guarantee a favourable entrance.
Lombok Strait carries a generally south-going Indonesian Throughflow, with tidal streams superimposed on it. Strength and direction vary with position, tidal phase and season; do not assume the whole strait reverses every six hours. Several knots of current can dominate a cruising yacht's progress.
- Use current tidal-stream information or a reputable local current forecast alongside corrected charts and sailing directions.
- Check forecast wind, gusts and swell across the strait and on the southern approach to Bali.
- Ask the destination marina about entrance conditions, recommended arrival timing, berth availability and its working VHF channel.
- Confirm that all predictions use the same time zone: Bali and Lombok use WITA, UTC+8.
High or low water at Benoa does not establish slack water in Lombok Strait. A tide-height app alone cannot tell you when to cross. Without your departure anchorage, cruising speed and dated predictions, a departure hour would be guesswork.
Plot each leg separately
Plot from your departure anchorage, around the Gilis, Medana or elsewhere on northern Lombok. Measure each leg to the Benoa approach rather than taking a straight-line distance to the marina.
For a conventional route west of Nusa Penida, check clearance from its northern and western sides and from Nusa Lembongan's reefs. Do not take a narrow passage between the islands simply to shorten the distance: these passages have their own strong streams and hazards.
A south-going stream may help you make southing towards Benoa, but it can also sweep you below your intended crossing point. Steer to maintain a safe ground track, comparing chartplotter course over ground with heading. Leave room to correct before reaching an island, shoal or traffic route.
Current is sometimes weaker towards the edges of a strait, but headlands can accelerate the flow and produce eddies. Do not hug an unfamiliar reef-lined shore to escape adverse current. Give priority to charted clearance and manoeuvring room.