Approaches to Grand Port Chart No. 2530 General Information Position and Function 11.168 1 Grand Port (20°23'.60S 57°43'.50S), an extensive natural harbor, indents the SE side of Mauritius between Pointe d’Esny(20°25'.64S 57°43'.53S) and the coast W of IIe des Roches (20°17'.61S 57°49'.42S). The harbor affords extensive anchorage but only small craft can berth alongside. Topography 11.169 1 Bambou Mountains rise over the NE coast with spurs extending to the shores of the harbor which is frigned with a coastal reef in places. The low-lying coast to the SW is occupied by the city of Mahebourg (20°24'.52S 57°42'.50E), which straddles the mouth of Rivire la Chaux. To the N, several islands lie close to the coast which is low. 2 The shallow waters of the bay are further reduced by large coastal reefs which surrounded both entrance points and which are separated from a central off-shore reef by N and S channels which give access to the area of the bay between the reefs and the shore. Approach and entry 11.170 1 Grand Port is approached direct from sea and can be entered through Southern Entrance (20°24'.40S 57°46'.00E) or Northern Entrance (20°18'.15S 57°49'.45E). Limiting Conditions Depths and draught 11.171 1 Southern Entrance channel: depth 10 m or more over a least width of 13/4 cables at the inner end. Northern Entrance channel: depth 10 m or more over a least width of 21/2 cables at the inner end. Danish Entrance channel (20°20'.00S 57°49'.45E): this channel is narrow with a bar across the entrance, at which point there is a depth of 4.9 m over a least width of 13/4 cables. This channel should only be approached with extreme caution; see 11.174. 2 Channel between entrance: controlling depth 6.1 m over Jonchee Bar (20°22'.04S 57°45'.77E). This channel is only navigable by vessels drawing not more the 5.8 m. Tidal levels 11.172 1 At Vieux Grand Port, MHWS and MHWN about 0.7m; see Admiralty Tide Tables Volume 3. Abnormal Water levels 11.173 1 Tides at Grand Port are much influenced by the wind. During strong SE winds the HW stand, at and near Mahebourg (20°24'.52S 57°42'.50E), sometimes lasts for several hours. Local weather 11.174 1 The harbor entrances are exposed to the full force of the South-east Trade Wind and consequent ocean swell. This makes Danish Entrance (11.171) unusable as the sea generally breaks right across it and, even when calm, rollers sometimes come in without warning, breaking right up the channel. For Southern Entrance conditions see 11.178. Arrival information 11.175 1 Pilotage. There are no pilots for Grand Port. Local Knowledge. Navigation of the channel between the harbour entrances requires local knowledge and good light in which to see the dangers. Quarantine. See 1.48 regarding the granting of partique. Harbour General layout 11.176 1 Grand Port is formed between the coastal reef and extensive detached reefs which lie up to 3 miles offshore and shelter the harbour. Within the detached reefs there are numerous shoals and coral heads, so that the clear navigable space within the harbour is limited to widths of 5 cables or less. Between these dangers, the positions of which are best seen on the chart, a channel leads NE/SE through the harbour. Towards the NE end, shoals almost close the channel at The Narrows (20°20'.50S 57°47'.00E). 2 There are a number of small jetties and piers on the shores of the harbour which can only be approached by boat on account of the reefs and banks which border them. Mahebourg (11.169), the principal town of the district, stands at the SW end of Grand Port while the town of Grand RiviereSudEst (20°17'.38S 57°47'.13E) is situated at the N end. Seaplane area 11.177 1 An area used for aircraft moorings (20°22'.15S 57°44'.38E) is situated close SE of a jetty at Bois des Amourettes (11.192). Mariners are cautioned to maintain a good lookout for aircraft manoeuvring in the area. Natural conditions 11.178 1 Tidal streams. See information on chart 711. In Southern Entrance the movement of water is nearly always outwards, caused apparently by the water forced over the reefs escaping through this channel. An in-going tidal streams may cause still water while an out-going stream against the South-east Trade Wind, when blowing strongly, may attain a rate of ½ kn. In Northern Entrance, both in-going and out-going streams are fairly regular but vary a good deal in rate, though never strong. 2 Seas are very high and break heavily in Southern Entrance during and, for a time, after strong SE winds, notwithstanding that the depths are considerable. However, after passing llede la Passe (20°23'.93S 57°46'.03E) they subside into a heavy swell in the channel, although breaking heavily over the reefs. 3 During prolonged observations over a period of 4 months the seas, though often very rough off Southern Entrance, were seldom seen to break inside, and never to any height except over the reefs. The general character of the seas was such that, at any time during this period, almost the smallest vessel could have entered safely. Directions Principal marks 11.179 1 Landmarks: Stranded wreck (20°26'.61S 57°44'.02E). Cathedral, Mahebourg (20°24'.71S 57°42'.41E). Lighthouse, white (disused) (20°23'.75S 57°46'.64E), on lle aux Fouquets. Red cliffs (20°23'.01S 57°42'.16E), at La Terre Rouge. Mont Saint Martin (20°21'.2S 57°41'.1E), a conspicuous saddle-shaped hill, 278 m high. Chimney (20°21'.73S 57°42'.38E). 2 Red Cliffs (20°22'.66S 57°43'.06E), at Treize Cantons. Lion mountain (20°21'.74S 57°43'.57E), near the SW extremity of Bambou Mountains. The outline includes lion’s Head, 33/4 cables SE, which resembles the Sphinx, facing inland. Water tower, prominent (20°21'.77S 57°44'.29E). Bunglow (white with black roof) (20°21'.39S 57°44'.56E). 3 Remarkable black rock on the summit of Pointe du Diable (20°20'.21S 57°46'.65E), a bluff, 100 m high, forming the end of a spur from Bamboo mountains. Mont Bambou (20°19'.17S 57°45'.00E) and, in this vicinity, The Thumb, 11/2 cables E, which is a remarkable upright column of stone, 544 m high. Also Voltaire’s Face, 1 cable N, a peak 575 m high so- called due to its likeness to Voltaire’s profile when seen from E and N of Pointe du Diable. 4 Mont Villars (20°18'.82S 57°45'.33E). A distinctive peak when viewed from E and N of Pointe du Diable. Chimney (20°16'.54S 57°46'.99E), prominent, in Beau Champ. Passage across approaches 11.180 1 From a position SSE of Pointe d’Esny (20°25'.64S 57°43'.53E). seaward of the rock, awash, 11/4 miles SSE of the point, the track leads generally NE passing: SE of Laverdie Spit (20°25'.03S 57°46'.32E). which is almost continuoally marked by breakers, keeping in depths more than 20 m to avoid the rollars that can occur in more shallow waters, thence: 2 Across the approach to Southern Entrance (20°24'.77S 57°47'.15E), thence: Not less than 1 mile SE of lle aux fouquets(20°23'.75S 57°46'.64E), thence: 3 Not less than 1 mile outside a reef extending nearly 41/2 miles NE from lle aux Fouquets to Danish Entrance (20°20'.00S 57°49'.45E), the seaward edge of which the sea always breaks heavily, although sometimes appearing appearing quite calm close to the reef.The track outside the reef passes seaward of a group of small islands and dangers consisting of lle aux Fous (20°22'.97S 57°47'.26E), iie Marianne, 11/2 cables NE of lle aux Fous, and a 7.9m shoal, 4 cables farther E. Thence: To a position E of Danish Entrance (20°20'.00S 57°49'.45E). 11.181 1 Useful marks: MauritiusInternational Airport aero light (20°26'.02S 57°40'.53E). Ile de la passe (20°23'.93S 57°46'.03E), which is covered with ruined fortifications and on which there is a tower. 11.182 1 Danish Entrance to lle des Roches. From the position E of Danish Entrance the track now leads generally N, passing: E of a bank(20°18'.93S 57°50'.85E) extending seawards from the reef with depths of 16.5 m or less, thence: Across the approach to Northern Entrance (20°18'.15S 57°49'.45E), thence: To a position E of lle des Roches (20°17'.61S 57°49'.42E) (11.187) Approach to Southern Entrance 11.183 1 Caution. No attempt should be made to enter Grand Port at night. The Southern Entrance is best approached before mid-day when the dangers can be seen from a high vantage point. 2 Soundings. Off Southern Entrance the 200m depth contour lies nearly 2 miles from the reefs fronting Grand Port. In Poor visibility sounding is a good guide to their proximity. Clearing bearings. Approaching Southern Entrance from S, a bearing of not more than 340° of lle aux Fouquets old lighthouse passes ENE of Laverdie Spit (11.180) 11/4 miles S of the lighthouse. 3 Approaching from the NE, the bearing 234° of the old lighthouse passes SE of the detached reef, fronting Grand Port, and clear of the 7.9m shoal, mentioned at 11.180. lle aux Fouquets should be passed at a distance of at least 1 mile. Entry- southern Entrance 11.184 1 Leading marks. From a position about 5 cables ENE of Laverdie Spit the alignment (313°) of the centre of lle de la passé (20°23'.93S 57°46'.03E) (11.181), with the summit of Lion Mountain (11.179),31/4 miles NW,leads into Southern Entrance. 11.185 1 When lle aux Fouquets old lighthouse bears 002° a vessel should keep in mid-channel, passing: Ne of laverdie Point (20°24'.97S 57°45'.76E), this being the E extremity of a reef forming forming the W side of the channel, the edge of whichis a narrow dtrying ridge where the sea always breaks heavily, thence: 2 ENE of a beacon (tripod with staff and triangular topmark)(20°24'.32S 57°45'.50E) (position approximate), thence: WSW of lle de la Passe (20°23'.93S 57°46'.03E) (11.181), thence: Between Jacolet Point (20°23'.80S 57°45'.46E) and Annanas Bank (20°23'.60S 57°45'.87E), thence: Between a depth of 9.8 m (20°23'.54S 57°45'.44E) and a 4.6 m shoal (20°23'.23S 57°45'.70E), thence: 3 Rounding a buoy (20°23'.47S 57°45'.42E) to port, thence: N of a concrete beacon (white pyramid, 3m in height, diamond topmark) (20°23'.54S 57°45'.24E), thence: S of a concrete beacon (red cylinder, 3m in height, triangular topmark) 1 cable S of Piment point (20°23'.16S 57°45'.00E), the W extremily of the central offshore reef at Fer a Cheval Spit, thence: 4 NNE of a concrete beacon (20°23'.45S 57°44'.72E)(red cylinder, 3 m in height, ball topmark), thence: To a position NNE of Olive Bank (20°23'.35S 57°44'.60E), which extends N from the coastal reef. Approach to Northern Entrance 11.186 1 Northern Entrance is best approached in a good light when the edges of the reefs on both sides of the channel are easily seen. Leading line. The line of bearing, about 256°, of Mont Bambou (20°19'.17S 57°45'.00E) leads to Northern Entrance passing over, or close to, an 18.3m patch (20°18'.55S 57°51'.00E). 2 Cautions. The 100m depth contour lies approximately 3 miles off Northern Entrance with a fairly regular decrease in depth up to the entrance but there is rapid shoaling at the edge of the reefs extending towards the channel. See also caution at 11.183. Entry – Northern Entrance 11.187 1 The line of bearing, 238°, of Lion Mountain (20°21'.74S 57°43'.57E) (11.179) leads in through Northern Entrance, passing: 5 cables SE of lle (llot) des Roches (20°17'.61S 57°49'.42E), which is rocky and marked by a beacon, thence: 2 1¼ cables, NW of a 5.5 m shoal (20°18'.39S 57°49'.51E), thence: Close SE of a 12.5 m shoal (20°18'.28S 57°49'.14E), thence: To a position 1 miles SSW of lle des Roches. 11.188 1 From this position, the line of bearing 028°, astern, of lle des Roches leads SSW in mid-channel, passing: Close WNW of a shoal (20°18'.84S 57°48'.83E) depth of 11.3m, thence: 7½ cables WNW of lleFlamand (20°19'.35S 57°49'.30E), a sandy cay, awash at HW, which continually alters its form. 2 The track then leads to a position 5 cables NNE of Diamant Reef (20°19'.70S 57°48'.26E) which is easily seen, especially in the morning, and over which the sea breaks almost continually. From this position the line of bearing 240°of the head of the bluff at Pointe du Diable (20°20'.21S 57°46'.65E) (11.179) now leads in mid-channel to a position 2 cables NW of Brisant Point (20°19'.80S 57°47'.85E) which is usually easy to see, especially in the morning. Berths and services BaieFer a Cheval 11.189 1 Anchorage may be obtained in 11 to 16 m, sand and coral, on Annanas Bank(20°23'.60S 57°45'.87E) with the SW extremity of lle de la Passe (20°23'.93S 57°46'.03E) (11.181) bearing about 161° and lle aux Fouquets old lighthouse (11.179) bearing about 102°. This is the first place where a vessel can shelter within Southern Entrance. 2 Channel north of Jacolet Point (20°23'.80S 57°45'.46E), formed by a small break in the coastal reef, through which boats can generally pass, although the sea may be breaking heavily over the reef on either side of it. For vessels anchored on Annanas Bank, 4 cables ENE, this channel is a useful means of communication with Mahebourg. Small boats can pass inside the edge of the reef, keeping a good lookout for coral heads easily seen in smooth water. Landing can be effected on the W point of lle de la Passe. West end of Grand Port 11.190 1 Anchorage may be obtained N of Perit pate(20°23'.36S 57°43'.78E) in 13 to 16 m, in the position shown on the plan, noting a 7 m shoal, 11/4 cables S of the berth. This is the most frefrequented anchorage in Grand Port and is indicated by the bearing 304° of PiltonMarron (20°21'.96S 57°41'.90E), open SW of Mont Saint Martin (20°21'.42S 57°41'.52E). Its W limit is indicate by the bearing 000° of Lion’s Head (20°21'.94S 57°43'.79E). 2 Small vessels may anchor in 15 m, 2 cables SSW pate, in the position shown on the chart. Useful marks: Beacons on Le Matcasse(20°23'.51S 57°43'.02E). Beacon on Buff’s Reef (20°23'.20S 57°42'.74E). 3 lle Singe (20°22'.99S 57°42'.86E). lle Chat (20°22'.95S 57°42'.95E). If the beacons at the W end of Grand Port are in place and can be seen, they are sufficient guide for anchorage. Mahebourg 11.191 1 Landing. This is best effected at Race Jetty (20°24'.23S 57°42'.59E). With a power- driven vessels a small boat should be used as a tender as there is little water off the jetty. Supplies.Fresh Provisions are available. Bois des Amorettes 11.192 1 Anchoragemay be obtained in about 20m, off Bois des Amourettes(20°22'.10S 57°44'.20E), as shown on the plan. A vessel approaching this berth from Southern Entrance should pass between the W extremity of Fer a Cheval Spit (20°23'.00S 57°45'.00E) and a shoal with a least depth of 3.7 m (20°22'.75S 57°44'.32E). See 11.177. Useful mark: Water tower (20°21'.77S 57°44'.29E). 2 Berth. Jetty at Bois des Amourettes. A dolphin, 1½ cables E of the jetty, marks the end of a submarine pipeline laid NNW to a small jetty near a tank farm. Supplies. Fresh water is laid on to the jetty but it should be boiled before consumption. Jonchee Bar 11.193 1 Anchorage may be obtained in about 18 m in a spacious bay in detached reef 7 cables E of Jonchee Bar (20°22'.04S 57°45'.77E), as shown on the chart, but this berth can only be reached with local knowledge. Point du Diable 11.194 1 Anchorage is available, as shown on the chart, in about 20 m, mud, with Pointe du Diable(20°20'.21S 57°46'.65E) (11.179) bearing about 261° distant 5 cables. Tazar Point 11.195 1 Anchorage for small vessels may be found in about 8 m, 2½ cables NNW of Tazar Point (20°19'.20S 57°47'.28E). When approaching this anchorage a beacon on Tazar Point should be rounded at a distance of about 1 cable. The anchor should be let go nearer the W side of the reef than the shore, as shown on the chart, so that with the prevailing SE wind, a vessel will ride in mid-channel where the sea is quite smooth. 2 It is reported that a vessel entering with a foul bottom and lying in this berth for a few days will leave perfectly clean. Channel north. A boat channel leads N from this anchorage towards the mouth of Grande RivireSudest(20°17'.38S 57°47'.13E), across which a ferry operates. The channel is marked by beacons.