View of the coral ledge where the cable will land in Madang
From the beaches to each of the Cable Landing Stations in Madang, Guam and Sydney, the shore end surveys scrutinize the beach environments where PIPE’s cable will land.
Engineers have been performing periodic inspections at each of the landing sites to assess changes in environmental conditions such as beach erosion and other external hazards. The inspections form part of local government permitting requirements.
Where possible, shore end engineers perform their inspections following earthquakes or wild weather to determine any impacts to the integrity of the cable system or changes in the seabed.
Our engineers have been comparing the as-built records against actual inspection data to identify any discrepancies and update changes in shore end cables. Common changes needed to the original drawings are new cable crossings, changes in burial depth due to sand migration, and new cables in shared manholes.
The following are extracts from each of the survey reports.
Extract from the Madang Report:
There are no charted obstructions to the landfall except coral reefs and beach rocks in the vicinity of the area. The area immediately in front of the landfall point is shown on the Admiralty charts as “UNSURVEYED” (approximately up to the 100 meter contour, which is approximately 300 metres offshore).
Extract from the Guam Report:
Minor beach deposits, reef limestone, and alluvium of Holocene age occur along the coastline. These deposits cover a small percentage of the surface of Guam, and may be as much as 70m thick at the mouths of some rivers. The beach deposits are composed of poorly consolidated sediments, mostly calcareous sand and gravel thrown onto beaches by waves but some deposits of volcanic sand can be found where streams drain volcanic uplands. Reef limestone up to 4m thick also occurs locally. Deposits of alluvial clay fill stream valleys and cover the inner parts of coastal lowlands.
Extract from the Sydney Report:
The proposed landfall is situated on a high energy ocean beach in a wide east facing bay. The seabed slopes away relatively sharply to approximately 18 m, approximately 0. 5 nm from shore. The seabed up to this contour is mostly fine to medium grained golden colored sand with 10% to 60% shell. Some reef rock is exposed close to shore towards the northern end of the bay. Due east of the bay, between the 20 and 40 m contour (0.5-1.5 nm from shore) is an expanse of exposed reef rock. There are at least three sandy (medium to coarse grained orange sand with 40% shell) channels. The rocky promontory of Long Reef continues underwater eastwards beyond 3 nm from the coast. The gradient of the seabed beyond the band of exposed reef rock becomes gentler, obtaining a water depth of 50 m at 3 nm from the shore. The seabed composition is coarse sand continuing eastward, gradually blending into fine grained grey colored sand with 5% to 20% mud and 30% to 40% shell.