Port Phillip Bay Fieldwork July 2009
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PORT P HILLIP B AY F IELDWORK JULY 2009 MARITIME H ERITAGE U NIT HERITAGE V ICTORIA CONTENTS Introduction 1 William Salthouse fieldwork 3 Clarence fieldwork 6 City of Launceston fieldwork 9 Conclusions 12 Appendix I – Dive logs 13 FIGURES Figure 1 – Sand levels around William Salthouse . (measurements are in cm.) Figure 2 – William Salthouse Site plan with photos Figure 3 – Clarence site plan with exposed timber heights Figure 4 – Clarence site plan with exposed timber heights and photographs Figure 5 – Updated site plan for SS City of Launceston Figure 6 – Updated site plan for SS City of Launceston with photographs Introduction Fieldwork was undertaken between 6 th July and 10 th July 2009 in Port Phillip Bay by Heritage Victoria (HV) staff in conjunction with volunteers, under the supervision of Hanna Steyne. All diving took place from the HV boat Trim , skippered by Peter Harvey, Hanna Steyne and Russel Stewart. All diving was undertaken using scuba equipment to AS2299 and DCIEM tables were used. Diving was undertaken by Peter Harvey, Hanna Steyne, Rhonda Steel, Darren Kipping, Des Williams and Karolyn Gauvin. This report was written by Rhonda Steel, Darren Kipping, Karolyn Gauvin and Hanna Steyne. The fieldwork could not have taken place, and would not have been successful, without the support and assistance of our volunteers. Thanks go to Russel Stewart, Des Williams and Karolyn Gauvin. The main aims of the fieldwork were to undertake monitoring work on William Salthouse , Clarence and City of Launceston . These three sites are protected under the Victorian Heritage Act 1995 and all three lie within Protected Zones. William Salthouse is one of Victoria's oldest and most important wrecks, sinking in 1841. It was the first merchant vessel to sail between Canada and Port Phillip and was flouting British Navigation Laws when it did so. It is archaeologically significant for its evidence of ship construction, cargo stowage and cargo types. It is educationally and recreationally significant as the wreck of an intact wooden merchant ship with its early cargo intact. Monitoring work on the William Salthouse by HV in September 2008 and observations by recreational divers in February 2009 identified a significant change in the stability of the sand dune supporting the wreck, specifically the level of sand covering the artificial Cegrass matting. The aim of this fieldwork was to survey the exposure of artificial Cegrass using the same methodology as in September 2008, and also to place six fibreglass poles around dune to better monitor the sand levels in future. Clarence is significant technically and archaeologically as an example of an early Australian-built vessel. The schooner was built in 1841 on the Williams River in northern NSW. Clarence was a small wooden schooner, 50 feet in length and 60 registered tons. The Clarence was employed as an inter- colonial trade vessel. In September 1850 the vessel was on its way to Melbourne with a cargo of sheep. It ran aground on the east bank of the Coles Channel in Port Phillip. Whilst the cargo was recovered, the vessel became a total wreck. Most ships built in Australia during this time were constructed by rule of thumb, without using models and plans. Clarence has been investigated by HV and research indicates the vessel has unique construction techniques indicative of early Australian ship building. Clarence has been identified as a suitable site for a national research project aimed at investigating both Australian shipbuilding and in-situ preservation methods for shipwrecks and shipwreck relics. As preliminary work for this 1 proposed project, this fieldwork aimed to collect baseline information about the sites current condition, levels of exposure and sand cover around the site. In addition, four fibreglass poles would be placed around the site in order to accurately monitor sand levels around the site prior any future disturbance work associated with the national research project. City of Launceston is one of Victoria's most significant shipwrecks. The City of Launceston was a 277-ton steamship designed and built by Blackwood and Gordon of Glasgow in 1863, for the Launceston and Melbourne Steam Navigation Company. It was built specifically for the Bass Strait passenger trade between Melbourne and Launceston, with accommodation for eighty- four saloon and ninety-four steerage passengers. In November of 1865, the City of Launceston collided with the 500-ton steamship Penola and sank in the central part of Port Phillip Bay. The discovery and reporting of the City of Launceston and subsequent lobbying of the State Government led to the proclamation of the State Historic Shipwrecks Act 1981 . It is one of the most intact iron steamship wrecks of its age in Australian waters, is technically and scientifically significant for the remains of its engine and boiler, and evidence of the experimental salvage attempts using Patented Maquay hydrogen gas generating devices. The City of Launceston is archaeologically significant for its high level of preservation with evidence of its cabin fittings, passenger’s luggage and cargo. In late June 2009 HV engaged Professional Diving Services to attach five 80kg zinc anodes to the City of Launceston in attempt to slow the rate of corrosion of the hull and structure, and prevent the collapse and dispersal of the site. As part of this work, divers from Professional Diving Services photographed a spiral staircase and glass lamp chimneys not previously seen on the site. Work on the City of Launceston as part of this fieldwork aimed to assess any changes on the site, map out any new features that had become exposed. The anodes were to be inspected and mapped. An additional piece of work undertaken was to take GPS positions for the William Salthouse, Clarence , City of Launceston , and Joanna as part of work to re-gazette all Protected Zones within Victoria in WGS84. The Joanna is currently buried under approximately 2m of sand. 2 WILLIAM SALTHOUSE FIELDWORK Using a methodology developed in 2008, the length of exposed Cegrass fronds was measured around the site. By plotting the rough location of measurements, a general plan of sand levels around the site was developed (Figure 1). Six fibreglass rods were hammered into the sand dune around the site with two at the bow, two midships, and two at the stern area. These are marked with identification tags and will act as permanent markers to measure sand deposition and erosion in the future. Day 1 06/07/2009 A buoy was set over the site while divers waited for slack tide. Rhonda and Des first entered the water at 14:30 to measure frond heights on both port and starboard sides of the vessel (Figure 1). Rhonda also drew rough sketches of exposed timbers and barrels. Darren and Hanna entered the water shortly after to measure frond heights around the bow area (Figure 1). Peter and Karolyn went in the water 35 minutes later for site orientation and bearing measurements. William Salthouse lies roughly on a 150° bearing, later clarified using buoys at either end of the wreck. Day 2 07/07/2009 A buoy was set over the site while divers waited for slack tide. Peter and Des went in first at 14:30 to hammer in the 6 fibreglass rods. Darren and Hanna followed 20 minutes after to measure in the rods to the wreck site; distances between rods and height of rods from the seabed (Figure 1). Hanna also took photographs of the site. Rhonda and Karolyn entered the water 40 minutes later to finish frond height measurements of the stern area (Figure 1). It is clear that scouring and erosion continue to have a significant effect on the site. Cegrass fronds are still exposed around the site at varying lengths, with a steeper bank at one end than at the other. There were exposed sections of steel mesh (the bases for the Cegrass mats) at both ends. The most significant change since September 2008 and February 2009 is the dramatic scouring in the middle of the wreck exposing ships timbers, barrel cargo and animal bones across most of the site. There has also been some loss of sand and hull timbers around the edge of the site as plank were visible down the sides of the sand dune. The exposure of the central part of the wreck is particularly worrying as the intact nature of the cargo is one of the reasons the site is so unique and significant. The loss of barrels and cargo contents is a major problem and will need to be addressed. The obvious solution would be to cover the central area with Cegrass matting, however this would render the site of little interest to recreational divers. Given that, currently, a maximum of 20 divers visit the site per year, this may not have a significant negative impact on relationships with recreational divers. 3 Figure 1 – Sand levels around William Salthouse . (measurements are in cm.) 4 Figure 2 –William Salthouse Site plan with photos 5 CLARENCE FIELDWORK The aim of this dive inspect the wreck for changes in sand cover and timber exposure, as well as placing fibreglass poles for future monitoring of site stability. Day 3 08/07/2009 The team arrived at the Clarence protected zone around 13.00. Coordinates for the site were checked the previous day when conditions enabled the wreck to be seen from the surface. The site was relocated, a buoy was set and Trim was roped to the protected zone post while we awaited slack tide. Divers entered the water at 14.30. Pete and Des were first in the water and hammered 3 fibreglass rods into points around the wreck.