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CIRIA and The Ecology Consultancy are working together to develop a Working with wildlife mobile application based on the toolbox talks, species and habitat briefings, to help construction professionals utilise the guidance on construction sites. 5 Marine monitoring The marine monitoring programme that has been implemented at London Gateway is the largest in Europe. The programme has been approved by the Port of London Authority, the Environment Agency and Natural England. The investigations analyse morphological change to the seabed, flow rates, and sediment transport. Hydraulic modelling works began in 2001 to predict how the construction and operation of the port will affect the estuary. Monitoring began in 2003 and will continue during the operation of the port, including both bathymetric and LiDAR surveys. Currently, the monitoring results have aligned with, or been more positive than, the predictions of the hydraulic modelling. Historic and archaeological assets The archaeological assets within the estuary range from early paleo-historic landscapes in the outer estuary through to wrecks of ships and a rare German World War II aircraft. A unique marine archaeological programme has been implemented to investigate and conserve this asset. Surveys were carried out using side-scan sonar, multi-beam bathymetry and magnetometry to identify ‘anomalies’ on the seabed. Diving expeditions were used to examine and map significant wreck sites. Many of the artefacts recovered during these investigations are now on display in local museums and the Cory Environmental Centre. One of the most common finds were unexploded ordnance (UXO). There were 150 found in total, all of which were disposed of through onsite controlled explosions. Part of the German aircraft recovered during the marine archaeological investigations Biological resources Biological surveys have been carried out since 2003 to monitor the health of the estuary and to assess the impact of the construction and operation of London Gateway. Analysis of the community composition allows comparison between seasons and years. A range of species were observed, including Dover sole, skate, herring, cod, brown shrimp, whelks, cockles and range of benthic fauna. The results show that any species affected by the dredge have recovered quicker than expected and that, in general, the biological communities found in the Thames Estuary have been unaffected. Fisheries liaison Since the beginning of the project relations have been developed with local fisheries. The fisheries liaison group has formed a channel in which to communicate with the local fishermen so that they can be informed of the works involved with the project and how these may affect their businesses. From these discussions a fisheries compensation scheme was established so that those whose businesses had been affected by the works can make a claim for any loss of earnings or damage to equipment as a direct result of the London Gateway operations. Terrestrial aspects Alongside the marine works there were also a number of obstacles to overcome on the footprint of London Gateway. The site has had an extensive history from salt extraction during the Iron Age, through air raids during both World Wars, to an oil refinery up until the late 20th century. When Shell decommissioned the refinery in 1999 the site was left to develop into a haven for wildlife. There were many buildings left on the site and the ground was heavily contaminated with carbonbased compounds. An example of some of the contamination encountered during the early days of the project Ecology Surrounded by sensitive sites London Gateway had to ensure that good practice was adopted to minimise impacts on the local wildlife. Before any construction could take place on the site one of the largest ecological translocations in the country had to take place. It took 23 Natural England licences and over 50 ecologists working on the site to move more than 320 000 animals (including lizards, water voles, grass snakes, adders and newts) to new homes in Essex and Sussex. Since the ecology programme began 57 newt ponds have been dug, eight newt tunnels have been installed and approximately 200 ha of new habitat has been created. This includes the creation of new mudflats for wading birds and other wildlife, to compensate for lost habitat during the reclamation for the new berths. To the west of the port is Stanford Wharf Nature Reserve, a new 30 ha wetland habitat, created from a pea field purchased by DP World. A new sea wall was built, and the old wall was then breached to purposefully flood the pea field. The process was carefully designed and monitored using hydraulic modelling. Biological surveys have been carried out to determine the success of the mudflat. Results have been very positive, with evidence to suggest colonisation of new marine invertebrates, juvenile fish and increasing numbers of wading birds. A newly installed newt tunnel linking the receptor sites with London Gateway The second intertidal mudflat, called Site X, is programmed to be completed in 2015. The selected site is opposite London Gateway on the southern bank of the CIRIA guide Unexploded ordnance (UXO) a guide for the construction industry (C681) sets out a defined process for the management of risks associated with UXO from WWI and WWII aerial bombardment. It is also broadly applicable to the risks from other forms of UXO that might be encountered on construction sites. Visit www.ciria.org for details


evolutionwinter2013
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