Greenock/Gourock/Port Glasgow Drainage Scheme and Long Sea Outfall Design

The paper describes the design and construction of a comprehensive drainage scheme which is based on a system of intercepting sewers, headworks, and a long sea outfall. Details are given of the fabrication, discharge arrangements and construction of the outfall, together with measures used for long-term protection of the pipeline. The layout and design of the headworks and the changes made to the original design to meet changing environmental requirements are given. The paper briefly outlines the existing sewerage system and goes on to describe the proposed interceptor sewerage system for the connection of the flow from the existing outfalls to the headworks. Difficulties encountered in construction are highlighted.
The authors indicate their view on the suitability of the present design, and recognition is given to the likelihood that additional facilities may be required in future. The difficulties which could arise in the provision of such facilities are also highlighted.     

Hastings and Bexhill Drainage and Sea Outfall Schemes

THE DEVELOPMENT OF the Hastings and Bexhill drainage systems since the early 1960s is described. Most of the 18 million investment has taken place in the last decade in several phases which were completed in 1988. Ultimate disposal of sewage is by long sea outfall. The new works include two pumping stations and rising mains leading to a header tower serving the outfall. A number of innovations are included to overcome technical problems and reduce costs. The paper concludes with some comments on operational aspects of the new works.     

Reconstruction of British Nuclear Fuel's Drigg Marine Outfall

In 1985 the House of Commons Environment Committee expressed reservations over some of the waste-management procedures followed by British Nuclear Fuels Ltd at their Drigg low-level radioactive waste disposal facility near Sellafield in Cumbria. These reservations prompted the company to implement a £20 million programme of improvements aimed at maximizing site usage, reducing trench leachate arisings and redirecting to the Irish Sea.
This paper provides information and test results associated with design considerations and initial dilution testing, respectively, of a computercontrolled long sea outfall system designed to discharge leachate to the Irish Sea. Information is also provided on difficulties experienced during construction of the outfall.     

海底超长距离钢筋砼顶管施工技术与应用

本文介绍了 1 60 0口径、长 1 856m污水排海管道一次连续顶进到位的施工应用技术 ,阐述了顶管施工的主要设备系统的选型、污浆减摩、顶进施工等关键技术。     

Effect of the EC Urban Wastewater Treatment Directive on Marine Treatment Practice

The EC Directive on urban wastewater treatment will have a considerable impact on the methods used for the treatment and disposal of sewage at coastal locations. The Directive requires the natural processes involved in marine treatment to be enhanced by the use of land-based treatment to meet the same standards.
This paper discusses the implications of this change, in particular the problems involved in constructing and operating conventional treatment plants at coastal locations. Planning problems, both locally and on a catchment basis, are considered. It is concluded that these difficulties point to a need for new thinking in catchment planning and in the design and construction methods used for treating wastewaters in coastal communities. This is illustrated with UK and continental examples.
In addition, the implications in terms of outfall design are discussed. It is shown that the change of emphasis towards land-based treatment does not necessarily reduce the need for a high degree of dilution and dispersion in the sea in order to meet environmental standards. As a result, sound planning, design and operation of long sea outfalls remain as important as ever.     

索普瑞玛超长防水卷材及全自动摊铺工艺在青岛海湾大桥工程中的应用

目前为世界第一大桥的青岛海湾大桥地处冰冻海域,气候条件恶劣,对防水防腐具有较高的要求。索普瑞玛200m超长型Antirock路桥专用防水卷材和Macaden全自动卷材摊铺系统,应用于该大桥桥面防水防腐工程中取得了良好的效果,本文具体阐述了卷材的铺贴过程及细部节点处理等问题。     

杭州湾跨海大桥海中平台钢结构施工技术

受海上大风、大雾、大雨等恶劣天气的影响及海中建筑施工场地狭窄的限制,杭州湾跨海大桥海中平台和观光塔施工存在较多难点.通过三种施工方案指标及利弊的对比分析,决定平台采用3台固定式塔吊、观光塔采用外附塔吊的施工方案.同时对实施方案中塔吊安拆及抗风性能进行验算,确定合理吊装顺序、焊接防风措施及测量方案,成功克服了塔吊基础的设置及构件的垂直运输、大风及海洋气候条件焊接等一系列难题,有效保证了钢结构安装进度、质量及安全.     

POLLUTANT BUILD UP & RUN OFF ON HIGHWAYS; EXPANDING THE CURRENT METHODOLOGY FOR ADDITIONAL DETERMINANDS

Pollutants build up on highways and are washed off during a rainfall event; and are usually discharged via an outfall to a watercourse. CIRIA report 142 (1994) guidance for evaluating wafer quality downstream of a highway outfall considers only copper and zinc in the water quality assessment of highway outfalls; determinands thought to occur in significant concentrations in highway runoff. This guidance has since been adopted in the Design Manual for Roads and Bridges environmental assessment. However, recent investigations suggest that other determinands may occur in unacceptably high concentrations. This paper demonstrates that additional determinands should be considered in the water quality assessment downstream of a highway outfall.     

Design of the shield tunnel for the trans-Tokyo bay highway

The Trans-Tokyo Bay Highway project is the first phase of an ambitious plan to connect Kawasaki and Chiba by a 15-km crossing of Tokyo Bay. The crossing involves a 5-km bridge, a 10-km undersea tunnel, and a manmade island in the middle of the bay. The construction method for the undersea tunnel must take into account the large external diameter of the primary lining (approx. 14 m); the extremely soft ground under the sea; the extremely high water pressure to which the tunnel will be subjected; and active seismic conditions in the Tokyo Bay area. This paper discusses the slurry shield tunnelling method adopted for the undersea tunnel portion of the project.     

Ultra-Violet Disinfection of Sewage Effluents: A Pilot Study at Bellozanne, Jersey

In March 1990 a pilot ultra-violet disinfection plant was installed at the sewage-treatment works in Bellozanne, Jersey. The pilot plant was set up to test the ability of the process to meet certain defined objectives and, ultimately, to enable the island authorities to satisfy stringent water quality objectives in the receiving waters of St Aubins Bay.
The pilot study simulated an open channel installation using medium pressure ultra-violet lamps parallel to the direction of flow. The pilot plant was supplied by Trojan Technologies Inc.
The pilot study met its objectives and confirmed the design parameters for a full-scale plant installation to follow.     

杭州湾跨海大桥海中观光塔超高变截面悬挑脚手架施工技术

在杭州湾跨海大桥海中平台观光塔幕墙施工脚手架搭设中,针对海上施工气候条件恶劣、搭设高度高(塔高145.6m)、观光塔体型复杂(哑铃形)、悬挑钢结构生根及安装困难等施工难题,通过采用高空分段变截面悬挑式脚手架搭设、悬挑钢梁和主体钢结构柱通过抱箍连接设计及针对性的安全技术保障措施,实现了该脚手架搭设施工安全、高效、经济的目的。该技术具有安全系数高、经济实用、工期短的特点,成效显著。     

GULLANE OUTFALLS, SCOTLAND

This paper describes design and construction of two new sea outfalls discharging from Gullane Waste Water Treatment Works (WwTW) to Aberlady Bay, on the south side of the Forth estuary (Firth of Forth), 25km east of Edinburgh, Scotland. The outfalls were installed by float and lower, using the Flow-Lay® technique, believed to be a first for steel pipes. The paper also describes air transport, beach movement and soil liquefaction and their effect on pipe stability, material and profile.     

大连星海湾跨海大桥主桥索塔钻孔灌注桩施工

以大连星海湾跨海大桥为例,分析了工程的地质条件及特点,通过勘察海上深水岩溶地层分布特征,探讨了解决岩溶地质钻孔问题的方法,对主桥索塔钻孔灌注桩的施工技术进行了阐述,指出采用该方法成功地完成了施工任务,达到了预期的效果。     

Construction Risk in Coastal and River Engineering

New methods and protocols are presented to assess and mitigate time, cost, quality and safety risks in construction, based upon the research behind two manuals which have been produced by HR Wallingford under industry guidance. The paper focuses on the specific risks associated with weather, sea and river state conditions. The inter-relationship with procurement route and insurance is also discussed. A contractor's view of construction risk is then given in the form of a case study based on the Eastbourne Coast Protection Scheme. This scheme involved work on a coastal foreshore in a tidal and marine environment and included five phases of timber groynes, rock revetments, concrete sea-walls and the reconstruction of promenades plus two phases of shingle renourishment.     

Remediation of polluted surface water outfalls – customer communication and changes in behaviour

Water and sewerage companies are experiencing increased levels of pollution at surface water outfalls attributable to incorrectly installed wastewater pipe work from predominantly domestic premises. Foul to surface water plumbing errors can cause environmental pollution in local rivers and streams, but the remediation of polluted surface water outfalls is sustainable only if undertaken in parallel with stakeholder education. Methodologies developed to date to inform, educate or change customer behaviour regarding misconnections have done little to reduce the problem. This paper reports on a study conducted to identify gaps in customers' knowledge with a view to raising awareness of the issues. It is anticipated that the conclusions drawn will be used to better inform the public about misconnections through effectively targeted communications.     

Design and Construction of the Isle of Dogs Pumping Station

T he pumping station employs submersible pumps to drain surface water from the newly developed Enterprise Zone of the Isle of Dogs, London, and discharges storm overflows from an existing combined sewer system. At full development the nominal capacity of the pumps will be 12 m³/s.
After screening the flow passes to the pump chamber, where 12 main and two sump pumps are located. The main pumps deliver through individual syphon discharge pipes to a high level surge tank, which drains by gravity through a short outfall to the river Thames.
Diaphragm walling was used in the construction of the foundations and underground work. Attractive brick buildings form the pump hall and building housing the high voltage electrical equipment and the transformers. Steel sheet piles protect the river frontage.
The station will operate unattended, and will be controlled automatically by water level sensors. Supervision will be by telemetry links to the Thames Water Authority's (TWA) area control centre at Abbey Mills.     

Use of Mixing Zone to Derive a Toxicity Test Consent Condition

This paper describes how the Clyde River Purification Board (the regulatory authority) and Bee-cham Pharmaceuticals (the identified discharger) agreed and adopted a novel means of controlling a pharmaceutical plant effluent which is discharged to Irvine Bay, Scotland. Control was achieved by means of a consent (licence) condition requiring compliance with a laboratory test of acute toxicity, which was added to the more orthodox conditions already imposed upon the discharge. The new condition was derived using the concept, explicit in the environmental quality objective/environmental quality standard approach to pollution control, of an allowable mixing zone around the outfall. The derivation and validation of the condition necessitated laboratory and field bioassay, current measurements and dye releases, and the use of a plume development model.     

Policies influencing the design of the Richmond transport project

The Richmond Transport Project is one of the last elements of the City and County of San Francisco's Wastewater Master Plan for reducing combined sewer overflows into San Francisco Bay. The project includes a 10,200-ft.-long wastewater storage and diversion tunnel that is currently under construction. The tunnel follows an alignment through a sensitive urban area in the northwest part of San Francisco and traverses portions of the Golden Gate National Recreational Area (managed by the National Park Service), Lincoln Park, the exclusive Seacliff residential district, and the Presidio Army Base. In addition to the tunnel, an underground overflow chamber will be constructed to allow future overflows to be discharged through an abandoned outfall tunnel eliminating overflows at the current outfall located at BakerBeach. Planning activities for the project spanned more than 10 years and involved an extensive public participation process. Public policy issues that influenced the City's approach toplanningand designing this project were: the interactions with the numerous agencies involved; an ongoing public participation process; the development and evaluation of the various project alternatives; design accommodations to minimize construction impacts in this urban area; and discharge modif cations such as the underground overflow chamber system designed to eliminate future wastewater overflows at Baker Beach.     

Monitoring anionic surfactants at a sea outfall, Halifax Harbour, Canada

Anionic surfactants enter the coastal water via untreated sea outfall discharges. A concentration range between 1.0 and 200 μg l⁻¹ can be found in polluted areas. The highest concentration being detected near the point source. In Halifax Harbour, high concentrations of surfactants are associated with the presence of rising plumes. Wind and tidal currents can affect both the spreading of these compounds and the waste field. Under certain circumstances, anionic surfactants may be used as waste effluent tracers but in combination with other parameters.     

Satisfying the Water Supply Demand of the Channel Tunnel

When Europe's largest civil-engineering construction site, the Channel Tunnel, requested a guaranteed source of water during 1988, the Folkestone District Water Company was experiencing the first signs of the drought conditions which were to prevail for the next three years. Whilst infrastructure changes allowed for supplies to be made available to the Channel Tunnel contractors, the increasing reduction of resources meant that an alternative supply of water was required.
The solution to the problem was to utilize desalination by reverse osmosis of sea water taken from the English Channel. The process design and operation of this most arduous of feed water is discussed, demonstrating the successful application of this technology.