Gallimaufry: News and Events from the British Dam Society

The biennial British Dam Society prize competition was held in 2013. Engineers under the age of 35 were invited to submit a paper on a dam- or reservoir-related topic for consideration. Seven papers were received from which a shortlist of four was selected for presentation. The final was held at the ICE on 18 November. The four finalists were asked to present their papers and respond to questions from the audience. The standard of presentation was very high and the scoring between the finalists was close. The final result was as follows.

• Winner: Chris Vyse, Llyn Alaw reservoir post-tensioned anchor installation.

• Runner-up: Andy Courtnadge, Worth Farm flood detention reservoir – challenges during construction.

• Highly commended: Andrew Thompson, Tube-a-manchette grouting at Upper Rivington reservoir; Marika Tietavainen, Scour valve replacement.

Mention should also go to the following papers that were submitted for the prize.

• Myron van Damme, On the erosion of the downstream slope of dams and embankments.

• David Scopes, Development of Louth flood alleviation scheme outline design.

• Kate Speirs, MMB reservoir safety improvements.

Four of the papers submitted for the prize are published in this edition of Dams and Reservoirs. All of the entrants are to be congratulated on the quality of the written papers that were submitted. Thanks also go to the judges: Ian Hope, Andrew Pepper and Jonathan Butterworth.

The results of the 2013 photography competition were announced at the BDS prize meeting on 18 November.

A total of 40 entries were received from 27 people. The photographs were judged for the technical accomplishment, composition and impact. Three judges were selected from the BDS committee, together with an external professional photographer

• Stuart King

• Alex Topple

• Matthew Atyeo

• Jo Hughes.

The judges did not know the identity of the photographers during the judging process.

The winners were

• 1st: Marika Tietavainen, Redmires middle reservoir

• 2nd: Graham Yarwood, Old Mill reservoir

• 3rd: Tom Pendrey, Blyderivierspoort dam, South Africa.

The finalists (best 12) and the winning photos will shortly be added to the BDS website and the latter will also be used for the front cover of Dams and Reservoirs in forthcoming issues.

The 82nd annual meeting of ICOLD will be held in Bali in Indonesia between the 1st and 6th June 2014.

There is a symposium – a forum to exchange ideas as well as the technical meetings of the committees and the annual meeting where the management of ICOLD takes place.

The themes of the symposium are

• social and environmental aspects of dams

• engineering issues in dam development

• challenges in tailing dams projects

• dams and water quality management

• catchment area management for sustainable dam development

• challenges in dam safety policy and implementation

• dam operation in connection with climate change.

There are a large number of dams in Indonesia and pre- and post-conference tours are arranged to see some of these dams and also to see some of this beautiful country.

Indonesia has been building dams for decades and since early in the twentieth century more than one thousand dams have been constructed, including 130 ‘large’ dams as defined by ICOLD. These dams have made a huge contribution to the development of the region and the people's welfare. Indonesia has a development plan as their population increases, which includes the construction of many more dams.

More than 1000 delegates are expected to attend the meeting and once again ICOLD is trying to encourage young engineers to attend.

It would be good to see a large British contingent at ICOLD's 82nd annual meeting.

Dr A. K. Hughes

The BDS committee has decided to financially support members who represent BDS on the ICOLD technical committees. Representatives are appointed by the BDS main committee and are expected to play an active part in ‘their’ committee and to attend all meetings of that committee.

BDS will contribute a total of £300 per annum towards each representative's expenses on receipt of a full report in a form ready for publication in Dams and Reservoirs. This report should confirm attendance at the annual meeting of ICOLD, detail the work of the committee and outline the content and progress of any bulletins. The report should be submitted to the BDS technical secretary who may ask for additional information before publication. The ‘main’ meeting of each technical committee is either at the annual meeting or during the congress (which occurs every 3 years).

BDS members who would like to become a member of an ICOLD committee should indicate their interest to the BDS technical secretary stating which committee they would like to join, with a statement that their employer will support them financially and allow time to attend the ICOLD annual meetings and congresses around the world.

The committee on hydraulics is a well-established ICOLD committee and its present task is preparing a bulletin on spillways and spillway hydraulics. This is being carried out under the chairmanship of Brasil Machado of Brazil and aims to produce an update on those issues since the previous ICOLD bulletin on the safe passage of extreme floods. It is hoped that a complete final draft will be ready by the next 2014 ICOLD meetings, leaving a further year for review and comment with eventual finalisation and confirmation for publication in 2016.

There is representation on the committee from a wide range of countries and good state-of-the-art overviews are expected on a number of specialist topics. These will include rock scour under high head jets (being led by Switzerland); labyrinths and PK weirs (being headed by Australia); the relative merits of physical and computerised (CFD) modelling of spillway hydraulics (being headed by the USA); and the use of vortex shafts and tunnels for high head energy dissipation. This last section is being headed by Russia but with significant inputs from recent Chinese experience.

Dr Peter Mason is the UK member of this committee and represents the BDS. He will be making particular contributions to the section on stepped spillways following the recent Environment Agency-funded research work which he headed into the failures of the Ulley and Boltby spillways in the UK. Although these were masonry spillways, there are lessons to be learned which would also be applicable to modern concrete spillways.

Peter Mason

This is a newly formed ICOLD committee under the chairmanship of Professor Jinsheng Jia of China and with Michel Lino of France as the deputy chair. It has been formed separately to the committee on concrete dams to deal with emerging technologies involving cemented materials which cannot be described as manufactured concrete, whether traditional or roller compacted.

One of these has been termed ‘hardfill’, which is a form of soil-cement and which the Japanese have also developed under the terminology of cement–sand–gravel or CSG. The material typically has a much lower strength than concrete, generally in the order of 5 MPa, and also much lower elastic and plastic moduli than concrete. It has lent itself to trapezoidal dam profiles where an upstream sloping dam face attracts significant vertical water load. This counter-balances the horizontal thrust on the dam and produces very low and evenly distributed compressive foundation stresses. This in turn makes it suitable for much weaker foundations than would be the case for a traditional concrete dam. The material can also resist significant overtopping without erosion.

Dr Peter Mason and Dominic Molyneux of the UK were both part-time attendees at the initial meeting of this committee and Dr Mason made a presentation on the Can-Asujan faced symmetrical hardfill dam in the Philippines which he designed and which Mr Molyneux supervised between 2003 and 2004. This was based on the presentation made by Dr Mason on the same dam at a BDS evening meeting on 8th October 2007. The presentation was well received and the UK has applied for a place on the newly formed committee.

Presentations were made on similar structures by representatives from the USA, Japan, France, Turkey and China. Some formalised, if embryonic, guidance has been prepared by both Japan and China on this form of construction. However, it became clear that while there are many similarities in historic approach there have also been some subtle differences, hence the formation of the new ICOLD committee. To summarise, this is seen as very useful and relevant.

One other unusual form of cemented materials dam was presented by a delegate from China. This involved stacking largely single-sized boulders, approximately 300 mm in diameter, within forms in 2 m lifts and then filling the voids by pouring super plasticised, self-levelling concrete. The delegate gave some examples of its successful use in China including areas where reinforcement had also been incorporated. Eventual net cement contents are low (approximately 80 kg/m³) and the boulders absorb much of the heat generated by the setting cement, giving net temperature rises on hydration as low as 4–6°C. (In some ways the technique has much in common with the ‘Colcrete’ grouted aggregate approach used in the UK in the 1950s but developed on a larger scale and using more advanced materials.)

The intention of the newly formed committee is to summarise the above experience in terms of a high-level overview of experience and practice rather than necessarily specific recommendations, and to have this in place by 2016.

Peter Mason

So this year the ICOLD conference was in Seattle, bringing to mind ‘Sleepless in’ and Microsoft for starters. Tom Hanks has my vote since, as a self-confessed technophobe, for me going to a city that also spawned Google, Amazon and Facebook is equivalent to a seal swimming into a group of transient orcas (and David Attenborough has shown us the macabre results of that).

Mr H. and I duly arrived in Seattle following a 2-week holiday in Vancouver, slightly disgruntled at having had a packet of wildflower seeds from Butchart Gardens confiscated at the US border – the perennial Maltese Cross seeds were OK, why?!

Seattle is a big place so having found our apartment near Pike Place Market, I was looking forward to the ICOLD city tour we were joining on the Sunday afternoon to get our bearings. We were registered very efficiently and one of my goodies was a lovely blown-glass bauble, which is wonderful – when we travel, we bring back a souvenir that can go on the Christmas tree, so this is perfect.

Setting off promptly on our tour, there were a lot of one-way streets and it was very busy, so I was glad Ian wasn't driving. Our first stop was the iconic Space Needle, which despite being built for the 1962 World's Fair still looks futuristic; it was definitely on our list for Ian's free day on Saturday before we flew home. Next door was the EMP (Experience Music Project) which we'd heard about from a Canadian we were chatting to on the gondola up to Whistler's Peak. The building from the outside is fantastic, so it would be interesting to see the inside as well.

We carried on to the Hiram M. Chittenden locks where we had another exodus to gaze into the muddy waters and excitedly spot the salmon returning from 3 to 5 years out at sea to the same place where they were spawned, to lay their own eggs and then die. Even when the locks were first built in 1917, they included a fish ladder (a series of steps to allow the fish to travel the height of the lock), which was then rebuilt in 1976 to increase the number of steps from 10 to 21, to make it easier for the fish. A viewing area showed the fish in the ladder and gave an indication of the speed of the flow and how hard the fish have to swim to get upstream – amazing determination.

Monday evening brought the welcome reception and, from last year's event in Kyoto, I was at least familiar with the vast numbers of people attending. The Americans had obviously been forewarned of the capacity of ICOLD attendees for a ‘wee tipple’ and we were therefore issued with two drinks tickets each (I think some of our antipodean friends may have explored the use of a photocopier! (only kidding!)). Being a city venue it was inevitably different to Kyoto as there wasn't any outside space to host a drummer or dancing Geikos, but there was a good variety of nibbles, healthy crudités with dip and a divine assortment of seafood, which we greatly enjoyed. An opportunity to catch up with previously made friends and colleagues, we ended the evening in the bar with Pete and Peggy from New Zealand.

After some exhausting sightseeing, Wednesday evening arrived with the cultural evening at SAM, the Seattle Art Museum. Not being fans of modern art, we approached with an open mind. As we expected it was a busy event, but we collected a glass of wine and mingled for some nibbles, which were very nice. Unfortunately, as it was so busy, by the time we had mingled, chatted and listened to the excellent band blast out a few numbers there wasn't enough time to go upstairs and see more of the exhibition, so we were limited to the vintage cars in the lobby area, some of which were suspended overhead with ‘light sabres’ protruding through them; some were also on the floor, which unfortunately Ian didn't appreciate as the staff had to ask him to move his wine glass when he rested it on the bonnet of a piece of art!

Thursday bought the day of technical tours and I'd put my name down for the day trip to the Cowlitz dam. When we'd registered, I was advised that the start time was 8 a.m., so I arrived at 7.45 only to be told the bus had gone! However, it was actually quite advantageous (with Ian engrossed in more workshops for the day). I was on my own and a full day on ‘dam-watch’ wasn't really my ideal day, so luckily there was space on the half-day visit to the hydro-electric plant at Snoqualmie Falls, which is a local beauty spot in its own right and the site of the first hydro-electric plant in northern USA, built in 1898. It's currently coming to the end of a refurbishment project, so it was interesting to hear the challenges – for example, building temporary dams to protect the workforce while rebuilding the works housing. There were also more modern challenges of balancing the needs of power generation with environmental considerations, ensuring the waterfall maintains its appearance for tourists – there are nature trails to assist wildlife and birds, and the technology of the plant supports river life, especially salmon returning to spawn – and ensuring the Native American tribe of the area, the Snoqualmie, maintain their historic rights to the area which has religious and traditional significance – see, I did learn something! I was then back at the venue hotel in time to join Ian for a spot of excellent lunch.

Friday brought the finale with the farewell dinner and it didn't disappoint. Donning our glad rags we joined our antipodean friends for a most enjoyable meal, drinks and entertainment. Ian presented his friend Shane with a bright, fluorescent orange pair of gloves to improve the Australian cricketers' ‘hand–eye co-ordination’. Unfortunately, they appear to have worked too well as we then lost the next Ashes series – cheers Ian!

After the meal we graced the dance floor; I dare not describe Mr H.'s antics, but sadly our sightseeing the next day was slightly limited by his inability to walk far due to a sprained ankle. We still enjoyed a tour round Seattle's ‘underground’, which if you get the chance is well worth seeing; in essence the city was initially built on a flood plain, so, when rebuilt after a fire, was raised by a full storey, but the old ground level still exists as basements under the street, a fascinating insight into the city's history.

Flying home after a great trip, we can only wait and see what the next ICOLD conference brings.

Mrs Jo Hope

Small Hydroelectric Engineering Practice by Bryan Leyland, CRC Press, Leiden, the Netherlands, £99·00, 254 pp.

The book is full of gems of wisdom borne out of 50 years' experience in the hydro industry along with a ‘Kiwi can-do’ attitude and a natural tendency to ‘think outside the square’.

Bryan is well known within the New Zealand hydro industry for his innovative solutions to specific problems, many of which are discussed in detail in the book. Hydro engineers and developers often refer to his work as an example of the importance of using practical thinking to solve complex engineering issues.

Through his ongoing work and consultancy on hydro schemes worldwide, Bryan has been able to detail the latest developments and proven best practices within the industry. I found the section on Coanda screen intakes particularly useful for my own hydro scheme and have modified my intake designs to incorporate them.

Small Hydroelectric Engineering Practice takes you from start to finish through the evolution of a hydro scheme. From initial site assessment, hydrology, environmental, banking and finance through the many layers of detailed design work for intakes, penstocks and powerhouses to detailed analysis of the many types and configurations of turbine plant and generators available.

Small Hydroelectric Engineering Practice is a thoroughly readable and enjoyable book for anyone interested in small hydro. It is an essential book for anyone working with small hydro, whether a first-time developer or an experienced hydro engineer.

Review by Dave MacKay, Inchbonnie Hydro.

Small Hydroelectric Engineering Practice is an essential engineering reference book that belongs on the desk or bookshelf of planners, engineers, constructors or operators of small hydropower projects.

In addition to being a practical guide to small hydropower technology, this book also discusses the philosophy, planning process and potential pitfalls of small hydro development in a very straightforward way with many examples drawn from the author's lifelong career in the industry.

The challenge of small hydropower engineering is to develop cost-effective project solutions for each unique site with only limited resources. Many of the technical problems that must be identified and solved on large projects also must be addressed on small projects, but without large teams of engineering experts and substantial budgets. So the small hydro engineer needs to be a ‘Jack of most trades’ who is familiar with a wide range of issues using a blend of technical analysis, engineering judgment, advice from equipment vendors and constructors, engineering judgment and hard-earned project experience successfully to plan and implement the project.

Mr Leyland's book is a valuable technical resource and source of advice written in a very easy-to-read way with many helpful examples, photographs and illustrations. It describes how to assess the important characteristics of a small hydro project site. It then discusses conceptual design, refinement of the engineering design of the project, equipment procurement and development of technical specifications and bid documents.

Since Mr Leyland's own engineering background is mainly in mechanical and electrical engineering, the body of the book focuses on small hydro generation and operating equipment including turbines, generators, electrical systems, mechanical systems and the equipment aspects of hydraulic structures such as intakes, spillways, canals and penstocks.

As a true small hydro engineer, he also discusses important civil, hydrology, geotechnical and environmental aspects of small hydro development and provides references to other technical resources in these areas. The chapter devoted to lessons learned from plant failures is also extremely valuable – candid information about what happened and why is often very hard to find.

In addition to the discussion of small hydropower engineering issues in the book, Mr Leyland provides a series of useful tools including spreadsheets, computer software, reference engineering drawings, technical papers and other technical references on plant optimisation economic analysis, financial analysis and contract documents which are also valuable resources for the practising small hydro engineer.

The included archive of engineering drawings from seven completed small hydropower projects in New Zealand is another rare and valuable resource for the small hydro engineer. These drawings show design details of typical small hydro intake gates, gate hoists, steel penstocks, penstock bifurcations, a typical small powerhouse arrangement, control systems schematics and a typical electrical single line diagram from a series of small medium-head hydropower plants. The drawings illustrate innovative solutions to design of custom equipment for small hydro projects and the overall level of detail needed to communicate the design to equipment suppliers and construction contractors.

In summary, Small Hydro Engineering Practice is a worthwhile addition to my ‘A’ list of small hydro engineering reference documents. The combination of straightforward engineering guidance, practical experience, interesting anecdotes, lessons learned from failures and a collection of useful engineering tools makes it a very worthwhile investment.

Review by John P. Christensen P.E. Principal, Christensen Associates Inc.

Details of forthcoming events are listed on the BDS website http://www.britishdams.org/meetings.asp.