Taming the Big Sandy river11 May 1998
To prevent a small US town and thousands of additional home owners falling prey to the threatening waters of the Big Sandy river, the US Army Corps of Engineers is planning to build a flood control dam. Suzanne Moxon explains why financial and environmental objectors are trying to block this flood protection scheme
Located near the Russell Fork, part of the Levisa Fork of the Big Sandy river, the small town of Haysi in Virginia, USA, made its way into the record books in 1977. Haysi has been flooded many times, but the most notable event occurred in 1977 when the waters of the Big Sandy river inundated the town with record flood levels. During 2-4 April 1977, 16.5cm of rain fell in the Big Sandy basin, and in some locations over 46cm was recorded. Three fatalities occurred and, at today’s prices, flood damage was estimated at US$406M. Seven years, later in 1984, Haysi experienced its second-worst flood, which caused damages in the region of US$166M.
After the dramatic scenes of 1977, US Congress passed legislation in 1981 which directed the US Army Corps of Engineers to provide flood protection for the Big Sandy drainage basin. It was stated that such protection must encompass the Levisa and Tug Forks of the Big Sandy river, along with the neighbouring Upper Cumberland basin in Kentucky.
‘Flooding has been a problem in this area for many years. Between 1900 and 1984 Haysi experienced 52 damaging floods,’ Steve Wright from the US Army Corps of Engineers said. ‘However,’ he added, ‘major flood control projects do not develop very quickly in the US.’
It was not until 1996, fifteen years after Congress’s initial actions, that it authorised the construction of Haysi dam, on the Russell Fork near Haysi, for the purpose of flood control. The delay was partly due to the Corps’ resources being dedicated to work on the Tug Fork flood protection scheme. This is nearly completed and now the Corps can concentrate on the Levisa Fork project, which incorporates Haysi dam and an accompanying downstream floodproofing and evacuation scheme. Currently, the Corps of Engineers is preparing an environmental impact statement on the project.
Unfortunately, intense criticism is shadowing proposals for the US$118M Haysi dam. Opponents, which include an organisation called Taxpayers for Common $ense, argue the following points:
•The Corps has already built five flood-control dams in the basin which control 40% of the watershed’s river flow.
•Alternative flood protection plans are much less expensive.
•The project is economically unjustified, only providing protection based on a record flood event of 1977 and in some areas on a 100-year event.
Environmental groups have also voiced their concerns. ‘It’s a terrible project,’ Scott Faber from American Rivers said. ‘There are already a lot of dams in the area and there isn’t much free-flowing water left in the US.’
However, as Steve Wright explained, decisions to build flood control dams are not taken lightly. The geography of the local population and the geography of the region emphasise the important role of flood control measures. ‘Understanding the terrain and the location of the population is important to understand the need to use dams for flood control,’ he said.
Wright explained the geography of the local population in more detail. The Appalachian Mountains offer few areas for construction except narrow river valleys where roads, railroads, individual homes, businesses and long narrow towns are located along streams and rivers. Consequently, in the Levisa Fork basin, people often live very close to the river but are not in clearly defined communities. As a result of this they have limited access to services such as police, fire and rescue which would all play important roles in the event of flooding.
Another important consideration is the geography of the region. Rainfall becomes runoff into tributary streams, and both rivers and streams rise rapidly, inundating infrastructure and buildings.
Although Wright admits that the Corps has already constructed flood control dams in the basin, he says the Haysi dam would be the most effective way to eliminate or reduce flooding for 4700 structures located within the 1977 floodplain.
Haysi dam has been described as the ‘keystone’ of the Levisa Fork flood control project, but floodproofing and floodplain evacuation will also take place. Floodproofing will entail raising existing structures to 0.3m above the 1977 flood level. For floodplain evacuation, properties will be purchased if they cannot be floodproofed due to their structural integrity or if they are more than 3.4m below the 1977 floodplain. ‘It is important to note,’ Wright says, ‘that this is a voluntary programme and some individuals may not choose to be part of it.’ The programme is currently in the planning stages and the first part of the work should start by 2000 in Buchanan County, Virginia.
The Haysi dam will reduce the cost of the floodproofing and evacuation components of the Levisa Fork flood control programme. ‘The construction of the Haysi dam would eliminate 1000 properties from the floodproofing and floodplain acquisition programme, and reduce the level of floodproofing for another 3700 properties,’ Wright explained. ‘The financial benefits of constructing Haysi dam would eliminate the need to spend approximately US$200M on floodproofing or evacuation. Ultimately, the net savings of constructing Haysi (the cost of floodproofing with the dam in place, minus the actual cost of the dam) would be over US$80M.’
Responding to criticism about Haysi dam and the Levisa Fork project as a whole, Wright says that such opposition does not come from those who would live downstream of the structure. ‘In three public meetings held in the summer of 1997,’ he says, ‘there was overwhelming support for the project, probably on a ratio of 99:1. Admittedly, people whose property would be taken by the project are concerned about losing their land but, if they can find similar property in the nearby area, they are willing to relocate.’
Norman Mullins, the Mayor of Haysi, said at one of the public meetings: ‘I have really put a lot of miles on myself running around trying to get Haysi dam going. I am for the Haysi dam because I have lived here and seen the destruction.’ Other local residents described their experiences during Haysi’s most severe flood in 1977: one paralysed man, trying to escape from his house, came ‘within a hair’ of being washed away by the water; another man drowned trying to rescue his pregnant wife; other people explained how they went to the top of the mountains and cried as their houses and belongings were washed away down the river. ‘I think we are lucky that we can move and make room for this dam,’ one resident said. ‘I think that it is one of the most needed things there are.’
Financially, Wright claims that in the 1981 legislation which directed the Corps to provide flood protection, Congress determined that the Haysi dam project was economically feasible. Ninety-five per cent of the cost would come from federal funds and 5% from state funds, with Kentucky and Virginia providing US$2.95M each. Letters of intent to cost-share the project have already been received from the Commonwealth of Kentucky and the State of Virginia.
Critics deplore the fact that federal taxpayers are being lined up to pay for 95% of a flood control project which will only provide local benefits.
However, as Wright comments, the project has not yet been given the go-ahead — Congress needs to appropriate money to kick-start work. ‘At the moment,’ he says when questioned about the lack of federal funding, ‘the project is in doubt.’
The Huntington district of the Corps, which is responsible for building the dam, is keen to get work under way. ‘This will be a very interesting dam,’ Wright said. ‘It’s a double curvature arch dam and we seldom build these in the US.’ Historically, the Corps of Engineers has constructed earthen dams and has only one other structure of this design — the Portugues dam currently under construction in Puerto Rico. So why has this design been proposed for Haysi?
The principle advantage of the double curvature arch dam is this: it evenly distributes the force of the impounded water to the foundation and sides of the dam. This distributed force and strength of the concrete minimises the amount of concrete required for the structure, making it less expensive to construct. Compared with 210,000yd3 of concrete required for a concrete gravity dam, the double arch structure will only require 75,000yd3. Furthermore, the Corps has some expertise: the Portugues dam was designed by an employee at the Jacksonville section of the Corps who, after moving to Huntington, introduced the division to this interesting design.
The proposed Haysi dam will be 65m high, 271m long with a 3m wide crest. It will impound a reservoir of 189ha in the summer, with a maximum pool for flood storage of 351ha.
Although the main purpose of Haysi dam would be flood control, there are additional recreational benefits to be derived from it. These will include recreational activities on the lake and whitewater activities downstream of the dam. ‘Such recreation aspects of the project would be valuable to tourism in an economically depressed area,’ Wright explained.
Once and for all
As the Huntington district of the Army Corps of Engineers continues to assess the environmental impact of Haysi dam, all eyes are on Congress — waiting to see if, and when, funds will be appropriated for the flood control structure.
‘At a time when the accepted wisdom is that that age of dam building is past, we are working hard to construct this dam,’ Steve Wright said. The US Army Corps of Engineers believes that the threatening waters of the Big Sandy river have to be tamed, once and for all.
|The US Army Corps of Engineers|
|In 1802 Congress established a military academy at West Point, New York in the USA. The facility produced engineering officers and was the only engineering school in the USA until 1825. The reputation of the academy’s army officers was enhanced as the school assisted in the development of science and engineering departments at other colleges, such as Yale and Harvard. Consequently, Congress began to use the Army Corps of Engineers for infrastructure development and in 1824 it was given the task of developing navigation on the Ohio and Mississippi rivers, establishing its role as the nation’s water resource manager. Today, the Army Corps of Engineers is responsible for: •Flood control management. •Developing and maintaining inland river and ‘great lakes’ navigation. •Developing and maintaining coastal deep harbours. •Maintaining regulatory responsibilities for wetlands. The Corps is an agency comprising 40,000 civilians and 1000 army officers with military leadership skills.|