Who better to tell us what the hot topics are with regard to dams than our readers? Here we present the top 10 most-read dams and civil structures stories of 2013, based on page views at HydroWorld.com.
By Elizabeth Ingram
One significant benefit to the editors of Hydro Review is the ability to track traffic and interest in content posted on our website, HydroWorld.com. We have access to a variety of metrics that tell us what is of greatest interest to site visitors, both in terms of daily news stories and monthly magazine content.
So when I wanted to cover the always hot topic of dam safety in a meaningful way for readers, I turned to the website for help. The HydroWorld.com site is broken down into what we call “topic centers.” One of these covers dams and civil structures. And one of the subtopics under that topic center is dam safety. Every news story or magazine article on the site that relates to that topic will appear under that specific heading, making it easy for visitors to keep abreast of dam safety news in the U.S., Canada and worldwide.
For this article, rather than telling you what I think is “hot” with regard to dam safety in North America, I am going to highlight what site visitors say is hot. Below are the 10 stories related to dams/civil structures and safety that received the most page views in 2013. If you’ve read them, you know why there were popular. If not, numbers from your fellow hydro industry enthusiasts indicate they would be good future reading material!
1. Installing Hydraulic Crest Gates to Improve Flood Control at Hatfield
This article was published in the July 2012 issue of Hydro Review, and it appears to have considerable longevity. The article covers work done at Hatfield Dam in Wisconsin to replace an antiquated and failing flood control system consisting of wooden flashboards atop a gravity spillway. During high flows, the flashboards had to be removed, a labor-intensive task. To replace them often required substantially lowering the level of the lake. The solution chosen involved installing hydraulic crest gates, each of which operates independently and remotely. The gates were tested just two years after completion by the second largest flood on record, and the system operated exactly as designed.
2. San Clemente Dam removal begins with ceremony
Dam removal just seems to be one of those hot button topics. In fact, I blogged about it recently and got a lot of feedback (see “From the Web” on page 79). This June news story details a ceremony held to mark the first day of deconstruction of San Clemente Dam on the Carmel River in California, which was determined to be seismically unsafe and an impediment to steelhead trout and other wildlife. In addition, the reservoir behind the dam was more than 95% filled with sediment, according to The Nature Conservancy. Removal of this dam, said to be the largest such undertaking in state history, is expected to take just over two years.
3. Flooding causing dam safety concerns in Colorado
We try to cover breaking news on HydroWorld.com, with a focus on what it means for our readers. In this case, heavy rains in Colorado in September caused flash flooding in areas surrounding Denver, as well as breaking Meadow Lake Dam and overtopping at least four other dams. The flooding also resulted in two deaths. Officials from nearby Boulder County said water approached the tops of some of its dams but did not report on whether any were breached.
4. Choosing a Sediment Management Option for Dam Removal
This was another popular 2012 magazine article, covering four options considered for managing sediment during removal of a large dam in the western U.S. Sediment management plays a critical role in the choice of a dam removal method, the author says, because sediment trapped behind a dam drastically affects the cost and environmental impact. The method chosen for this particular dam, called the retained sediment approach, involved leaving sediment in place and rerouting the river around the dam site.
5. Alkali-aggregate reactions make Mactaquac hydropower project’s future unclear
This April news story informed readers about how faulty concrete has significantly shortened the intended 100-year lifespan of NB Power’s 672-MW Mactaquac plant, completed in 1968. The concrete in the spillways and generating station is expanding. The plant provides about 20% of the province’s total power, and to deal with the problem could cost as much as US$3 billion. NB Power anticipated performing studies and public consultations about the future of the project in 2014.
6. NB Power hires group to evaluate future of 672-MW Mactaquac hydropower plant
In this follow-on story to the one immediately above, published in October, we reported that NB Power commissioned a US$2.3 million study to determine future options for Mactaquac. NB Power said the generating station will reach the end of its lifespan by 2030, at which point the company must rebuilt the station with a new powerhouse and spillway, maintain the earthen dam and spillway only, or restore the river to its natural state. The study is being coordinated by the Canadian Rivers Institute and is expected to take three years to complete. It will evaluate “key environmental challenges” related to the plant’s future, including river health, fish passage and flow management.
7. DamWatch: New Monitoring Technology for Dam Safety
This March magazine article reports on DamWatch, a new software system designed to monitor and store data related to dam safety. The system was designed to monitor and store data for 2,107 watershed dams (typically an embankment dam with a conduit for discharge of smaller storm flows and a vegetated earthen open spillway to convey large storm flows) in Oklahoma. The Oklahoma Natural Resources Conservation Service funded the project as a national pilot for a web-based information system for watershed dams. A nationwide system was expected to be operational by late spring 2013.
8. A Challenging Gate Repair at Cowlitz Falls
By news standards, this July 2010 magazine article is pretty elderly, but it obviously still holds considerable interest to website visitors. When a low-level sluice gate failed during record flooding at the 70-MW Cowlitz Falls project in Washington, a team of engineers and workers put together a plan to repair and close the gate in a short amount of time. The total project cost for the design, modification and emergency closure was $250,000, plus $850,000 in lost generation revenue.
9. Rockslide damages penstock at 88-MW Montrose plant in Canada
A naturally occurring rockslide damaged a 200- to 300-meter-long section of the penstock that supplies water to the 88-MW Montrose plant in British Columbia, Canada, in December 2012. Montrose is part of the 234-MW Toba Montrose project, which was completed in late 2010. This incident forced the plant off line for several months, and repairs were to be carried out during the winter months when water flows and power generation are lower, owner Alterra Power Corp. said.
10. National Dam Safety Awareness Day commemorates Johnstown disaster
National Dam Safety Awareness Day, declared in 1999 by the Federal Emergency Management Agency, is recognized every May 31 to commemorate the 1889 Johnstown disaster. The failure of South Fork Dam resulted in the deaths of 2,209 people and hundreds of millions of dollars in property and infrastructure damage. This special day provides an opportunity to educate the public about the benefits of dams and risks associated with potential dam incidents and failures.
There you have it, the most-read dams and civil structures stories of 2013 from HydroWorld.com. If you have a “hot topic” you’d like to see us cover, e-mail email@example.com.
Elizabeth Ingram is senior editor of Hydro Review.