From ENR online - -
"CH2M Hill's Freas says, "The utility community is like any other community, so those that are really at risk …tend to be the leaders." The San Francisco Public Utilities Commission (SFPUC) is one of those out in front. Like southern Florida, San Francisco's wastewater and stormwater infrastructure has been affected by sea-level rise. Over the past four or five years, during high-tide storm events, saltwater has overwhelmed the combined-sewer overflow system and infiltrated the wastewater treatment plants. "We had a very high tide in December 2012, and we had pure saltwater pouring into our system," says Karen Kubick, SFPUC's wastewater enterprise capital program director. "That's a concern because it can really negatively affect the [wastewater treatment] plants" by wasting energy and compromising the biological organisms used for treatment.
SFPUC has identified 27 points where saline bay water is forecast to enter the combined-sewer/waste-water system over the next several years. SFPUC has committed $40 million for a combined-system backflow prevention project, the first phase of retrofits to the system's infrastructure. The project, now under design, is one of the first "climate-justified" projects in the country, says Kubick, meaning that if it were not for climate- change research, the project would not be built.
David Behar, climate program director at SFPUC, adds, "There are very few climate-justified projects that are currently funded and on people's capital plans in part because a lot of people are still catching up in terms of figuring out the vulnerability" of their assets.
Additionally, in the future, all projects SFPUC embarks on will consider climate change, Kubick says. New facilities will be sited to accommodate or adapt to an expected sea-level rise over their lifetime, and officials will evaluate existing infrastructure, she says.
At the other end of the spectrum, extreme drought conditions in the city of Midland, Texas, have caused two of the town's three surface reservoirs to go dry. A third is expected to run dry before the end of the year. In a public-to-public partnership, Midland teamed with the Midland County Fresh Water Supply District No. 1 to address the water-supply shortage. The project—awarded for an undisclosed amount to a joint venture of Overland Park, Kan.-based Black & Veatch and Kansas City-based Garney Construction Inc.—involved drilling a new raw-water well field that has approximately 44 wells and building a 58-mile-long pipeline to convey the water from the well field to the city. The team completed the fast-track design-build project in less than a year. The project, which went on line in May 2013, can deliver 20 million gallons of water a day to Midland.
In California, the Bay Delta Conservation Plan, currently in the planning stages, would provide, if built, a source of water from the Sacramento-San Joaquin Rivers Delta and San Francisco Bay—together known as the California Bay Delta—down to Southern California while striving to protect wildlife and fragile ecosystems. Further, that project is incorporating impacts of climate change related to sea-level rise and snowpack melt into some of its design parameters.
Finding alternative sources of water will become increasingly important as freshwater supplies become more scarce, notes Ben Chou, water policy analyst for the Natural Resources Defense Council."
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