A controversial plan to build a 45-mile-long tunnel to divert water from northern California to the arid south has revived with release of a draft environmental impact report by the California Dept. of Water Resources (DWR).

3,000页的分析概述了拟议的多种选择Delta Conveyance Project. If built, it would take water from the Sacramento River and move it beneath the Sacramento-San Joaquin River Delta to reach the state’s main north-south water supply network. Optimistic scenarios estimate construction getting underway no earlier than 2028 and taking a decade to complete.

DWR董事Karla Nemeth在一份声明中说：“三分之二的加利福尼亚人依靠国家水项目或部分供水。”“对这种基础设施进行现代化，对于适应包括更频繁的干旱和洪水以及更大的水不稳定的未来至关重要。”

当前项目was launched in 2019by state Gov. Gavin Newsom when he scrapped a previous plan featuring a twin-tunnel solution for one with a single tunnel. The effort is aimed at balancing the state’s water supply resources with ever-growing demand amid multiple climate-related uncertainties. Conservation groupshave opposed the pipeline由于可能产生的环境影响。

2020年的估计值使单人隧道系统的成本为160亿美元，尽管该计划的预计成本不在报告中。18luck.cubState-issued bonds for what is expected to be at least a ten-year-long construction effort would be funded by the non-profit State Water Contractors, a 27-member association of local public water agencies that purchase water from the DWR’s 700-mile water storage and delivery system that supplies water to 27 million California residents.

SWC总经理詹妮弗·皮埃尔（Jennifer Pierre）在一份声明中说：“清楚地表明，该项目已被缩减，精致和重新设计，以避免和减少当地影响并解决环境问题。”皮埃尔还称三角洲运输项目为“正确的时间”，以使该州现有的供水基础设施现代化。

当前的计划要求建造一条能够从萨克拉曼多河（Sacramento River）向下45英里的北部北部北部北部北部北部北部北部北部水的水延伸至最高6,000立方英尺（CFS）的管道，以与新的泵站/水式渡槽综合体连接。水将被沉积在连接到加利福尼亚渡槽的伯大尼水库中。

该报告审查了八个对齐替代方案草案，指出伯大尼的一致性“将提供与其他6,000 cfs替代方案相同的气候弹性，地震弹性和供水可靠性”，但环境影响较少或大幅减少。

并非每个人都同意。最初在1960年代被认为是国家供水系统的一部分，萨克拉曼多河三角洲周围的供水概念因其成本，建筑影响和长期环境后果而受到批评，尤其是通过减少淡水流过的生态影响河口。

Information released by DWR as part of the draft report acknowledges that such changes to the delta “have the potential” to affect migration and spawning habitat of several salmon species. Up to 3,500 acres of wetlands would be restored to offset the environmental damage.

气候变化的加速为辩论增加了另一个维度。DWR声称，三角洲运输项目将帮助加利福尼亚的供水系统使用者利用重大风暴和其他极端天气事件的频率增加。如果该项目在2021年10月和12月的大风暴期间运营，该机构声称它本可以捕获并移动了约236,000英亩英尺的水，足以每年提供250万人。

Opponents counter that a more likely scenario are protracted droughts, such as the current three-year-old dry spell that has drastically curbed state water allocations.

“Climate change continues to impact the state’s hydrology, and there is no certainty as to the amount of water that will be available for the project when it’s completed,” Sierra Club California Director Brandon Dawson said in a statement. Instead, he asserts that the state would be better served by focusing on sustainable water management efforts—conservation, efficiency, recycling and stormwater capture—that are environmentally beneficial and a better option for building regional resilience.

另一个批评是潜在的影响，即萨克拉曼多河三角洲将对现有农业客户产生的大量水转移。

Although DWR insists that the Delta Conveyance Project is not proposing to increase the total quantity of water permitted for diversion under its existing water rights, three Sacramento-area congressional representatives recently introduced legislation that would prevent the U.S. Army Corps of Engineers from issuing a Clean Water Act permit for the project.