Analyses / Public Summary / 119 · S 3743 Public Summary

119-S-3743 Journalist Public Summary

119 · S 3743 A bill to direct the Secretary of the Interior to carry out a feasibility study on a selective water withdrawal system at Glen Canyon Dam, and for other purposes.

A short, plain‑language overview of S. 3743 (119th Congress), which would have the Interior Department study whether adding a “selective water withdrawal” system at Glen Canyon Dam is feasible, with the aim of improving hydropower output during cold‑water releases and reducing invasive species entrainment; it sets an 18‑month deadline for the study, uses nonreimbursable federal funds, and does not change the separate post‑2026 Colorado River operating guidelines.

Published
18 Mar 2026
Updated
18 Mar 2026
Tags
Public Summary · U.S. Congress · Colorado River
Unvetted
01 · Section

Headline Summary

A Senate bill would order an 18‑month federal study on adding equipment at Glen Canyon Dam to let operators draw water from different depths, aiming to improve hydropower while reducing invasive species risks—without changing broader post‑2026 Colorado River operations.

02 · Section

What It Does

S. 3743 directs the Interior Department (through the Bureau of Reclamation), in consultation with the Energy Department and Colorado River Storage Project power contractors, to study the feasibility of a “selective water withdrawal” system at Glen Canyon Dam. The study must include hydrologic modeling and focus on optimizing hydropower when releasing cold water while preventing invasive species from being pulled through the dam. If Interior finds an alternative feasible under reclamation law—and the power contractors concur—the Department may proceed with environmental compliance and construction. The bill uses appropriated, nonreimbursable federal funds; Interior must identify funding sources within 90 days of enactment. It explicitly leaves the separate post‑2026 operating guidelines for Lakes Powell and Mead unchanged.

03 · Section

Who’s For It

  • Sponsor: Sen. Mike Lee (R‑UT).
  • Colorado River hydropower customers and grid operators are likely to view a feasibility study favorably because better temperature‑control options can stabilize power generation and potentially lower costs to ratepayers.
  • Some fisheries and park managers may see value in tools that help maintain desired cold‑water releases and reduce entrainment of invasive fish below the dam.
04 · Section

Who’s Against It

  • Fiscal hawks may object to using nonreimbursable federal funds for dam hardware studies and potential construction.
  • Some environmental and river‑restoration advocates could argue this pursues a hardware fix instead of tackling larger water‑use and ecosystem issues on the Colorado River.
  • Stakeholders wary of altering downstream temperature or flow patterns may raise concerns about ecological trade‑offs, cost, or unintended impacts during drought operations.
05 · Section

What’s Next

Status as of March 18, 2026: Introduced January 29, 2026; read twice and referred to the Senate Energy and Natural Resources Committee; the Subcommittee on Water and Power held a hearing on March 17, 2026. Next steps could include a subcommittee markup, full committee vote, and then consideration by the full Senate. If it passes the Senate, the bill would move to the House; if enacted, Interior would have 18 months to complete the study and 90 days to identify funding sources.

06 · Section

Key Facts & Dates

Bill
3743S.
Congress
119th
Introduced
20260129YYYYMMDD
Latest action noted
20260317Subcommittee hearing
Study deadline after enactment
18months
Funding ID window after enactment
90days
07 · Section

What This Bill Doesn’t Do

Discussion