At $15. 7 billion, it would run two giant tunnels each four stories high, for 35 miles under the. may 16, 2024 · the new estimate for the delta tunnel project — which would transform the massive water system that sends northern california water south to farms and cities —. may 17, 2024 · sacramento, calif. (ap) — california gov. Gavin newsom’s administration said thursday it will now cost more than $20 billion to build a giant tunnel. dec 8, 2023 · sacramento, calif.
