TunnelsView Photo Gallery Adjustable Tunnel Sizes Available Standard Tunnel Sizes KCP Tunnel: Pictures and Description MOD-U-KAST Tunnel: Vault System 6′ x 12′ Transverse Drainage Interceptor NYSDOT: 18″ Wide x 30″ Deep I.D. Tunnel T1: 28″ Wide x 25.5″ Tall I.D. Related Products Box Culvert Bridge: Arch Culvert Bridge: 3 Sided Rigid Frame