Las Vegas would see a number of interstate improvements. The map below shows these various improvements. Solid Blue Lines indicate new free ultimate interstate routes. Dotted lines show additional concept route alignments or alternative routes. Red lines show existing Interstate highways.

Interstate 11 - Metro Las Vegas
Description Originating from Gila Bend, Arizona I-11 travels north into Nevada crossing the new Colorado River Bridge near the Hoover Dam. It will travel south of Boulder City on a planned bypassroute and will be routed to Las Vegasreplacing the existing I-515 designation. from there it will continue nowrthwest on the US-95 (Oran K Gragson Freeway and travel northalong the US-95 alignment toward Reno. North of Las Vegas the route will generally follow US-95 northward through Nevada, Oregon, Idaho, and Washington eventually ending in Spokane.
Purpose and Need This corridor solves several transportation issues. First it provides a connection from Phoenix to Las Vegas, Connects Las Vegas to Reno, and points north. Additionally there is a high volume of truck and commercial traffic along several sections of this corridor.
Interstate 211 - Summerlin Parkay
Description THis applies the I-211 designation to the existing Summerlin Parkway freeway and improves the west interchage at the planned ultimate interstate I-215 (Currently Clark County 215).
Purpose and Need To promote interstate continuity.
Notes Depending on planned growth west of corridor 215 the interstate 211 corridor could be extended west if needed. This would create a spur so a I-111 designation would be preferred in that case.
Interstate 580 Extension - Nevada
Description This Ultimate interstate corridor extension is currently awaiting designation as I-215 pending several interstate improvements along the corridor. Once fully upgraded to full interstate standard the I-215 designation will be applied to the remainder of the corridor. Additionally the beltway could be completed by adding a fourth eastern leg.
Purpose and Need Continuity with the existing interstate system. And to address Las Vegas traffic needs and anticipated growth.