The Purple Line Extension Section 1 Tunnel Boring Machines (TBMs), Elsie and Soyeon, are currently digging under Wilshire Bl. They will construct two parallel tunnels to create a seamless connection from the current Purple Line terminus at Wilshire/Western Station in Koreatown to three new stations located at Wilshire/La Brea, Wilshire/Fairfax and Wilshire/La Cienega.
Elsie and Soyeon are responsible for building 17,845 linear feet of tunnels to create approximately 3.9 miles of new subway. They have completed Reach 1 and are on their way to completing Reaches 2 and 3.
Harriet and Ruth, the Purple Line Extension Section 2 TBMs, will be building the connection between the Wilshire/La Cienega and Wilshire/Rodeo Stations in Beverly Hills and the Century City/Constellation Station. They will build approximately 2.6 miles of new subway and will be creating 13,630 linear feet of tunnels. Harriet and Ruth are expected to start tunneling Winter 2019.
Along the way, TBMs will encounter different soil conditions. The tunnel crown will always be at least 20 feet or more under the subsurface water table.
In terms of geology, tunnels will be bored through two types of geological formations: San Pedro and Fernando.
Tunneling Statistics
Progress is measured in total linear feet traveled.
Section 1 Tunneling
|
Reach |
Linear Feet |
Location |
|---|---|---|
|
1 |
9,570 |
La Brea Bl to Western Av |
|
2 |
4,440 |
La Brea Bl to Fairfax Av |
|
3 |
3,280 |
Fairfax Av to La Cienega Bl |
|
4 |
555 |
La Cienega Bl to tail track west of La Cienega Bl |
Section 2 Tunneling
|
Reach |
Linear Feet |
Location |
|---|---|---|
|
4 |
6,610 |
Reeves Dr to La Cienega Bl |
|
5 |
7,020 |
Constellation Bl to Reeves Dr |