Construction Overview
Caltrain Electrification construction is occurring between the 4th and King Station in San Francisco and Tamien Station in San Jose. Construction activities include locating underground utilities, testing soil conditions, inspecting signal/communication equipment, pruning/removing trees, and installing foundations in preparation for the installation and operation of the Overhead Contact System that will power the new electric trains.
Work will be performed during the day and at night. In order to limit the impact to regular train service, night work will occur between 8 p.m. and 6 a.m. when there are fewer regular service trains.
Construction Map
Click the map below for construction progress along the corridor. Work is organized by four segment areas, with work occurring in segments 2 and 4 followed by work in segments 1 and 3. Current work is indicated by the 
red circles on the map. Last Updated: October 11, 2021.
San Francisco
Brisbane
South S.F.
San Bruno
Millbrae
Burlingame
San Mateo
Belmont
San Carlos
Redwood City
Uninc. San Mateo County
Atherton
Menlo Park
Menlo Park
Palo Alto
Mountain View
Sunnyvale
Santa Clara
Santa Clara
San Jose
Weekly Updates
For the upcoming week, the activities associated with the electrification infrastructure component of the CalMod Program are the following. Sign up for weekly updates here.
For more additional information about construction, please visit our City Specific Resources page.
January 22 to January 28, Caltrain will be working during the night to install foundations. Night work hours will be from 7 p.m. to 6 a.m. We apologize for any inconvenience this may cause and the field team will work as quietly as possible.
Beginning January 24 through 26, 2022, Caltrain will continue foundation installation work in San Francisco that will require a temporary closure of one westbound lane of King Street at 4th Street to vehicle and bicycle traffic. To learn more, please visit our Resources page.
No work During work hours at the 22nd St. station all passengers will board and de-board from the same platforms. Please look for the signs to indicate which platform to use. If you have any questions, feel free to call Caltrain Customer Service at 1.800.660.4287.
No work anticipated this week.
During work hours at the Bayshore station all passengers will board and de-board from the same platforms. Please look for the signs to indicate which platform to use. If you have any questions, feel free to call Caltrain Customer Service at 1.800.660.4287.
No work anticipated this week.
During work hours at the South San Francisco station all passengers will board and de-board from the same platforms. Please look for the signs to indicate which platform to use. If you have any questions, feel free to call Caltrain Customer Service at 1.800.660.4287.
On January 22 to January 28, Caltrain will be working during the night to install poles. Night work hours will be from 7 p.m. to 6 a.m. We apologize for any inconvenience this may cause and the field team will work as quietly as possible.
During work hours at the San Bruno station all passengers will board and de-board from the same platforms. Please look for the signs to indicate which platform to use. If you have any questions, feel free to call Caltrain Customer Service at 1.800.660.4287.
On January 22 to January 28, Caltrain will be working during the night to install poles. Night work hours will be from 7 p.m. to 6 a.m. We apologize for any inconvenience this may cause and the field team will work as quietly as possible.
During work hours at the Millbrae station all passengers will board and de-board from the same platforms. Please look for the signs to indicate which platform to use. If you have any questions, feel free to call Caltrain Customer Service at 1.800.660.4287.
On January 22 to January 28, Caltrain will be working during the night to install poles. Night work hours will be from 7 p.m. to 6 a.m. We apologize for any inconvenience this may cause and the field team will work as quietly as possible.
During work hours at the Burlingame and Broadway stations all passengers will board and de-board from the same platforms. Please look for the signs to indicate which platform to use. If you have any questions, feel free to call Caltrain Customer Service at 1.800.660.4287.
On January 22 to January 28, Caltrain will be working during the night to install poles. Night work hours will be from 7 p.m. to 6 a.m. We apologize for any inconvenience this may cause and the field team will work as quietly as possible.
During work hours at the San Mateo, Hayward Park and Hillsdale stations all passengers will board and de-board from the same platforms. Please look for the signs to indicate which platform to use. If you have any questions, feel free to call Caltrain Customer Service at 1.800.660.4287
On January 22 to January 28, Caltrain will be working during the night to install poles. Night work hours will be from 7 p.m. to 6 a.m. We apologize for any inconvenience this may cause and the field team will work as quietly as possible.
During work hours at the Belmont station all passengers will board and de-board from the same platforms. Please look for the signs to indicate which platform to use. If you have any questions, feel free to call Caltrain Customer Service at 1.800.660.4287
No work anticipated this week.
During work hours at the San Carlos station all passengers will board and de-board from the same platforms. Please look for the signs to indicate which platform to use. If you have any questions, feel free to call Caltrain Customer Service at 1.800.660.4287
No work anticipated this week.
During work hours at the Redwood City station all passengers will board and de-board from the same platforms. Please look for the signs to indicate which platform to use. If you have any questions, feel free to call Caltrain Customer Service at 1.800.660.4287.
No work anticipated this week.
On January 22 to January 28, Caltrain will be working during the day to prune and remove trees along the project route. Day work hours will be from 7 a.m. to 7 p.m. We apologize for any inconvenience this may cause and the field team will work as quietly as possible.
No work anticipated this week.
During work hours at the Menlo Park station all passengers will board and de-board from the same platforms. Please look for the signs to indicate which platform to use. If you have any questions, feel free to call Caltrain Customer Service at 1.800.660.4287.
No work anticipated this week.
During work hours at the Palo Alto and California stations all passengers will board and de-board from the same platforms. Please look for the signs to indicate which platform to use. If you have any questions, feel free to call Caltrain Customer Service at 1.800.660.4287.
On January 22 to January 28, Caltrain will be working during the night to perform bridge barrier installation work. Night work hours will be from 7 p.m. to 6 a.m. We apologize for any inconvenience this may cause and the field team will work as quietly as possible.
Caltrain will be performing bridge barrier installation work in Mountain View that will require the temporary closure of the right eastbound lane of the Whisman Drive at Central Expressway Bridge. Work will take place January 18 through 31 between 8:30 pm and 5:00 am. To learn more, please visit our Resources page.
During work hours at the Mountain View and San Antonio stations all passengers will board and de-board from the same platforms. Please look for the signs to indicate which platform to use. If you have any questions, feel free to call Caltrain Customer Service at 1.800.660.4287.
On January 22 to January 28, Caltrain will be working during the day to prune and remove trees along the project route. Day work hours will be from 7 a.m. to 7 p.m. We apologize for any inconvenience this may cause and the field team will work as quietly as possible.
During work hours at the Sunnyvale and Lawrence stations all passengers will board and de-board from the same platforms. Please look for the signs to indicate which platform to use. If you have any questions, feel free to call Caltrain Customer Service at 1.800.660.4287.
On January 22 to January 28, Caltrain will be working during the night to install equipment on poles. Night work hours will be from 7 p.m. to 6 a.m. We apologize for any inconvenience this may cause and the field team will work as quietly as possible.
During work hours at the Santa Clara station all passengers will board and de-board from the same platforms. Please look for the signs to indicate which platform to use. If you have any questions, feel free to call Caltrain Customer Service at 1.800.660.4287.
On January 22 to January 28, Caltrain will be working during the night to install equipment on poles. Night work hours will be from 7 p.m. to 6 a.m. We apologize for any inconvenience this may cause and the field team will work as quietly as possible.
During work hours at the Diridon, Tamien and College Park stations all passengers will board and de-board from the same platforms. Please look for the signs to indicate which platform to use. If you have any questions, feel free to call Caltrain Customer Service at 1.800.660.4287.
For more information, please call the dedicated outreach line at 650.508.6499; visit the website at www.calmod.org or email calmod@caltrain.com.
Construction Activities
<b>Overhead Catenary System</b><br>Caltrain Electrification includes the installation of the overhead catenary system (OCS) which consists of foundations, poles, and four different types of wires.
<b>Overhead Catenary System</b><br>Caltrain Electrification includes the installation of the overhead catenary system (OCS) which consists of foundations, poles, and four different types of wires.
<b>Potholing</b><br>In order to prepare for the installation of foundations and poles, crews use an industrial vacuum to excavate each foundation location and confirm the condition and location of underground utilities.
<b>Potholing</b><br>In order to prepare for the installation of foundations and poles, crews use an industrial vacuum to excavate each foundation location and confirm the condition and location of underground utilities.
<b>Foundation Installation</b><br>Over 3,000 concrete foundations will be installed along the Caltrain corridor. Crews use an auger drill to dig a hole, place rebar, and then pour concrete to fill the hole. The concrete foundation is left to set for a month before crews can return, remove formwork, and install a pole atop the foundation. Some foundations will be used to support a guy-wire.
<b>Foundation Installation</b><br>Over 3,000 concrete foundations will be installed along the Caltrain corridor. Crews use an auger drill to dig a hole, place rebar, and then pour concrete to fill the hole. The concrete foundation is left to set for a month before crews can return, remove formwork, and install a pole atop the foundation. Some foundations will be used to support a guy-wire.
<b>Pole Installation</b><br>After a foundation has been set, crews return to install the poles and catenary supports which hold the overhead wires. Poles are between 30-50 feet high and are installed using cranes and off-track equipment. Depending on site conditions and system requirements, poles can be placed outside or in between the set of railroad tracks. In most locations, poles are placed approximately 180′ apart.
<b>Pole Installation</b><br>After a foundation has been set, crews return to install the poles and catenary supports which hold the overhead wires. Poles are between 30-50 feet high and are installed using cranes and off-track equipment. Depending on site conditions and system requirements, poles can be placed outside or in between the set of railroad tracks. In most locations, poles are placed approximately 180′ apart.
<b>Wire Installation</b><br>Once there is a continuous set of poles in an area, crews will string the wires needed for the system. These wires provide 25kV overhead power to the new electric trains.
<b>Wire Installation</b><br>Once there is a continuous set of poles in an area, crews will string the wires needed for the system. These wires provide 25kV overhead power to the new electric trains.
<b>Tree Pruning/Removal</b><br>An electrical safety zone (ESZ) of up to 24 feet from the tracks has been established in order to provide the required clearance for the overhead catenary system. Trees within the ESZ must be pruned or removed prior to construction. Caltrain will replace all trees removed or pruned more than 25%.
<b>Tree Pruning/Removal</b><br>An electrical safety zone (ESZ) of up to 24 feet from the tracks has been established in order to provide the required clearance for the overhead catenary system. Trees within the ESZ must be pruned or removed prior to construction. Caltrain will replace all trees removed or pruned more than 25%.
<b>Traction Power and Substation Info</b><br>Traction power substations supply and regulate the power to the electrified system. Ten of these substations will be installed between San Francisco and San Jose. For more information on the different types of substations and their locations, visit the Traction Power Substation Page.
<b>Traction Power and Substation Info</b><br>Traction power substations supply and regulate the power to the electrified system. Ten of these substations will be installed between San Francisco and San Jose. For more information on the different types of substations and their locations, visit the Traction Power Substation Page.
<b>Bridge Barriers</b><br>All bridges that cross over Caltrain tracks will require the installation of a protective barrier and screen to ensure the safety of both our trains and the public.
<b>Bridge Barriers</b><br>All bridges that cross over Caltrain tracks will require the installation of a protective barrier and screen to ensure the safety of both our trains and the public.
<b>Insulated Joint Installation</b><br>Before Caltrain can convert to an electrified system, insulated joints must be installed in order for the train locations to be detected along the corridor by the signal system. Crews will remove sections of rail and install prefabricated insulated joints. The prefabricated joints are then welded and ground to form a continuous rail along the corridor.
<b>Insulated Joint Installation</b><br>Before Caltrain can convert to an electrified system, insulated joints must be installed in order for the train locations to be detected along the corridor by the signal system. Crews will remove sections of rail and install prefabricated insulated joints. The prefabricated joints are then welded and ground to form a continuous rail along the corridor.
<b>Duct Bank Installation</b><br>The new electrified system will require the installation of additional underground electrical, signal, and communications cabling known as duct banks.
<b>Duct Bank Installation</b><br>The new electrified system will require the installation of additional underground electrical, signal, and communications cabling known as duct banks.
