Capistrano Beach Credit: RailPAC

Addressing climate change and reducing greenhouse gas (GHG) emissions is not achieved by one big initiative, but is the combined result of many small initiatives – changing to a LED lightbulb, recycling, combining errands, setting a thermostat to a more efficient level, additional insulation, etc.  One of the significant initiatives is to undertake rail line improvements, enabling service levels that shift travelers from the automobile to the energy efficient rail mode.  The Serra Siding Extension and bridge replacement is an example of these projects.

The goal of the Rail Passenger Association of California (RailPAC) is to advocate for rail improvements that, when combined, dramatically reduce GHG emissions and mitigate climate change, while also forestalling traffic gridlock.  Without shifting significant levels of travel from road vehicles to the more efficient rail mode, there can be no credible strategy to sufficiently reduce GHG emissions. 

The overall environmental attributes of the rail mode manifest themselves in several key areas.

Energy Efficiency

Rail passenger service is greatly more fuel efficient than travel by automobile; and thus can substantially lower greenhouse gas emissions.  Intercity (Amtrak Pacific Surfliner) and commuter trains (Metrolink), per person-mile traveled, use less than half the energy of automobiles and even less compared to light trucks

Locomotive Pollution

The passenger locomotives recently introduced on trains through Capistrano Beach, Metrolink Progress F125 and Amtrak Siemens Chargers, meet EPA Tier 4 locomotive requirements. These Tier 4 compliant locomotives produce 85% less pollutants (particulates, nitrous oxide, hydrocarbons and carbon monoxide) than the locomotives they replaced.  Because these locomotives are more fuel efficient, they also produce less greenhouse gases.  New freight locomotives must also meet this same standard.  Also now underway by Metrolink is the replacement of diesel fuel with renewable fuel made from recycled fats and vegetable oil.  This “green” fuel will further reduce local particulates, nitrous oxide and hydrocarbons while further reducing greenhouse gas emissions.

The next step, with the first units on order by Amtrak, will be the addition of battery cab cars using battery power from regenerative braking to supplement the locomotive.  This will turn the train power system into a hybrid, increasing fuel efficiency and reducing GHG emissions by another 15 to 20%.

Finally, an extended Serra Siding, linked together with the existing siding, enables “running meets”, allowing trains in opposing directions to pass without stopping.  Since the through-running trains do not have to stop, this new siding would eliminate the current idling and acceleration from a stop as a result of a meet at the current short siding. As a result, “running meets” will reduce the amount of local pollution and noise in Dana Point.

Noise impacts

Recently RailPAC conducted noise readings on a sidewalk in front of the hotels/timeshare condos along Pacific Coast Highway on a warm Sunday afternoon. An Amtrak Pacific Surfliner with a new diesel locomotive, maxed out at about 78 dBm and was audibly ‘somewhat loud’ for about 15 seconds while passing by. This compares to typical loud sports cars, which maxed out at around 90 dBm, and sometimes over 100 dBm.   Motorcycles measured were often greater than 80 dBm, and sometimes higher than 90 dBm.   On a typical warm weekend afternoon, exceptionally loud motorcycles and cars went by at a rate of 10 to 20 vehicles per hour, compared to one to two trains per hour.   Baseline (continuous) traffic noise of typical passing vehicles on Pacific Coast Highway hovered between 70 and 85 dBm, a similar sound level as the passing trains and often higher.

Motorcycle on Pacific Coast Highway, loudness measured at 86 dBm. RailPAC measurements, April 24, 2022

Land Use

The rail mode uses much less land than a freeway.  A two-track rail line can carry as many travelers as a 16-lane freeway.  With limited impervious surface required for transportation, it also reduces the degradation of aquatic ecosystems.  So, what is the future for southern Orange County?


A sixteen-lane I-5 plus access roads through Dana Point and San Clemente with the loss of many businesses and homes with a footprint of about 350 feet? Google Earth May 24, 2022

Or this?

A two track rail line with a generally permeable surface on an existing right-of-way with a footprint of about 40 feet? Google Earth May 24, 2022

The Serra Siding Extension and Bridge Replacement project is a straightforward construction of a new siding and bridge on an existing right of way that will not displace any homes, businesses or natural features.  Constructing the Serra Siding Extension and Bridge Replacement Project is an investment in a vital piece of public infrastructure; shifting passengers from highway to rail, that will generate benefits and reduce greenhouse gas emissions for many decades.

Finally, the alternative to not improving the reliability and capacity of the LOSSAN rail corridor (the No-Build Alternative), is in reality a counter-productive option.  No-Build instead will result in increasing pressure in coming years to expand I-5 or to connect the Orange County Toll road system to I-5 south of San Clemente.   Either of these outcomes could displace homes and businesses and would result in an increase in noise, toxic pollutants and GHG emissions. For these reasons, I favor approval of construction as of this Serra Siding Extension project

Robert V. Frampton is a Board Member of the Rail Passenger Association of California and Nevada, a non-profit passenger rail advocacy group. Robert recently retired after 40 years as a spacecraft engineer with an Orange County aerospace company, and is a

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