ASCE Los Angeles Section

Ontario, CA

The North Milliken Grade Separation Project (Project) includes a roadway and railroad track grade separation at the Milliken A venue and Union Pacific Railroad (UPRR) Alhambra Line crossing located in the City of Ontario. Currently there are more than 36 freight trains traversing Milliken Avenue averaging 5 minutes each, with estimates for more and longer trains in the future. This vital crossing was ranked 8 of 75 in priority on the California Public Utilities Commission (CPUC) Section 190 Grade Separation Priority Study list. The Primary goal for this project was the ability to separate the train traffic from the vehicle traffic on Milliken A venue with minimal disruption to existing traffic flow and without severing access to any of the surrounding businesses.

During the planning and design stages of this project a variety of challenges were encountered including constructing a costly shoofly track on private properties behind the local industrial businesses utilizing an extensive temporary sheet pile shoring system, and incurring excessive project costs associated with right of way acquisition and temporary construction easements, preserve free traffic flow for both trains and vehicles through and around the project area and to maintain good rapport with everyone impacted by this project.

These challenges made the cost go up so much that it made the feasibility of funding this project in jeopardy. Considering the size, cost, location and importance of the project, the City of Ontario decided to hire a constructability review team to review and evaluate the multiple design options throughout the design period. This approach ended up saving the project millions of dollars. With this review the project was re-designed to use a new proprietary type of MSE walls known as “T- Walls”. With the use of a special double ended T-Wall, the south half of the bridge was constructed first. The north part of the double ended T-Wall acted as a shoring (retaining) wall allowing the tracks to be placed on the fully constructed ramps and over Milliken A venue Bridge thus eliminating the “at grade” crossing 14 months earlier than anticipated.

The time saving was realized because no at grade shoofly was constructed and no right of way acquisition or temporary construction easements were necessary as all of the track work was done within UPRR right of way. This type of construction also allowed for the project to maintain live train and vehicle traffic as Milliken Avenue was only closed during specified weekends. The north half of the structure was then constructed using T-Wall sections while the shoring (retaining) section of the south T-Wall was buried. The final phase of the project was to widen Milliken A venue under the structure to allow for 4 thru lanes northbound and 3 thru lanes south bound, and landscaping under the bridge.

The City of Ontario, San Bernardino Associated Governments (SANBAG) and the San Bernardino County Flood Control District (SBCFCD) all worked together to make this project a success. This project also aided with the construction of a much needed flood control basin for the SBCFCD at the Turner Basin site, which is approximately 3 miles from the Milliken Project.
The City of Ontario coordinated the effort to design the select backfill requirements for the Project’s one and a half mile ramps with the material that was generated from the Turner Basin site. This economical source of nearly 200,000 cubic yards of select backfill allowed for both the Milliken A venue Grade Separation and Turner Basin Projects to be constructed simultaneously while saving more than $2 Million for both agencies.

All Project team members worked diligently to review and approve the change from a structural steel plate girder bridge to a precast box beam bridge resulting in a net savings of $650,000. The original cost estimate for the Project was $63 Million as previously designed. The revised Engineer’s construction estimate when the Project was bid was $48 Million. The lowest responsible bidder was awarded the Project for $27 Million, less than half the original cost. The Project was completed on time and under budget resulting in a taxpayer savings of approximately $36 Million and a $2 Million flood basin.

See project photos in attached document.

The North Milliken Grade Separation Project (Project) includes a roadway and railroad track grade separation at the Milliken A venue and Union Pacific Railroad (UPRR) Alhambra Line crossing located in the City of Ontario. The Primary goal for this project was the ability to separate the train traffic from the vehicle traffic on Milliken A venue with minimal disruption to existing traffic flow and without severing access to any of the surrounding businesses.

The North Milliken Grade Separation Project (Project) includes a roadway and railroad track grade separation at the Milliken A venue and Union Pacific Railroad (UPRR) Alhambra Line crossing located in the City of Ontario. Currently there are more than 36 freight trains traversing Milliken Avenue averaging 5 minutes each, with estimates for more and longer trains in the future. This vital crossing was ranked 8 of 75 in priority on the California Public Utilities Commission (CPUC) Section 190 Grade Separation Priority Study list. The Primary goal for this project was the ability to separate the train traffic from the vehicle traffic on Milliken A venue with minimal disruption to existing traffic flow and without severing access to any of the surrounding businesses.