The planning behind the construction

From ODOT-

If you pass by the project site regularly, you’ve seen the two graceful bridges take shape across the Willamette River. What you don’t see is the coordination that makes it possible.

Communication is critical in such a dynamic project. Every Wednesday, Hamilton Construction Manager Con O’Connor and I meet with the superintendents, safety manager, project engineers and the traffic control manager. At this weekly meeting, the team orchestrates upcoming tasks, identifies potential issues and solves problems. Whatever the issue – coordinating timing of material deliveries, ensuring ample manpower for tying rebar grids, or evaluating erosion-control measures, for example – a cohesive, coordinated planning team makes sure it all gets done.

The primary outcome of each Wednesday’s meeting is a projected three-week schedule that we review each Thursday in our weekly construction meeting with representatives from the main construction partners, Hamilton and Slayden, as well as members of our engineering, inspection, safety and public involvement teams. Here we make sure everyone’s on the same page about upcoming activities, whether related to demolition, bridge work or roadway work. Then we are able to identify where extra efforts are needed to ensure staffing is available and the public is kept safe and informed.

In a construction project, tasks are bound to change due to scheduling conflicts or uncontrollable factors such as the weather. As a team, the Willamette River Bridge staff uses the most current information available and communicates often with all involved parties to ensure that everything runs smoothly as possible.

Close Coordination with Utilities is Required

From ODOT-  The need for close coordination with the local utilities is not often noticed or discussed on major construction projects, yet it is important to prevent impacts to service to local residents.  On the Willamette River Bridge project, water, sewer, natural gas, electrical and major fiber optics cables are all found in the construction zone.  Crews need to relocate many lines and carefully mark and avoid others as the work proceeds.

The pictures above show the future path of the new multi-use viaduct path on the north side of Franklin Boulevard before and after crews removed utility poles in preparation for construction.

Removal of the guardrails will provide an open area for large equipment to drill shafts and begin path construction.

As work begins you can clearly see why the utility poles and guardrail were removed.

A great deal of planning is required before any poles, lines or pipes are moved.  Our contractors meet with the appropriate service providers to outline the impacts, options and timing for any changes.  Close coordination ensures that the utility can schedule its work to occur before our construction activities begin.  ODOT appreciates this close cooperation as we work together to complete this project.

Building cofferdams is the first step in building the new northbound bridge

From ODOT -
With the temporary bridge removed, construction on the new northbound Willamette River Bridge drilled shafts will begin early in the new year. We plan to open this bridge to traffic by fall 2013. Before then, a lot of work needs to be done.
A critical first step is constructing cofferdams. These temporary enclosures keep water and soil out of the work area while we build new bridge footings and shafts in the river and on each bank.
To build our cofferdams, crews drive sheet piles deep down to the bedrock to establish a enclosure. They then excavate soil from inside the enclosure. Water may be needed to be pumped out to create a dry and safe work space.
When the cofferdams are finished, we will use large drilling equipment to bore holes deep in the ground so workers can install steel reinforcement and pour concrete shafts to provide support for the bridge columns.
We’ll have more photos and details on building the new bridge as construction work continues.
This photo shows one of the cofferdams from the southbound bridge.

Temporary fish ladder to help with migration

From ODOT-

In cooperation with the Oregon Department of Fish and Wildlife, our contractor installed a temporary fish ladder near the new Willamette River Bridge.

You may wonder what a fish ladder has to do with the new bridge. Let me explain.

A protected wetland fed by waters from Augusta Creek, Glenwood Slough and other local streams sits on the south bank of the Willamette River near the bridge. Currently, water from the wetland flows through a pipe under Franklin Boulevard to the river. Unfortunately, juvenile fish can’t get safely into the river because the pipe outlet is too high above the river. This also prevents mature fish from returning upstream to spawn.

Recently, biologists identified cutthroat trout upstream from the pipe outlet. We have built a fish ladder—a series of steps that helps fish swim around barriers—as a temporary solution to support the local fish population.

Our bridge project includes restoring the wetlands and stream system on the south bank of the Willamette River to enhance the natural setting and support fish and wildlife habitat. When the bridges are complete, we will restore the streams in the project area, remove culverts, create spawning ponds and reconstruct a historic stream channel outlet to allow for fish passage without needing a fish ladder.

Until then, the temporary fish ladder will allow cutthroat trout living in the waterways on the south bank of the Willamette River to move freely.

Preparing for traffic to cross the new bridge

From ODOT - When the new southbound Interstate 5 Willamette River Bridge opens later this summer, it will temporarily carry all I-5 traffic until the new northbound bridge is completed.

In addition to completing the bridge, our focus is also now on the related improvements needed before traffic is switched over.

The original bridge had two southbound traffic lanes, with narrow shoulders that did not meet today’s safety standards. The new southbound bridge will accommodate up to three traffic lanes and wider shoulders in its final configuration, with two lanes in each direction during construction of the new northbound bridge.

To connect the existing I-5 travel lanes with the new bridge, the lanes must be widened and the shoulders rebuilt. Then, new stripes must be added to both the lanes and shoulders to temporarily direct northbound and southbound traffic across the southbound bridge.

Work on the lanes north of the Willamette River Bridge is nearly complete. Contractors used reinforced concrete here for the travel lanes rather than asphalt, because concrete is more durable. Asphalt paving will be placed on the shoulders, finished with shoulder aggregate on the outside edges.

Other lane work remains before the new bridge opens to traffic. The lanes connecting the main span to I-5 south of Franklin Boulevard will also be widened and repaved. Rebuilding the traffic lanes on the north and south ends of the bridge is one of the final steps before opening.

Post-tensioning the bridge

From ODOT- Driving by the Willamette River Bridge, you might have seen the contractor building the bridge’s falsework and pouring the concrete for the new bridge. Other activities that are equally critical to completion of the bridge can’t be easily seen.

One of the least seen and least understood activities is post-tensioning of beams and decks that make a bridge stronger than its concrete alone.

Post-tensioning allows the bridge to use longer spans with resulting in fewer support columns. Once post-tensioned, the bridge has the strength to meet the long-term demands of heavy traffic and to better resist an earthquake.

How do we post-tension the bridge? Crews place galvanized steel ducts and rebar in stemwall forms before placing the concrete. After the concrete cures, strands of steel cable (tendons) are anchored on one end of the deck and pulled through the ducts to the opposite side. Large hydraulic jacks attached to the free end stress the cables by pulling them to predetermined forces. Once tensioned, the cables are held in place with anchoring devices. The ducts are then filled with grout to prevent deterioration of the cable during the life of the bridge.

To understand the principles of post-tensioning, imagine a series of wooden blocks with holes drilled in them and a rubber band threaded through the holes. Fasten one end while you hold the other, letting the blocks sag. Now twist the rubber band, tightening the blocks together. When the rubber band is twisted and secured on both ends the blocks remain tight and strong.

On the new southbound Willamette River Bridge, one bridge section north and two bridge sections south of the river are post-tensioned. The deck supported by the two arches over the river is not a post-tensioned span. Instead, they are supported by the arches .

Protecting the Environment

From ODOT - The construction area for the Willamette River Bridge project has multiple environmentally and historically sensitive areas, including the Whilamut Natural Area, Mill Race Ruins, the river itself and its banks. We have taken many measures to protect these areas. Before construction, an inventory of the site documented wetlands, plant and animal species, and areas of historical importance. Fencing and markings have been placed identifying areas to be left undisturbed. During the design phase, bridge piers and other project features were located to avoid impacts as much as practical. Sometimes it was impossible to avoid impacting the protected resources. In these cases, we inventoried items carefully and submitted plans detailing the impacts and strategy for restoration and mitigation which were then approved by local, state and federal regulators before construction began. Environmental monitors conduct inspections to verify that we are meeting the permit requirements and identify any future needs. I am happy to report that we continue to receive positive comments and reviews. Once construction is complete, we will provide new vegetation and habitat, and improve the surrounding areas. Balancing the project need to protect and enhance environmentally and historically sensitive areas during construction requires a strong partnership between the community, ODOT, other State and Federal Agencies, local jurisdictions, and our contractors. We have a path forward. I believe when we are through we will be leaving the area better than we found it.

From ODOT- I imagine that those who live in the Laurel Hill Valley Neighborhood appreciate that our sound wall construction is nearly complete.

Some of you may have noticed that the side facing the neighborhood is enhanced with sculptured concrete representing local geologic forms. Vegetation will be planted later in the areas not covered by this architectural treatment.

The sculpted concrete design was chosen by the Laurel Hill Valley Neighborhood last year. Throughout the input process, it was explained that the sculpted design elements would be used as accents at intermittent points, instead of along the entire wall.

The amount of wall that would ultimately be covered by the sculpted concrete design was determined as the overall project budget was refined. As stewards of the public funds, it was important for us to make a fiscally responsible decision. That is why we placed the design treatment on the most highly visible areas of the new sound wall that will not be covered by vegetation. Information provided to the public included renderings of this design that evolved over time as we learned more about the resources available to us.

The patience of the nearby residents with the noise and disruptions during construction made finishing the job easier. This wall is designed to reduce the overall noise levels we expect from projected increases in traffic on I-5 over the next 20 years.

All that remains is straw mulching the soil for the winter and installing plants that will eventually grow onto the sound wall and cover the slopes of the retaining wall.

Over time, the growing vegetation will blend with the sculptured elements to create a look that I think will nicely complement the wall.

(Picture of the wall today and rendering of the wall as it will look once vegetation grows in.)

Arch Ribs photo story part 3 of 4

From ODOT-
This is part three of our series on the creation of the deck arches that will support the new Willamette River Bridge, and will be beautiful, graceful structures in their own right.

First, we saw how the foundations are built to provide support for the arches. Then, we learned how the arches will connect, and saw the initial formation of the arch frames. This week, we will see how wooden frames and concrete pours shape the columns and arch frams.

In the foreground of this picture are the vertical support spandrels, which were built using the same method as the arch ribes. Based on the rebar-cage frame, crews built wooden forms to define the shape of the columns, filled them with poured concrete in sections and once the concrete is cured, removed the forms to reveal the finished columns.

On top of the steel falsework support frame, crews built a wooden frame to provide a safe platform for the workers and a steady foundation for the massive rebar cages that form the backbone of the arch ribs.

Rebar cages provide support for the concrete, which is poured in sections. The strength of the steel physically ties each section together, making a single, continueous arch out of individually constructed segments. The reinforing steel used on the Willamette River Bridge is the largest diametere available and weighs about 13 pounds per foot. With such a heavy frame, once the arch ribs are poured they will tip the scales at more than 11 million pounds.

In this photo, ironworkers prepare the rebar cages for the wooden forms that surround them and give shape to the poured concrete arch sections.

Next: framing and pouring the arch ribs.

The Rain is Here

From ODOT-
Hi, Karl Wieseke here from ODOT’s Springfield area office.

As ODOT’s construction project manager on WRB, I see firsthand how the weather affects our construction activities.

The rainy fall and winter months present new challenges to ODOT’s commitment to minimizing impacts to the environment by ongoing construction activities.

Over the past several weeks, ODOT and our contractor, Hamilton Construction and their subcontractors, have prepared the work site to minimize the impacts of rain and to keep construction on schedule and within permit requirements.

· We have seeded bare slopes and open spaces, or covered them with straw to absorb and better control runoff.

· Hamilton Construction crews inspected the work bridge and made necessary adjustments to ensure that it captures and treats all the runoff before it reaches the Willamette River.

· We have cleaned out drift logs stuck around and under the work bridge to avoid potential problems from rising river levels brought on by winter rains.

· We have also checked equipment for appropriate protection to capture any possible oil or lubricant leaks mixing with rainwater.

Together, ODOT and Hamilton Construction are determined that when the bridge work is done, the work area, riverbanks and adjacent parklands will be in better condition than before we started work.

Tree wall shields park users of freeway noise

From ODOT-

Original plans for the Willamette River Bridge included removal of existing trees west of Interstate 5 and north of the bridge. Early on, local community stakeholders identified the importance of preserving these trees, which shield park users from the noise of the freeway.

We took the stakeholder's interest seriously. The best solution turned out to be a tree wall along the west side of the southbound I-5 lanes just before the bridge. The wall preserves the trees and provides an edge for the widened southbound lanes without increasing the width of the embankment impacting the trees.

For more information on additional environmental measures we're taking with the I-5 Willamette River Bridge, check out this article from HubDOT, written by ODOT environmental program manager Geoff Crook: Bringing new life to the Willamette River Bridge.

Below is a picture of the now completed wall being constructed.

Saving time and money

From ODOT-

The Willamette River Bridge project is ODOT's largest bridge replacement project to date. We work closely with our contractor to find opportunities to save time and money, while constructing a bridge designed to last 100 years.

Recently, we agreed to purchase steel ahead of schedule to start building the second work bridge a year earlier than originally planned. This allows us to complete some work before this year's in-water work windows ends. For this project working in the river is restricted to windows of time between July and October and the month of April in order to protect endangered and sensitive species in the Willamette River.

Early completion of the work bridge means the contractor can dismantle the detour bridge and do other preparatory work on the northbound Interstate 5 bridge at least six months earlier than originally expected. Saving time helps to save money.

~Jyll

Pouring a column

From ODOT- Pictures from the project.

Pouring a column.

Base of an arch.

The arches are taking shape!

From ODOT-

One of the best parts of a major bridge project is watching the construction team work its magic as a structure takes form. Such is the case on the new Willamette River Bridge. As the pictures below show, the outline of the bridge arches is now visible through falsework built to form the arches. Construction of the falsework requires close attention to detail, ensuring appropriate alignment, and safety for the new bridge. The construction team is doing great work as demonstrated by the progress being made. Take a look the next time you're on the Knickerbocker Bridge and start to visualize the gracefulness of the new bridge.

Boating and floating safely around the bridge project

From ODOT-
The hot weather has arrived!! Earlier today I started seeing people floating down the Willamette River to cool off.

I have floated and canoed the Willamette River in years past as I’m sure many of you have as well. You are accustomed to navigating the Willamette River near the I-5 bridge but what you may not know is that the construction has limited the channel you can safely use in the construction area. The Willamette River Bridge project was designed and is being constructed to keep a river channel open throughout construction.

Our contractor built a workbridge over the Willamette to protect the river from construction debris and to provide a work platform. The pilings to support the bridge have restricted the river to one channel through the construction zone. Always stay to the north side of the river, avoiding the channel near the south bank. Signs posted at ramps and in the river will direct you to the safest channel. For your safety, please obey the signs.

Enjoy the wonderful days of summer, use the river safely and check out our project as you go by.

~Jyll

Web cast and PSA launched

Summer seems to have finally arrived! The timing is great as we have just launched our second Web cast showing you the construction work that is underway and what to expect this year. After viewing the Web cast, as you walk, run or bike through the Whilamut Natural Area, you will have a better sense of the activity you are seeing.

Please also remember to be careful on the path detours and obey the flaggers. We’ve created a Public Service Announcement to alert path users of the importance of obeying flaggers. I encourage you to share this with others who enjoy the paths.

From ODOT-
I don’t know about you but I’m excited to see the sun is out and the temperatures are starting to climb. For many people, me included, that means getting outside more to enjoy the parks and wilderness in Oregon.

As you are probably aware, the Knickerbocker Bridge provides a great vantage point of the construction of the new Willamette River Bridge. If you are like me, you are curious to know more about what the construction crews are doing. With those two items in mind, we installed two informational signs where the bridge is wider for the benches. These signs will tell you a bit about what construction is currently occurring. I hope you will find the new signs helpful.

~Jyll

Congratulations to Hamilton Construction for reaching a safety milestone!

From ODOT- Safety is a major focus for all of us at ODOT and our contractors. On our Willamette River Bridge project, Hamilton Construction just celebrated a significant safety milestone with more than 50,000 person-hours worked without a significant injury or accident. For a project expected to take over 400,000 person-hours, current experience says a lot about the projects focus on safety.

Hamilton celebrated with a catered barbecue lunch for all its employees in Springfield’s Island Park. They also provide employees with gift cards. In addition, Hamilton makes a gift to a local non-profit organization when its crews reach safety milestones.

Hamilton presented a $2,500 check to Northwest Youth Corps which is a local non-profit located near the project in the Laurel Hill Valley neighborhood of Eugene. Northwest Youth Corps operates an accredited, alternative high school. It also employs over 1,000 young people, aged 16 to 19, performing outdoor work such as construction and maintenance of hiking trails, bridges, retaining walls, and campgrounds.

From my vantage point, Hamilton demonstrates the quality of company and the project it is managing by its willingness to take the time to recognize employees for their important role in creating a safe work environment and to make a contribution to Northwest Youth Corps.

Please join me in congratulating Hamilton and its employees for their focus on safety and giving back to our community.

~Jyll Smith, Public Affairs for ODOT

Everybody likes watching big things being built.

From ODOT-
Now’s a perfect time to go see the construction of the new I-5 Willamette River Bridge. A great spot to watch the work is from the Knickerbocker pedestrian and bike bridge in Alton Baker Park.

Right now, installation of the bridge arch “falsework” is starting on the north bank of the Willamette River. Falsework is the temporary steel and wooden structures used to form the bridge arches. After the falsework is completely framed, steel reinforcing bars—called rebar—will be inserted and tied together to strengthen the arches before workers begin pouring concrete to form them.

Contractors will pump high-strength concrete into the bridge falsework from large trucks. Later, once the concrete hardens, the falsework will be removed, revealing the new bridge arches for the first time. The falsework for the first set of arches is scheduled to be removed around August.

The falsework is visible from several vantage points, but the Knickerbocker Bridge provides the best vantage point. There you have a perfect view of the construction work on the new Willamette River Bridge. You can return often to watch how construction goes and see the arches take form. Binoculars can give you a close-up view of the work.

Enjoy your next visit.

~Dick Upton