PROJECT PROFILE: Florida Pool Deck Uses Geofoam to Reduce Weight

Florida Pool Deck  |  Tallahassee, FL  |  View Project Profile (pdf)

Known primarily for its use as a soil stabilizer in transportation projects, EPS geofoam is being viewed by engineers and contractors as the material of choice for a multitude of other commercial and residential applications.

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Florida pool deck, geofoam installation

Contractors use geofoam to simplify construction of swimming pools in residential, commercial and institutional uses, including hotels, schools and community centers.  Project teams can order the blocks pre-but to precise dimensions or can easily cut them to size and shape on site.  This simplifies the concrete forming process, and greatly reduces weight for construction of rooftop pools or sites with poor load-bearing soils.  Once crews form the pool basin and decks with geofoam, they can apply shotcrete directly to the foam.

In this Florida project, geofoam was used to lighten up the load over the upper elevations building given the pool is on the 2nd floor of this five-store building.  Pool decks are installed on both the East and West buildings on the campus.

Given its low weight, EPS geofoam is well suited as a structural void fill in concrete forming operations.  Crews can easily fabricate virtually any shape or sloe, and the material eliminates separate concrete pours for vertical wall sections and topping slabs.  Applications include bridge column formwork, stadium seating in auditoriums and sports arenas, stairways, podiums, loading docks, and rooftop pool decks.  EPS geofoam can be manufactured into custom-cut blocks in various shapes and sizes to enable contractors to quickly build up these and similar features.

Florida pool deck, geofoam installation

Florida pool deck, geofoam installation

Florida pool deck, geofoam installation

Florida pool deck, geofoam installation

Florida pool deck, geofoam installation

Florida pool deck, geofoam installation

Florida pool deck, geofoam installation

Florida pool deck, geofoam installation

 

 

 

A Park with Soil?

Originally published in Site Prep Magazine, September 2014 (digital edition) (pdf)

Lightweight geofoam enables earthworks for new park located atop Chicago parking garage.

Throughout the summer, Chicago residents and visitors saw what looked like acres of piled snow at a construction site bordering Lake Michigan, despite the city’s typical sweltering June and July temperatures..

The “snow” was actually large, white blocks of expanded polystyrene (EPS) geofoam that contractors were installing to form berms and landscaped contours for the new Maggie Daley Park.

Site Prep Challenges

The Chicago Park District decided to develop a 28-acre site adjacent to the city’s renowned Millennium and Grant parks as a “world-class public landscape at a keystone location” to meet the “evolving open space needs of downtown Chicago.”  The Maggie Daley Park, scheduled for final planting in spring 2015, occupies the former Daley Bicentennial Plaza.  The site was a rail yard and surface parking lot for cars until the early 1950s, at which time the city moved the parking spaces underground.

The "snow" on Chicago's famed waterfront in the heat of summer is actually EPS geofoam, being used to construct Maggie Daley Park atop a parking garage that cannot hold heavy soil.

The “snow” on Chicago’s famed waterfront in the heat of summer is actually EPS geofoam, being used to construct Maggie Daley Park atop a parking garage that cannot hold heavy soil.

Therin lies one of the key site preparation challenges for Maggie Daley Park, which will be located on top of the 3,700-car East Monroe Street

Being built at the foot of Chicago, Maggie Daley Park is being constructed using EPS geofoam that will allow the parking garage below to remain in place.

Being built at the foot of Chicago, Maggie Daley Park is being constructed using EPS geofoam that will allow the parking garage below to remain in place.

Parking Garage.  The park’s landscape architects, Michael Van Valkenburgh Associates of Brooklyn, N.Y., envisioned extensive earthworks, which they described as “curvilinear, topographically dramatic and relentlessly heterogeneous.”  Contractors typically would use soil to form such landscape contours, but that was not feasible for this project because the upper slabs of the sprawling, decades-old parking garage were not designed to accommodate that much weight.

Instead, crews with Chicago-based Walsh Construction used EPS geofoam as an ultra-lightweight yet durable fill to form the park’s hills and valleys.  Geofoam is approximately 100 times lighter than soil (0.7-2.85 lbs./cu.ft. for geofoam compared to 110-120 lbs./cu.ft. for soil), so it enabled the Maggie Daley Park designers to create a visually interesting landscape and still keep the garage in place.  Walsh installed 65,000 cu. yes. of geofoam, along with some geofoam that had been previously installed in Daley Bicentennial Plaza.

“It allows you the freedom to be creative,” landscape architect Peter Schaudt, whose company Hoerr Schaudt Landscape Architects has used goefoam in other Chicago projects, commented in a recent Chicago Sun-Times article.

What Makes Geofoam Special?

Despite its low weight, EPS geofoam is strong enough to support heavy loads, such as those imposed by jet aircraft and locomotives, as demonstrated by its successful use as a sub grade for runways, taxiways and rail beds.  Following are the material’s key physical characteristics.

Weight:  In addition to weighing far less than soil, EPS geofoam is much lighter than other lightweight fills, as per the chart below.

site prep_maggie daley3Compressive Resistance:  EPS geofoam is engineered for high strength with compressive resistance values of 317-2,678 lbs./sq.ft. at a 1-percent strain.  The material’s Westergaard modulus of sub grade reaction “k” values indicate that EPS geofoam has better bearing capacity than most foundation soils.  As long as combined dead/live loads do not exceed 1-percent strain, the material will not creep or experience plastic yield.

Buoyancy:  Although this is not an issue in most applications because EPS geofoam is buoyant, it is important to consider uplift forces in applications where the material will be partially or fully submerged.  Buoyancy can be minimized by installing geofoam above the water table and ensuring suitable drainage.  Additionally, the surcharge from overlying soils or pavements is frequently sufficient to offset uplift forces.  Where high water exposure cannot be avoided, supplemental restraints like restraining straps might be required.  The fact that the material’s buoyancy can be readily addressed is seen in its successful use in several levees in the U.S.

Damaging Elements:  EPS geofoam does not decompose, nor is it affected by freeze-thaw cycles or road salts, and is considered  permanent in civil engineering applications.  Petroleum products and other chemicals can damage EPS, so geofoam designs should include a compatible geomembrane or a continuous load distribution slab to protect the material from fuel spills or exposure to hydrocarbons in contaminated soils in applications where these conditions might exist.  EPS is combustible, so it is important to check with the particular manufacturer if the geofoam includes a flame retardant.  Flammability is typically only a concern if open flames are present during installation, as geofoam is usually isolated by membranes, soils or pavement in the finished application.

Working With Geofoam

EPS geofoam greatly simplifies site prep, because it does not require the surcharging, preloading or staging often necessary with other fills.  The material is also easy for crews to place by hand or with small mechanical equipment.  A reputable geofoam manufacturer will provide contractors with detailed information on working with the material, and producers like Insulfoam will provide on-site consultations.

…geofoam is lightweight, durable, easy to use and more consistent that other fills…

Geofoam installation does not require much training.  Among the installation factors to keep in mind:

  • Sizing:  Standard-size blocks are 4 ft. by 8 ft., at various thicknesses.  A well-equipped manufacturer can produce custom sizes and shapes to meet any project need, or crews can easily trim geofoam on the job site using a hot wire cutter (which some manufacturers will supply) or with handsaws or chainsaws.
  • Block Placement:  Typical geofoam designs call for installing the blocks on a level course of sand, pea gravel or any locally available permeable leveling course material.  Similar  to how brick walls are configured, geofoam blocks usually are staggered so their joints are offset and not located in the same vertical plane.  Depending on the engineering requirements, the blocks can be interconnected with either barbed plates or polyurethane adhesive.
  • Wind Protection:  Geofoam is lightweight, so it is important contractors weigh or tie down stockpiles on windy job sites.

A Wide Range of Applications

Crews with Walsh Construction use EPS geofoam as an ultra-lightweight yet durable fill to form the hills and valleys that will comprise Maggie Daley Park on Chicago's waterfront.

Crews with Walsh Construction use EPS geofoam as an ultra-lightweight yet durable fill to form the hills and valleys that will comprise Maggie Daley Park on Chicago’s waterfront.

Because geofoam is lightweight, durable, easy to use and more consistent than other fills, it is being used by building professionals as a fill alternative in numerous large civil projects, as well as in residential and commercial buildings.  Among example installations:

  • I-80 / I-65 Interchange, Gary, Ind,:  To reduce excavation volumes of high-organic content soils at the south end of Lake Michigan, Walsh Construction instead used EPS geofoam for the road sub grade.  “There’s no comparison to using traditional fill,” says Walsh Construction site supervisor Gary Walsh.  “There are no lifts needed; we just unloaded the blocks and it installed fast.”
  • Alaskan Way Viaduct, Seattle, Wash.:  The Seattle waterfront has notoriously soft soils, since much of the downtown area was built on fills created by re-grading the city in its early days.  As part of embankment construction for the Alaskan Way Viaduct replacement, project engineers had to ensure that new ramps would not induce settlements on the underlying soft soils, which could impact the stability of adjacent elevated structures.  EPS geofoam provided the necessary load support at a low weight and eliminated the need to surcharge the soil.
  • CRH-UBH Freeway Interchange, Valsayn, Trinidad:  As discussed in an earlier Site Prep article (“Standing on Solid Ground,” March, 2014), contractors used geofoam as a lightweight embankment fill on top of the pile cap for an existing flyover ramp pier, to avoid any modifications of the pier’s seismic behavior in the earthquake prone region.

Beyond such road applications, geofoam is an ideal lightweight void fill on vegetated roofs, which is a similar application to the landscape contouring of Maggie Daley Park on top of the East Monroe Street Parking Garage in the heart of Chicago.

Geofoam for Utility Protection and Utility Insulation

Pipeline

Corroded Alyeska Pipeline

For years the problem of corrosion has been on the minds of the engineers who manage the Alyeska Pipeline, a pipeline that transports oil from the fields on the North Slope of Alaska.  One of the several mountain passes that connects the oil-producing areas of the North Slope with interior Alaska and the south is Atigun Pass…some of the most beautiful country on the planet; however, the harshest as well.  Atigun Pass is located at an elevation of 4,739 feet above sea level and is the highest pass in Alaska that is maintained though out the year.  The weather is harsh and highly unpredictable providing many challenges such as freeze thaw cycles and high concentration of seasonal moisture.

The problem was in the original design.  Rigid flat stock was originally used to insulate below grade transitions of the Trans-Alaska Pipe Line.  Over the years the extreme arctic conditions exposed the problem.  Freeze thaw cycles and high moisture destroyed the XPS application.

EPS Goefoam was the perfect solution for this problem for both utility protection and utility insulation simultaneously.  Custom cut geofoam pipe jackets were the answer with low moisture absorption, light weight for ease of installation, stable thermal protection and locally produced.  Geofoam solves a decade long problem for decades to come and extending the life of the Trans-Alaksa Pipe Line one transition point at a time.

Custom

Custom cut geofoam pipe jackets

Cu

Custom cut geofoam pipe jackets

 

 

 

 

 

 

 

MORE:

New Below Grade Data Released:  EPS vs. XPS Insulation:  The EPS Industry Alliance (EPS IA) has released NEW moisture absorption data regarding XPS, moisture absorption and the effects on R-Value through the latest Technical Bulletin, EPS Below Grade Series 105:   XPS Insulation Extracted After Field Exposure Confirms High Water Absorption & Diminished R-Value, March 2014 (pdf)

INSULFOAM QUESTIONS

Bernard Droege, Insulfoam Territory Manager

Bernard Droege, Insulfoam Territory Manager

 

Contact Bernard Droege, Insulfoam Territory Manager

Bernard.Droege@insulfoam.com

Connect with Bernard on LinkedIn

Read more on Insulfoam.com

Geofoam Solves Manhole Soil Erosion & Displacement Problem

Manhole jacking and separation

Manhole jacking and separation

Problem:  Deep water and winter freeze cause manhole jacking and separation.

A manhole located in Class ‘A’ wetlands in the city of Anchorage AK., experiences severe frost damage. Adjacent to a creek and subject to high water table and deep winter freezing, over the years frost pulled the manhole apart causing the lid and grade rings to fall off, the cone section to tilt 35° from vertical, and the 4” thick reinforced concrete barrel section broke away from the base, allowing ground and surface water to flow freely into the manhole. End result, soil erosion around the manhole and in the winter months, jacking of the manhole sections and displacement.

Solution:  To stop the jacking and the movement EPS Geofoam acts as an insulated concrete form and later as a compressible inclusion virtually eliminating the jacking around, separation and erosion.  EPS Geofoam in earthworks applications provides the benefit of reducing both vertical and lateral pressures on below ground structures.

Geofoam installation

Geofoam installation

Geofoam, insulated concrete form

Geofoam, insulated concrete form

 

 

 

 

 

 

 

 

 

 

 

 

Geofoam Benefits:

Cost effective

  • Reduces associated structural costs

Labor Savings:

  • Does not require surcharging, preloading or staged construction
  • No secondary compaction required
  • Not weather-dependent- can be installed during rain or snow
  • Does not require heavy equipment to move
  • Ease of installation, ease of cutting

Product Attributes:

  • Available in job-specific block sizes
  • Engineered per project specifications – can match compressive resistance with job requirements

INSULFOAM QUESTIONS

Bernard Droege, Insulfoam Territory Manager

Bernard Droege, Insulfoam Territory Manager

Contact Bernard Droege, Insulfoam Territory Manager

Bernard.Droege@insulfoam.com

Connect with Bernard on LinkedIn

Read more on Insulfoam.com

Lighten Up

Originally posted online at Constructor Magazine, Web Exclusive

USING GEOFOAM TO SIMPLIFY COMMON SITE PREP CHALLENGES

Projects built with geofoam include road beds, bridge approaches, levees and other jobs.

Projects built with geofoam include road beds, bridge approaches, levees and other jobs.

Contractors have successfully used expanded polystyrene (EPS) geofoam to simplify site preparation since the 1960s. Projects built with the material include road beds, bridge approaches, levees and other civil jobs. Now, geofoam is increasingly solving a host of construction challenges in commercial buildings and large residential applications.

GEOFOAM OVERVIEW
Geofoam is an ultra-lightweight, engineered, closed-cell rigid foam. The material is about 100 times lighter than soil and weighs substantially less than other lightweight fills.

Even though it is very light, geofoam is high strength, with compressive resistance values of 317 to 2,678 lbs/ft2 at a 1 percent strain. Geofoam is suitable for a range of heavy loading conditions, including sub-base for pavements and railroads bearing jet aircraft and locomotives.

EPS geofoam changes the traditional soil compaction phasing method in which contractors mechanically compact soil to a percentage of dry density and pay for multiple samples and laboratory tests. Unlike other lightweight fills such as shredded tires or wood chips, EPS geofoam is homogenous, which provides uniform load transfer and eliminates differential settlement.

GEOFOAM APPLICATIONS AND BENEFITS
The combination of lightweight and high strength makes geofoam the ideal material for many building applications, including:
• Creating level building pads on steep-sloped lots
• Stabilizing steep slopes
• Remediating soft soils
• Forming swimming pools and pool decks
• Landscaping
• Creating theater/stadium seating

Creating level building pads on steep-sloped lots
Given its lightweight, contractors can use geofoam to simplify construction of retaining walls needed to level steep-sloped lots. Geofoam drastically reduces or can eliminate the lateral load on retaining walls, so walls do not need to be as robust. Material and labor costs are much lower due to reducing forming, structural steel and concrete volume, and lessening or eliminating the need for geogrids or mechanical tiebacks.

Eckhart Construction Services, a Carolinas AGC member, used geofoam to create a level building site for a McDonald’s restaurant. There, a retaining wall was needed that could accommodate the change in grade, as well as reduce the load over extremely soft soils. Typical soil fill would have caused unacceptable settlement of the retaining wall. The use of EPS geofoam allowed for incorporation of a traditional keystone retaining wall while eliminating the need to use the typical geogrid material to reinforce the retaining wall.

Stabilizing steep slopes
Geofoam’s lightweight makes it an excellent option for stabilizing steep slopes, without the need to change the final slope geometry. Since the material is much lighter than other fills, it greatly reduces the weight of a slope’s driving block and lowers the risk of costly and dangerous landslides. An additional advantage of using lightweight geofoam blocks on slopes is that crews can move and place them by hand. This eliminates the need for heavy earth moving and compaction equipment on steep and uneven terrain.

Remediating soft soils
Ground with soft soils or soft clay makes building construction notoriously difficult. To eliminate or greatly reduce the need for time-consuming and costly surcharging of soft soils, EPS geofoam provides high load support at a low weight for projects of all sizes.

An example is the renovation of an existing office building into a city hall in the Pacific Northwest. Building codes required installation of new handicap ramps as part of the upgrade. The challenge was the project site is situated on extremely soft glacial till at the south end of a lake. As such, the ramps needed a very lightweight void fill to avoid post-construction settlement. After evaluating various lightweight fill options, the project team chose EPS geofoam. Crews installed 5,000 cubic yards of geofoam, which played a role in helping the project be completed two months ahead of schedule and nearly $600,000 under budget.

Forming swimming pools and pool decks
Contractors use geofoam to simplify construction of swimming pools in residential, commercial and institutional uses, including hotels, schools and community centers. Project teams can order the blocks pre-cut to precise dimensions or can easily cut them to size and shape on site. This simplifies the concrete forming process, and greatly reduces weight for construction of rooftop pools or on sites with poor load-bearing soils. Once crews form the pool basin and decks with geofoam, they can apply shotcrete directly to the foam.

Landscaping
Because crews can readily form geofoam into a host of shapes, the material provides a simple way to create landscape topography and berms. This is particularly beneficial when loads must be minimized on underlying structures and utilities. Examples include rooftop gardens and landscaped spaces with shallow buried utilities that cannot bear the weight of soil fills.

Creating theater/stadium seating
Geofoam provides contractors a fast and simple way to change slopes within buildings – either creating tiered seating as in auditoriums, movie theaters, churches or gymnasiums, or leveling out such a sloped space for other uses.

For stadium style seating, crews hand place row upon row of geofoam blocks to achieve the necessary profile. They can then either place concrete over the geofoam as shotcrete or as pre-cast panels. Using geofoam greatly simplifies the forming process and eliminates the need for complex tiered compacting of soil to form the stepped profile of stadium seating.

Crews can also use geofoam to quickly level an existing sloped elevation in a building. For example, a university wanted to convert a sloped floor lecture auditorium into a surgical suite at a hospital. The project engineers specified EPS geofoam as a structural void fill to reverse the slope. The EPS supplier cut the blocks to minimize field fabrication on the job site. Because the enclosed auditorium did not have space to accommodate heavy equipment, and as noise from mechanical compaction of soil would have disrupted hospital patients and staff, geofoam was an ideal alternative. The lightweight structural fill provides a strong, stable sub-base for the new, level concrete floor slab.

WORKING WITH GEOFOAM

Even though it is very lightweight, geofoam is high-strength and suitable for a range of heavy loading conditions.

Even though it is very lightweight, geofoam is high-strength and suitable for a range of heavy loading conditions.

Although geofoam can be manufactured in many sizes and shapes, standard blocks are typically 4 feet wide by 8 feet long, and of varying thickness. If contractors do not order geofoam precut to specified dimensions, they can easily trim geofoam to size using a hot wire cutter (which some manufacturers will supply) or with a handsaw or a chainsaw onsite.

When placing geofoam, the blocks are staggered so their joints are not located in the same vertical plane. At times, the blocks are interconnected with either barbed plates or polyurethane adhesive, in accordance with engineering specifications.

Due to geofoam’s lightweight, crews can maneuver and place the blocks by hand or with small mechanical equipment. A typical installation is to place geofoam blocks on a level course over sand, pea gravel or any locally available permeable leveling course material.

Following are points to keep in mind when working with geofoam:

• Geofoam is subject to damage when exposed to certain hydrocarbon chemicals or solvents. If needed, crews can protect the material with hydrocarbon-resistant geo-membranes or concrete slabs.

• Manufacturers treat geofoam with a fire retardant to avoid the rapid spread of fire. However, the material is combustible at high temperatures, so it is important to be cautious when conducting hot work, such as welding, around geofoam.

• Exposing geofoam to sunlight for extended periods can cause superficial discoloration, which does not impact the product’s integrity and can be removed with a broom or very light pressure-washing, if desired.

• Because geofoam is lightweight, it is important to take care when stockpiling the material on job sites where windy conditions exist. Contractors should weigh or tie-down stockpiles, as necessary.

CONCLUSION
Soil fills will continue to factor prominently in construction given their ubiquity and familiarity, but for challenging projects, geosynthetics like geofoam are increasingly popular. Geofoam offers contractors a simple-to-use, engineered alternative to traditional earthen fills. The material solves a host of site preparation challenges in commercial and large residential building projects.

Maggie Daley Park to Turn Garage into Rolling Hills- ABC Chicago News

More news coverage on the use of InsulFoam Geofoam in Chicago’s newest and biggest downtown attractions, Maggie Daley Park. When complete, the new park will have a distinctive presence with signature elements like rock-climbing sculptures, an ice-skating ribbon, and play garden.  Read more in the latest and on-going news coverage on details and view the project’s job site camera:

Geofoam Helps Mold the Construction of Chicago’s New Downtown Maggie Daley Park.

-  Foam Blocks Form Hilly Landscape at Maggie Daley Park Site, Chicago Sun-Times

Originally aired and published on  ABC 7 Chicago News, by Paul Meincke

chicago abc_maggie daleyBuilding a park on top of a parking garage is an engineering question whose answer rests with the new Maggie Daley Park on Chicago’s lakefront.

In the shadow of towers made of concrete and steel, there are building blocks of a different sort. Thousands of them are being layered together to give shape to what will be Maggie Daley Park.

“We’re going to transform what was a flat, sort of uninviting area into a gem for Chicago that compliments Millenium Park,” said Chicago Park District CEO Michael Kelly.

That transformation has a lot to do with topography. When this 20-acre park is done, its northeast corner will sit 30 feet higher than the southwest. That’s a lot of dirt. And dirt weighs a lot. And a lot of weight would not be welcome atop the two story parking garage that sits directly underneath. So, what do you use? Geofoam.

“Geofoam is essentially Styrofoam. It’s lightweight fill,” Kelly said

It’s 100 times lighter than soil. Geofoam isn’t a new concept. It was used here before, but there’s a lot more of it now, 75,000 cubic yards of it will be sculpted and tacked down to create a rolling terrain.

On top of the geofoam goes the dirt which will be deep enough in spots to accommodate the roots of one-thousand new trees. If you’d never seen the geofoam going in, you’d never know it was there.

“That’s essentially the best compliment we could get once this park is open and that is that people don’t realize that it’s a park constructed on top of a garage,” said project engineer Nichole Sheehan. “It’s a park that people are going to love and hopefully come to all the time.”

The park district has been recording its birth with time lapse camera, from barren garage roof to the building of baby hills, and when the park’s soft opening comes next fall, this is the vision. Three of the 20 acres devoted to a children’s playground. Just up the path, a 25 foot climbing wall, and when the cold months come, a feed of built in refrigerant will convert that path into a 400 meter ice skating ribbon – attracting old Hans Brinkers or perhaps young Blackhawks.

From debris dating back to the great Chicago fire to geofoam, this piece of Chicago has undergone remarkable change over the years.

In the late 40′s and early 50′s, there were lots of railroad, lots of parking that over the years goes went away or went underground.

“Somewhere way down there, there’s fill,” Kelly said. “There’s probably some old railroad scrap. Now we’re standing on geofoam and we’re building a green park. We’re building a 20 acre green roof is essentially what we’re doing with a thousand trees.”

The first of the trees come soon. The grand opening of Maggie Daley Park comes next Spring. Its birthing thus far carries four words welcomed in urban re-design.

Maggie Daley Park carries a roughly $55 million price tag. Most of that comes from parking garage lease money and private contributions along with five million in park district capital funds.

 

EPS: Not Just for Insulation Anymore

Moller Field

Moller Field

Moller Field, Geofoam Installation

Moller Field, Geofoam Installation

Expanded polystyrene (EPS) Geofoam has been used as a geotechnical material since the 1960s. EPS Geofoam is approximately 1% the weight of soil and less than 10% the weight of other lightweight fill alternatives. As a lightweight fill, EPS Geofoam reduces the loads imposed on adjacent and underlying soils and structures.

Moller Field, Geofoam Installation

Moller Field, Geofoam Installation

Sitka Alaska has found a solution to an ever present engineering challenge. It’s not just another tool in the tool box, it is the tool… EPS Geofoam. The Geofoam solution has made the reconstruction of Sitka’s Moller Field, the “Field of Dreams”. Dating back to the 50′s, it was considered the premier baseball field of Southeast Alaska. Over its history it became a horrible marsh due to the deep poor soils it was built on. Today it is the only all-turf field in Alaska.

The field’s reconstructionsuccess was due in large part to Geofoam. Geofoams’ use reduced the overall weight of the field and gave rigidity to the otherwise waterbed like third class field that it was. Today it is the field the rest of the state wished it had.

More Geofoam articles and profiles:

INSULFOAM QUESTIONS

Bernie

Bernard Droege, Insulfoam Territory Manager

Contact Bernard Droege, Insulfoam Territory Manager

Bernard.Droege@insulfoam.com

Connect with Bernard on LinkedIn

Read more on Insulfoam.com

Project Profile: Idaho Bridge Expansion & Replacement

Topaz Bridge Expansion & Replacement  |  McCammon, Idaho  |  View Project Profile (pdf)

Idaho’s heavily used trucking route and bridge (circa 1940) expands from 2 to 4 lanes to increase safety and capacity using InsulFoam Geofoam.

Geofoam blocks were used to construct a new 500 foot long, 30 foot tall EPS block embankment.  The new embankment supports the US-30 road expansion and its approach to the new Topaz bridge - notably the longest span in the state of Idaho.

Geofoam blocks were used to construct a new 500 foot long, 30 foot tall EPS block embankment. The new embankment supports the US-30 road expansion and its approach to the new Topaz bridge – notably the longest span in the state of Idaho.

Topaz Bridge

The pavement section is constructed on top of the 45 foot tall combined soil & Geofoam block approach fill

Idaho Transportation Department’s first EPS Geofoam project was designed by Terracon Engineers and JUB Engineers of Boise.  EPS was specified as a soil replacing embankment fill material due to poor foundation soils and 2 steel fish culverts that could not bear the weight of traditional soil fill.  A new three-span, bridge replaced the existing bridge (from the 1940′s) crossing rail road tracks and expanding the highway to 4 instead of 2 lanes.  23,000 cubic yards of large block EPS was installed by Scarsella Brother Inc. and supplied by Insulfoam.

THE PROBLEM

The expansion of the US-30 and bridge replacement required a new fill embankment to support the new roadway and bridge approach on a very steep side slope.

The new (600 ft long) expanded bridge clears The Pontneuf River as well as the Union Pacific Railroad tracks, and required a new higher grade of both the bridge structure and the existing roadway to support the new wide and long center spans.

EPS

EPS block fill is partially installed, during bridge construction.

As a result the new bridge approach embankment would be 45-50 feet high, too costly to be retained by conventional concrete cantilever or MSE wall, and raised concerns about global stability.

Further challenges to the project design were the site conditions.  Located adjacent to the Portneuf River, shallow bedrock and loose or soft sediments underlie the new approach embankment.  This both challenged the new roadway embankment’s strength and stability, and limited deep foundation designs required with concrete walls.

THE EPS GEOFOAM FILL SOLUTION

To reach the new bridge’s approach embankment height of 45 feet, engineers chose a combined fill solution.  The lowest 15 feet was a small earthen embankment, while InsulFoam GF constituted the upper 30 feet.  4 1/2 feet of granular fill retained in wire gab ions and an asphalt pavement section were installed directly on top of the EPS blocks to complete the full height of the new embankment.

Custom fabricated "tongs" grip the large EPS blocks without damaging them.

Custom fabricated “tongs” grip the large EPS blocks without damaging them.

The exposed vertical face of the EPS is eventually covered with a protective shotcrete facing.

The exposed vertical face of the EPS is eventually covered with a protective shotcrete facing.

 

 

 

 

 

 

 

 

 

The soft sediments underlying the site required the lower earthen embankment to settle (80 days), but the InsulFoam GF block fill required no additional surcharge time or secondary compaction by the contractor.  Traffic moved on the existing roadway throughout the installation of the upper embankment, which was a key factor for the expansion to finish when weather conditions permitted.

Net

Near “Net-Zero” surcharge loads.  The void in between the blocks and the native slope was filled with sand.

The ultra lightweight nature of EPS allowed the total design weight of the tall embankment to be week under the bearing capacity of the poor foundation soils which aided ITD in successfully completing their first EPS Geofoam project.

Geofoam Lightweight Geo-synthetic Fill:

  • Soft Soil Remediation
  • Lateral Load Reduction
  • Slope Stabilization
  • Buried Utility Protection
  • Structural Void Fill
  • Predictable Elastic Modulus
  • Exceptional Strength & Stability
  • Exceeds 75 year Design Life
  • Weather, Insect & Mold Resistant
  • 100% Recyclable

 

MORE GEOFOAM SOLUTIONS IN HIGHWAY CONSTRUCTION

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Foam blocks form hilly landscape at Maggie Daley Park Site, Chicago Sun-Times

Great story in the Chicago Sun-Times about the use of InsulFoam Geofoam in Chicago’s newest and biggest downtown attractions, Maggie Daley Park.  This is a very large geofoam project, the new park will have a distinctive presence with signature elements like rock-climbing sculptures, an ice-skating ribbon, and play garden.  Read more details and view the project’s job site camera:  Geofoam Helps Mold the Construction of Chicago’s New Downtown Maggie Daley Park.

Originally published on Chicago Sun-Times, suntimes.com, by Tina SFondeles

Geofoam

Maggie Daley Park is being formed using GeoFoam, a plastic foam substance that has been used once the ’80′s to create landscape and hills on others flat land.  - Brian Jackson  |  Sun-Times

Chicago’s shoveling days should be over, but the future Maggie Daley Park kind of looks like a winter wonderland, full of white building blocks.

Those giant blocks of Geofoam will transform flat land into a hilly landscape at the park site, which spans 20 acres and is bordered on the west by Columbus, the north by Randolph, the south by Monroe and the east by Lake Shore Drive.

Landscape architects say the lightweight, cost-effective, environmentally safe and recyclable fill material is key to creativity. The expanded polystyrene is being used around the world and locally to contour flat Midwestern land.

At Maggie Daley Park, crews are using old Geofoam — already part of Daley Bicentennial Plaza — and a lot of new blocks to shape the park. From various vantage points around the park, onlookers can watch as the foam is delivered every day — six truckloads — and crews have already filled the northeast and northwest corners of the park, and are moving south.

The foam installation will be done by early summer. By September, dirt will be placed over the foam. It’s even being used for the park’s ice skating ribbon.

“For the ice ribbon, you’ve got up and down. It’s not just flat,” said Lowell Zarzueta, of Walsh Construction, who is overseeing part of the second phase of the project. “For you to go up high, you almost have to skate super fast, just to get over that little hump.”

He said the foam is being used to create a hill that will be even with Randolph Street, making it easy for people to come into the park. There are also peaks at the northeast corner, where a picnic area is being built.

“With Maggie Daley Park, you’re going to have hills. The park will offer these beautiful vistas of Lake Michigan, which it never had there,” said Bob O’Neill, president of the Grant Park Conservancy. “In order to do that, to get these hills, and these rolling meadows over a whole flat area in Chicago, to get any topography, especially on top of a structure, you need Geofoam.”

Crews on Friday said deliveries of Geofoam are about half done. The mass quantity of snow Chicago received this year did slow work a bit, but crews said phase two of the park — earthwork, utilities, paving, architectural and program elements, soil placement and planting — is on schedule for completion in October.

Here’s how crews are layering the park: First it was excavated, the dirt placed in nearby Peanut Park to be reused. Tar was put over the garage, then a layer of black tarp. It’s then tested to make sure it’s waterproofed to prevent leaks to the garage below. Four inches of stone are placed on top, and then the foam is placed with yet another black tarp over it. Dirt will go over the foam.

Come next spring, the ground will become green again, as landscaping and planting will be in full swing.

This isn’t the first time the product has been used in Chicago. It was also used for the Daley Plaza renovation — where the trees are now planted, and for the Soldier Field remodeling, where Geofoam was placed as fill over the garage, creating a hilly and grassy landscape near Soldier Field and the Field Museum.

Peter Schaudt, the landscape architect behind both renovations, said Geofoam played a major role in the projects.

“I think it allows you the freedom to be creative,” said Schaudt, of Hoerr Schaudt Landscape Architects. “It allows you to really model the land in an artificial way, and the great thing is when you put the soil and lawn and trees on top of it, it’s an illusion.”

The product also is very strong, he said. “It never dematerializes. It stays the same size. At Soldier Field, it was used to support 18,000 pounds.

“It’s much more substantial than just putting a thin veneer over a roof, and it allows you to create a lot of great and dramatic changes,” Schaudt said.

A soft opening for the $55 million park, named for the late wife of former Mayor Richard M. Daley, is scheduled for fall, and the park will be officially completed by spring 2015. A park district website, maggiedaleyparkconstruction.org features two webcams to view the construction.

Email: tsfondeles@suntimes.com  |  Twitter: @TinaSfon

Applications, Design & Construction Considerations for EPS Geofoam

Originally posted on CE News online in Progressive Engineering

Geofoam: A lightweight fill alternative

Pacific Bridge

To widen the Pacific Street Bridge over I-680 in Omaha, Neb., Hawkins Construction excavated the soil between the existing abutment wall using EPS geofoam as lightweight backfill for the bridge approach.

Geofoam is a rigid, engineered, lightweight fill material typically made of expanded polystyrene (EPS). For fills, a key advantage of EPS geofoam is its low weight — approximately 1 to 2 percent the weight of soil. Typical densities for EPS fill are between 0.7 and 2.85 pounds per cubic foot, therefore maintaining a predictable compressive strength that is suitable for many structural applications (see “Geofoam physical properties”).

Today, geofoam is fully recognized and accepted as a lightweight fill alternative and has seen increased use in commercial and residential applications. Since the first installation of geofoam in 1965 (see “A short history of geofoam”), numerous projects around the world that have relied on the material to solve construction problems.

Given EPS geofoam’s low weight, strength, and ease of use, more project teams are using it to solve regular construction challenges in five basic applications.  Read the full article featured on CE NEWS as our Geofoam Specialist, Nico, discusses:

  • The five basic applications and specific project examples:  1.)  Lateral load reductions on structures  2.)  Soft soil remediation  3.)  Slope stabilization  4.)  Lateral and dead load reductions over buried utilities  5.)  Lightweight structural void fill.
  • Geofoam physical properties
  • Short history of geofoam
  • Construction considerations
  • Cost saving advantages

Utilizing Geofoam in Foundation Design for Steep Sloped Lots

Foundation Design Layout

Foundation Design Layout

A custom high end home was built on a very steep hillside lot overlooking Lake Washington near Seattle.  The owner of this home owns an excavation/gravel business.  He has all of the heavy equipment and free soil he could ever want, yet he chose to backfill three foundation walls with geofoam.  This project was originally designed with a compacted soil backfilled MSE wall that would have to be trucked down 95′, through a country club and from the top of the hill.  The amount of concrete, reinforcement, tie backs and forming costs that were removed from the foundation design more than paid for the geofoam and reduced the total weight of the import fill material by over 2 million pounds.

 

Geofoam Installation, Lake Washington Residence

Geofoam Installation, Lake Washington Residence

Benefits that lead to overall project cost savings by using geofoam as an alternative to traditional soil fill:

  • Geofoam is easily installed and the lightweight nature of geofoam allows it to be maneuvered by hand and used on projects with tight construction access where the use of larger mechanical equipment may not be feasible.
  • Shotcrete, Gunite, or soil can be placed directly against geofoam eliminating the need for expensive forming.
  • Construction traffic and import costs are minimized, as 1 flatbed truck of geofoam is equivalent to approximately 12 dump truck loads of traditional fill.
  • Congestion on the roads or road closures leading in and out of a project site is minimized.
  • The construction time of a project is reduced as several feet of geofoam can be placed in a fraction of the time that it would take to the place and compact traditional soil fill in the required 8 to 12-inch lifts.  As an added incentive, geofoam does not require compaction testing like tradition fill.
  • Decreased maintenance costs as a result of less settlement issues from the low density geofoam.
  • Tight construction scheduling can easily be maintained using geofoam as it can be installed during any type of weather or site conditions.
  • Geofoam is extremely eco-friendly and geofoam blocks can be re-used in other projects or be recycled.
Geofoam Installation, Lake Washington Residence

Geofoam Installation, Lake Washington Residence

Geofoam Installation, Lake Washington Residence

Geofoam Installation, Lake Washington Residence

Lightweight Geofoam Fill Supports Highway Construction

Originally posted on SitePrep online, March 2014

Working in the soft soils of Trinidad, the contractor specified EPS geofoam to reduce the load applied to the pile cap under the existing pier on this freeway interchange project.

Working in the soft soils of Trinidad, the contractor specified EPS geofoam to reduce the load applied to the pile cap under the existing pier on this freeway interchange project.

Although greenfield site preparation can involve a host of geotechnical challenges, in urban areas the need to work around existing infrastructure presents its own costly and complex design problems.

A new freeway interchange at Valsayn on the Caribbean island of Trinidad provides a clear example of the potential difficulties.  Traffic growth in the island nation required the development of a new grade-separated interchange between two primary highways – the Churchill-Roosevelt Highway (CRH) and the Uriah Butler Highway (UBH).

One challenge the project team faced was that the north and southbound lanes of the UBH needed to pass adjacent to (and on both sides of) a support column for an existing flyover ramp.  The new lanes required pavement of 9.8 to 10.5 ft. of embankment fill on top of the pier’s pile cap on very soft soils.  A concrete shaft of seismic activity.  The concrete shaft also keeps the pier in depended for the the new fill.

Designing infrastructure to mitigate earthquake damage is crucial in Trinidad, which lies near the boundary of two tectonic plates.  The island has been impacted by five earthquakes greater than magnitude 7.0 since the 1700s, including a 7.3 quake in 2007.

To reduce the load applied to the pile cap under the existing pier, and to avoid any modification of the pier’s seismic behavior, contractor Vinci Construction Grands Projects specified InsulFoam GF expanded polystyrene (EPS) geofoam as a lightweight fill.  Goefoam offers high compressive strength and predictability, yet weighs up to 100 times less than traditional soil fills depending on the EPS density selected.

EPS geofoam fill provided a cost-effective alternative to building a concrete slab founded on piles to support the load from the road and transfer it away from the pier pile cap.

EPS geofoam fill provided a cost-effective alternative to building a concrete slab founded on piles to support the load from the road and transfer it away from the pier pile cap.

Vinci Construction Grands Projets crews placed 2,100 cu. yds. of EPS22 geofoam fill in an 80 by 89 ft. area surrounding the pier in only three-and-a-half days. “Because of the ease and speed of installation, using geofoam allowed us to build this fill two times faster than a regular sand fill, especially in Trinidad where heavy rains can interrupt back filling activities for days,” says Cecile Huillard, construction engineer with Vinci Construction Grands Projets.

Huillard notes the use of EPS geofoam fill provided a cost-effective and simple alternative to building a concrete slab founded on piles to support the load from the road and transfer it away from the pier pile cap. No heavy equipment was needed for the fill placement, as crews were able to install the geofoam blocks by hand. Additionally, the geofoam resulted in lower and smoother post-construction differential settlements of the roadway in both the transversal and longitudinal directions. The use of geofoam also eliminated the need for additional geotechnical investigation for potential additional piles.

Using EPS geofoam as a lightweight fill reduces labor and material costs without the need for over-excavation.

Using EPS geofoam as a lightweight fill reduces labor and material costs without the need for over-excavation.

EPS geofoam does not typically require surcharging, preloading or the staging often necessary with other fills. It resists moisture, freeze-thaw damage, insects, mold and decomposition. The product is inert, does not emit undesirable gases or leachates, and is reusable or recyclable. EPS geofoam is available in multiple strengths suitable for a wide range of engineered applications. The EPS22 geofoam specified in the CRH/UBH interchange project has a compressive resistance of 1,051 psf at 1-percent deformation.

In addition to soft soil remediation and reducing vertical loads on existing infrastructure and utilities, engineers have used EPS geofoam to solve a range of other geotechnical challenges, as outlined in the adjacent article, Applications for Lightweight Geofoam Fill.

Applications for Lightweight Geofoam Fill

Given EPS geofoam’s low weight, strength and ease of use, more project teams are using it to solve regular construction challenges in five basic applications:

1. Eliminate or reduce lateral loads on structures.

2.     Create a zero loading factor for soft soil remediation.

3.     Lighten the driving block of a landslide for slope stabilization.

4.     Reduce lateral and dead loads over existing or newly buried utilities.

5.     Use as lightweight structural void-fill for numerous concrete and landscaping applications.

STRUCTURE LOAD REDUCTION

EPS geofoam significantly reduces lateral loads on retaining walls and building foundations. The material has an extremely low Poisson’s ratio (.05) and high coefficient of friction (.6), which helps enable placement of blocks in a way that replaces the sliding soil wedge above the angle of repose. By replacing the active wedge with EPS geofoam, which can be completely freestanding and self-supporting, project teams can save up to 75 percent of total project costs compared to traditional concrete walls designed to retain soil.

Using EPS geofoam also reduces labor and material costs without the need for over-excavation, and requires much less robust forming, reduced structural steel and concrete wall thickness, and fewer footings. The material can also reduce or eliminate the need for geo-grids and/or mechanical tiebacks. Project teams are able to construct a retaining wall with EPS geofoam paired with a lower-cost fascia (which acts more like a fence).

Another key advantage of using the material in retaining wall applications is the allowance for taller walls in narrower rights-of-way. This reduces time and cost spent on property acquisition, as well as minimizes lane closures and encroachment into wetlands or neighboring properties.

SOFT SOIL REMEDIATION

Ground with soft soils or soft clay makes construction difficult. These soft surfaces are notoriously poor foundations for many projects, and can require extensive remediation.

Instead of choosing costly (surcharging) and time-consuming remediation of soft soils, projects of all sizes can install EPS geofoam, which provides high load-support while maintaining a low weight.

SLOPE STABILIZATION

EPS geofoam’s low weight makes it an excellent option for stabilizing steep slopes, without the need to change the final slope geometry. As the material is much lighter than other fills, it greatly reduces the weight of a slope’s driving block and lowers the risk of costly and dangerous slope failures.

Additionally, since slope stabilization generally happens on steep and uneven terrain, using EPS geofoam simplifies construction, because crews can move and place it without heavy earthmoving and compaction equipment, thus greatly speeding up the construction schedule.

UTILITIES LOAD REDUCTION

Throughout the world, existing buried utilities create challenges for new construction. Notably, utilities frequently are not designed to have additional loads placed upon them. So, utilities either have to be moved or upgraded at high expense.

Instead, geofoam can be an ideal option to reduce dead and lateral loads on underground pipes, culverts and tunnels, while at the same time providing high thermal insulation values that protect against temperature fluctuations.

Another advantage is geofoam can protect utilities during seismic activity by reducing in-situ vertical/lateral stresses.

STRUCTURAL VOID FILL

Given its low weight, EPS geofoam is also well suited as a structural void fill in concrete forming operations. Crews can easily fabricate virtually any shape or slope, and the material eliminates separate concrete pours for vertical wall sections and topping slabs.

Applications include bridge column formwork, stadium seating in auditoriums and sports arenas, stairways, podiums, loading docks and rooftop pool decks. EPS geofoam can be manufactured into custom-cut blocks in various shapes and sizes to enable contractors to quickly build up these and other similar features.

Article featured on SitePrep 

“Because of the ease and speed of installation, using geofoam allowed us to build this fill two times faster than a regular sand fill, especially in Trinidad where heavy rains can interrupt back filling activities for days.”  - Cecile Huillard, Construction Engineer, Vinci Construction Grands Projects

Geofoam Saves Time, Money During Three Projects

Originally posted on Better Roads Magazine

I-80 / I-65 Interchange, Gary, Indiana

I-80 / I-65 Interchange, Gary, Indiana

The Federal Highway Administration (FHWA) has promoted the use of expanded polystyrene (EPS) geofoam as a lightweight embankment soil alternative for a number of years.  In a 2006 report, the agency’s Technical Service Team described the material as a “field-tested, budget-friendly winner.”  Why?  FHWA engineers list the following benefits:

  • Accelerated construction
  • Payroll, transportation and equipment cost savings
  • Reduced labor time for construction
  • Exerts little or no lateral load on retaining structures
  • Easily constructed in limited right-of-way situations
  • Allows application in adverse weather conditions.
Trinidad

Trinidad

The material is approximately 100 times lighter than soil, which save time.  Additionally, a single truck can carry approximately 120 cubic yards of goefoam versus 12 dump truck loads needed for an equivalent volume of earthen fill.  This reduces hauling costs, both in fuel and labor.  Geofoam is easy to install by hand, so it reduces expenses for heavy equipment.

Following is a discussion of tangible benefits derived from geofoam usage in real-world applications such as:

I-80 / I-65 interchange, Gary, Indiana:  FHWA recommended a net-zero load methodology for the roadbed to prevent post-construction settlement.

To reduce the amount of excavation of the high-organic content soils, the contractor, Walsh Construction, used EPS geofoam blocks.  A six-member crew installed 700 cubic yards of geofoam in one week working four- to five-hour days. The geofoam was delivered to the job site on 32 flatbed truckloads, whereas traditional fills would have required more than 400 dump trucks in the highly congested project area leading into and out of metro Chicago.

Highway Interchange, Valsayn, Trinidad:  The project team for an interchange between Trinidad’s Churchill-Roosevelt Highway (CRH) and Uriah Butler Highway (UBH), the island nation’s primary highways, used an EPS geofoam sub-base to solve an engineering challenge and save time in the process.

Highway geometry required placing new lanes adjacent to both sides of an existing fly-over ramp’s support pier. The grade for the lanes required placement of about 10 feet of embankment fill on top of the pier’s pile cap. Engineers determined that traditional fills would have caused unacceptable settlement of the compressive layers located below the fill.

To build the embankment while keeping loads down on the pile cap, Vinci Construction Grands Projets specified EPS geofoam as a lightweight fill, which provided an alternative to building a concrete slab founded on piles to support the load from the road and transfer it away from the pier pile cap. No heavy equipment was needed for the fill placement, as crews were able to install the geofoam blocks by hand.

The geofoam resulted in lower and smoother post-construction differential settlements of the roadway in both the transversal and longitudinal directions. It also eliminated the need for additional geotechnical investigation for potential additional piles. The ability to place the EPS geofoam during the rainy season was crucial to keeping the project on schedule. Crews placed 2,100 cubic yards of EPS geofoam in only 3.5 days.

Lake Cataouatche Pump Station Bridge, New Orleans, Louisiana:  The U.S. Army Corps of Engineers used EPS geofoam when it needed to build a service bridge over above-ground outlet pipes at the Lake Cataouatche pump station near New Orleans.

The bridge abutments are over extremely soft soil (compressible peat). A traditional soil embankment would have added substantial load to the underlying soils. To minimize loads on the soft soils, the project team used EPS geofoam under the bridge abutments.

Final thoughts

In addition to being lightweight, EPS geofoam has predictable elastic behavior and will not decompose. Further, unlike other lightweight fills such as shredded tires or wood chips, EPS geofoam blocks are homogenous, which provides uniform load transfer and eliminates differential settlement. All of these factors combine to make the material an ideal choice in many road sub-base applications at the federal, state and local levels.

Geofoam Helps Mold the Construction of Chicago’s New Downtown Maggie Daley Park

blog-banner_maggie-daley

Maggie Daley Job Site Cam, Dec 7th

Maggie Daley Job Site Cam, Dec 7th

With construction well underway the former Daley Bicentennial Plaza (next to Millennium Park) is on its way to being one of the “greenest” parks in America. The park is atop the large East Monroe Street Parking Garage, which has been restructured extensively including a new membrade above the garage which will also serve as the foundation that the park will sit on top of.

The new park, offers sweeping views of Lake Michigan, and combined with Millenium park “Peanut Park” will offer 45-50 acres of green roof over a downtown city parking garage.
***
So what does Insulfoam’s EPS Geofoam have to do with it? With about 60% of earthworks completes, crews have removed 82,000 cubic yards of existing fill (that existed beneath the soil for decades). Some of this is in fact lightweight fill material like Geofoam, and is still in excellent condition and is able to be recycled for reuse to create “hills” in the park. Geofoam will also support the base below new paths for bikers and walkers to get through to the lake paths.
Maggie Daley Park Rendering

Maggie Daley Park Rendering

The site itself now has the required EPS Geofoam blocks stock piled and ready for installation. In the days to come the installation of the acres of Geofoam will be seen on the bottom right hand side of THIS JOBSITE CAMERA.

Bob O’Neill, president of Grant Park Conservancy, in an article from the Chicago Sun Times called the park “more natural and much more informal” than Daley Bicentennial Park. And very kid-friendly, featuring a three-acre play garden, ice rink, climbing walls, a skating rink in the shape of a ribbon .“You’ll be able to walk up hills and see the lake,” O’Neill said. “When this is done . . . it’s going to be a much more green, sort of organic flow. Whereas Millennium Park is more structural and formal, this is more nature-oriented.”

EPS Geofoam used in environmental habitat restoration project

Photo_More Room To SpawnPROJECT TYPE:  Environmental habitat restoration

PROJECT GOAL:  Restore Salmon spawning groups by giving spring chinook and steelhead access for the first time in more than a century to 152 acres of wetland and five mountain streams cut off in 1893, when the Great Northern Railroad laid its track across Stevens Pass.  Both these species are threatened.

PROJECT LOCATION:  Chelan County, Washington State

GEOFOAM USE:  In order to create a building platform, InsulFoam Geofoam blocks were placed to serve as a track-side base that was topped with dirt to create a wider work area for crews and equipment during construction.

More room to spawn

Originally published in The Wenatchee World

by Christine Pratt (@CPrattWW), Energy, business and community reporter for The Wenatchee World

A half-dozen spring chinook nosed against a gentle current in the shallow, crystal waters of Upper Nason Creek early this month just downstream of history in the making.

Their offspring will, for the first time in more than a century, have access to a wetland and five mountain streams cut off when the Great Northern Railroad built its track across Stevens Pass in 1893.

The line severed an oxbow from the mainstem creek at a point that is today just across Highway 2 from the Nason Creek Campground rest area, 42 miles northwest of Leavenworth.

Culverts placed under the railbed let some water through, but have been an obstacle to the spring chinook and steelhead that once spawned in the creek’s upper tributaries. Both species are now threatened.

During spring runoff, the culverts concentrated and intensified the waterflow, creating too strong a current for young fish. As the summer warmed and flow ebbed, the culverts were left high and dry, blocking passage entirely.

That will end next month with the completion of the Lower White Pine Project, a restoration effort considered to have the highest potential for benefitting chinook and steelhead in the Wenatchee River subbasin.

BNSF Railway and Chelan County are using nearly $4 million in federal funding to restore flow to the old oxbow and its surrounding 152 acres of wetland. This will make 73 additional acres of streams and wetlands accessible to fish at periods of high flow and nearly 7 acres at low flow.

“This is a historical project. A precedent-setting project, and one of the only salmon-recovery projects that involves the railroad,” said Mike Kaputa, natural resources director for Chelan County.

Using nearly $1 million in funding from the Bonneville Power Administration, the railroad has replaced the section of track that once spanned the culverts with a bridge that it will own and maintain.

Crews worked for a month driving 16 steel pilings, each 155 to 200 feet long, down through the track bed to support the 90-foot concrete spans of the new bridge.

The work had to be carefully timed, so train service would not be interrupted.

An average of 20 trains carrying freight and people roll over those tracks daily, including Amtrak on its daily run from Seattle to Chicago.

“This is a critical rail corridor,” BNSF spokesman Gus Melonas said. “These projects take an extreme amount of planning, coordination and execution.”

With the bridge span in place, a Chelan County contract crew has excavated the earth from under the bridge, removed the culverts, and placed boulders along the new, under-bridge slopes. Work is expected to be finished next month, when temporary dams and silt barriers are removed and flow restored.

The resulting added habitat should produce more and stronger fish, better able to survive their epic migration to the Pacific Ocean to mature, and then the return trip to their home stream to spawn.

County biologists are hopeful that projects like this one on Nason Creek will boost available habitat to entice young fish to overwinter in their home tributaries, so they’re stronger and have a better chance of survival when they migrate to the ocean.

In early September, crews for Wenatchee contractor Hurst Construction were busy removing large “geofoam” blocks that had served as a track-side base that was topped with dirt to create a wider work area for crews and equipment.

Railroad crews were at work using special splicing machinery and sledge hammers to heat the rail sections white-hot and shape and join them together.

“It’s impressive to see these guys at work,” said Alan Schmidt, contracting officer for Chelan County Natural Resources, standing nearby. “It’s like good ol’ American ingenuity.”

Steven Seville, an engineer who works for the company that designed part of the project, agreed. “It was impressive to see the trains come through here this morning. The bridge is rock solid.”

The Lower White Pine Project is the first of three on Nason Creek that Chelan County hopes to coordinate in the coming years to open up more wetland upstream that is also blocked by the tracks.

No timeline yet exists for these proposed projects, Kaputa said, but they build on a county effort that includes barrier removal in 2007 and 2010 at two other points on Nason Creek, and a host of projects to restore side channels on the Wenatchee River.

Melonas said the railroad is open to additional projects.

“We’re pleased we were able to work closely with the state and county on this environmental habitat restoration,” Melonas said. “This will preserve wildlife opportunities and fish habitat and enhance the ecosystem… We’ll continue to discuss other projects in the future.”