City of Covington
SE 256th Street/164th Avenue SE Improvement Project
Project Statement
The SE 256th Street/164th Avenue SE Improvement Project consisted of both capacity
and safety improvements on two arterials in the City of Covington. The project widened
SE 256th Street from a 2-lane roadway with rural standards to a 5-lane urban arterial
standard. It widened 164th Avenue SE from primarily a 2-lane rural standard roadway to
a 3-lane urban arterial standard.
Project Summary
Prior to construction, both roadways had poor pedestrian facilities and thus poor walk
routes to Kentwood High School and Mattson Junior High which were within the project
limits. At the intersection of SE 256th Street and 164th Avenue SE was an existing
traffic signal without any left or right turn channelization which consistently backed up
during AM, PM and school peaks.
The project constructed over 3,000 lineal feet of 8 foot wide sidewalks connecting several
large housing developments directly to the two schools. In addition the project
constructed bike lanes on both roadways within the entire project limits. Construction
included more than 12,000 lineal feet of curb and gutter, 12,000 square feet of walls and
over 100,000 lineal feet of utility conduit.
Included in the project was the construction of a modern double lane roundabout at the
intersection of SE 256th Street and 164th Avenue SE replacing the traffic signal that was
controlling the intersection. During the design phase of the project there was significant
concerns and opposition to the installation of the roundabout from both citizens as well as
school officials.
The City held several public meetings with citizens as well as meetings with Kent School
District officials explaining the benefits of the roundabout. The city council supported
keeping the roundabout in the design and therefore proceeded to construction.
The project was awarded on May 16, 2006 to R.W. Scott Construction Company for
$10,463,533.86. The project consisted of a schedule A and schedule B with the
breakdown being $9,157,927.40 and $1,305,606.46 respectively. The schedule B work
was the result of an interlocal agreement with the Covington Water District (which is a
separate public agency from the city) to combine infrastructure needs of the two agencies
into one project.
In doing this the city was able to share the costs of items that would be common to both
projects if they were bid separately. Both agencies were able to share costs in items such
as traffic control, mobilization, erosion control, inspection, etc. The process was so
successful that we implemented it on two other projects that are currently under
construction.
As the project approached the construction of the roundabout, there was still considerable
public concern that the roundabout would not function well and there would be accidents
as students would not know how to drive the roundabout. In attempts to reduce the
concern and educate the public, city employees worked closely with the Kent School
District in distributing joint press releases and sending several flyers home with all the
students attending the two schools in the project limits.
When the roundabout was opened to traffic, city staff worked with the school district and
conducted a couple of presentations on “How to Drive a Roundabout” to all the bus
drivers and the PTSA. City staff also video taped a presentation on driving roundabouts
that was played for all the students at both schools.
Construction Management
The project was awarded on May 16, 2006 with 530 working days. The completion date
was scheduled for the fall of 2008. The project was substantially completed on
December 29, 2007 with the final lanes opened to traffic. At that time the project had
over 176 working days (8 months) remaining on the project. Considerable acceleration
of the project had to do with the construction of the roundabout.
During the summer of 2007, the contractor and the city worked together to develop a plan
to close the intersection of 164th Avenue SE and SE 256th Street for two weeks. The
primary reason that this was allowed was to address how the roundabout would be
constructed since the final grade of the roundabout would be 18 inches lower than the
existing grade. The lowering of the intersection was necessary in order to maintain an
acceptable uniform grade for the operational safety of the roundabout. In addition there
were existing concrete panels that needed to be removed and the roadway built back up.
This would result in the existing roadway being excavated three feet. Therefore, the
intersection was allowed to be closed for two weeks during the hours of 7 AM and 4 PM
each day. This allowed the entire roundabout to be constructed in those two weeks
including final paving. This allowed the roundabout to be operational when school
started in the fall of 2007 and avoided several months of traffic control phases as well as
temporary signal configurations to construct the roundabout. The closure received very
few complaints since it was publicized via press releases and door hangers/flyers were
placed in all the neighborhoods in the area.
In general, the contractor made considerable efforts to schedule work to minimize
disruptions to the traveling public. In addition, school traffic was closely coordinated
between the city, Kent School District and R. W. Scott Construction to minimize impacts
to bus schedules and student/parent access. A representative of the Kent School District
was invited to attend the weekly construction meetings to provide on-site coordination of
any school related issues. The school district representative attended on a regular basis
which helped in discussions and coordination of project impacts. Access to the two
schools was well maintained for the project duration with only minimal delays.
The project also came in under budget. The awarded bid was over 10.4 million dollars
for the entire project. The actual cost of the project is under 10 million dollars. Although
the project did have several unforeseen items that resulted in additional work, the overall
construction management of the project, in the end, proved to be a large cost savings.
This included closely monitoring quantities with regularly projected project completion
costs that allowed the City to make decisions on expanding the scope to enhance and/or
fix areas that were just outside the project limits. For example, the grinding and paving
limits on the project were expanded to improve an intersection just outside the project
limits that had several patches that were in need of repair. Another example was
expanding the landscaping of the planter strips to blend and improve the landscaping of
some of the older neighborhood planter strips that were just outside the project limits.
The city, contractor and consultant worked closely throughout the project to identify,
review and implement possible cost savings opportunities, such as the temporary closure
of the intersection to construct major components of the roundabout. This closure
resulted in a significant cost savings to the City and allowed work to be completed by the
contractor with fewer disruptions and increased efficiency.
These were just a couple examples of the many that were accomplished with knowing
where the project was in terms of budget throughout the construction.
Safety
The safety performance of the project was exemplary. There were not any lost time
injuries during the entire project with a recorded 36,000 work hours during construction.
The contractor had a safety program and conducted regular safety meetings with their
employees in accordance with their safety plan. The contractor also had certified flaggers
as part of their staff versus many contractors that hire a subcontractor to do that work.
The city on numerous occasions received compliments from citizens as to their
courteousness as well as their professionalism is dealing with traffic.
In addition the project did not experience any known pedestrian or vehicle accidents
during the entire construction project. There was much of concern that the construction of
a double lane roundabout (or any roundabout) would result in unsafe conditions for
motorists and pedestrians, especially students. Since the project has opened we have
received only positive responses from citizens and school officials as to how the
roundabout functions.
Environmental
Due to the size of the project there were several areas of concern that needed to be
protected. These areas included wetlands, potential wetlands, tributaries and seasonal
drainage courses. To aid in protecting these resources, the city obtained from the
Department of Ecology a “Construction Stormwater General Permit” prior to the project
going out for bid. Within the permit there were several requirements and reports that
would be needed to demonstrate that the project would be in compliance.
It was determined that the most effective way to ensure that the project was in
compliance was to transfer the responsibility to the contractor. Therefore, the City put
the requirements into the project specifications with the intent that the permit would be
the responsibility of the contractor with the city monitoring results.
Once the project was awarded, the contractor had an employee obtain the necessary
training to become a Certified Erosion and Sediment Control Lead (CESCL) as required
by the Department of Ecology. In addition to the implementation of the Stormwater
Pollution Prevention Plan (SWPPP) that included temporary erosion and sediment control
measures for the entire project, the contractor conducted weekly samples of their
stormwater discharges. These samples were tested using a turbidity meter and recorded
on a form that was submitted monthly to the Department of Ecology. None of the results
of the turbidity tests exceeded the allowable benchmark.
Community Relations
Ongoing public outreach about the project was provided by the city through a variety of
methods such as a series of articles published in the Covington Reporter monthly updates,
public meetings, information on the website, distributing informational flyers to all the
students at the schools in the area, and issuing joint press releases with the Kent School
District. The culmination of these efforts resulted in over twenty separate pieces of
information.
In addition, city staff gave presentations on separate occasions on driving around the
roundabout to the Kent School District Transportation Department and the Parent
Teacher Student Association (PTSA). City staff was also video taped explaining how to
drive roundabouts and that information was played for all the Kentwood High School
students by the Kent School District. The city received many thanks for all their
educational and informational efforts.
As mentioned earlier, during the two week closure of the intersection there were press
releases notifying the public of the closure as well as flyers and door hangers placed in all
the neighborhoods in the area. This was well received from the citizens because they
understood the need for the closure and they knew the impact early enough to adjust their
trips accordingly.
The project website was in place during both the design and construction phases of the
project. During construction, updates were posted to advise of project status, schedule,
upcoming traffic impacts, temporary utility disruption as well as other general project
information. The website also provided information regarding the multiple project
partners and offered web viewers the opportunity to provided comments on the project.
The Kent School district also worked with the City to pick up students at a local church
outside the construction area to reduce the amount of vehicle and pedestrian traffic going
through the work zone. This was just another example of the collective effort to make
the project a success.
Unusual Accomplishments
One of the issues with the construction site being in the middle of two schools was the
impact to walking students. There was a lot of concern that during the construction of the
project there would be no safe routes for students to walk to school. The City agreed to
place temporary pedestrian fencing to designate where students should walk and placed
surfacing as necessary to accommodate pedestrians.
In addition the staging of some of the construction did not allow for pedestrians to cross
at the crosswalks to get to the schools. In order to get students safely to the schools
without crossing the arterial uncontrolled, the contractor placed flaggers in areas to
accommodate students needing to cross the road. The Contractor was very responsive to
any additional pedestrian needs that arose during the course of the project work and
scheduled their work accordingly.
These practices reduced the concerns of the parents in facilitating the needs of the
walking students and helped enforce the positive relationship between the citizens, Kent
School District and city.
Another challenge that arose during construction had to do with the main storm drainage
trunk line that needed to tie into an existing regional storm water detention pond that was
sized to service the roadway expansion. Over the years, houses were constructed in the
vicinity of the drainage easement and grading occurred that made the installation of the
trunk line within that easement virtually impossible without serious impacts to
homeowners.
The city, consultant and contractor talked about options to installing the storm drainage
trunk line in the existing easement and the impacts to the residents as well as the
constructability of the plan. It was decided to acquire additional easement area on the
property adjacent to the existing easement that was undeveloped (except for one house).
The city negotiated with the property owner a price for the easement which allowed for a
constructible installation with minimal impacts to the residents at an overall lower price.
Additional Considerations
There was much concern during the design of the project on how to construct the
roundabout and facilitate traffic. Prior to the construction project, the intersection at
164th Avenue SE and SE 256th Street was controlled by a traffic signal. In order to
facilitate the existing geometrics of the roadway and take into account a family grocery
store that has been in business since 1927, the intersection (roundabout) had to be shifted
north and lowered 18 inches.
Therefore the plans reflected temporary signals being installed as the different phases of
the roundabout were constructed. During the actual construction of the project, it was
observed that traffic had dropped to avoid the intersection because motorists were
diverting to other routes in the area. These observations prompted the city, consultant
and contractor to evaluate other possibilities in phasing how the roundabout would be
constructed. With the changes of the traffic patterns it was observed that traffic was
balanced coming from all directions and that a 4-way stop could function well and
alleviate the need of temporary signals being installed and reinstalled for the different
phases.
However, these observations were made during the summer and traffic would
significantly increase once school was back in session. The contractor proposed closing
the intersection for two weeks and completely reconstructing the roadway and building
the roundabout. The closure was allowed for the two weeks on the premise that the
roundabout would be open prior to school being back in session in the fall. We placed
the signal in 4-way flash while work was being done in the area and witnessed that the
traffic actually did function well as expected. The peak hours functioned well so the
contractor was allowed to remove the signal and place 4-way stop signs and begin
prepping for the roundabout.
The intersection was then closed for two weeks in August of 2007. At the end of the two
weeks the roundabout was fully constructed and paved (including final lift) prior to
school starting in the first week of September. This willingness to “go against the norm”
saved over a $100,000 in costs to the project and saved months of impacts to motorists
and pedestrians.
There were many keys to success in the construction of this project. However, the
common factor seemed to come back to the approach taken by the city, consultant and
contractor. As issues arose all parties kept an open mind and were willing to consider all
ideas and reach the best solution for all stakeholders (motorists, pedestrians, partners,
city, consultant, contractor, etc.). The focus was always having a quality end product.
This is a rarity to have all parties involved working well together which in the end created
a project that was appreciated by all.
Contact
Don Vondran, PE
City Engineer
253-638-1110