1. Bridging the Gap in Bridge Construction Impacts
Ecological Assessment from Design through Construction
I’m from the south, so I’m not sure I made the right choice to give a lightning talk, but I’ll do my best to talk fast. I would like to talk to y’all about what can be the hidden impacts of bridge construction. This is actually a story about how GDOT was not properly assessing impacts and it is probably the appropriate time to tell you that I’m actually the co-Ecology Section Manager at GDOT, so since he’s not here, I’ll say that it was my colleague’s fault but I’ve been diligently working to create a process where we fully assess bridge construction impacts. To get you in the right frame of mind, the picture on this slide shows a rock jetty within critical habitat for a number of federally protected mussels that was nearly not assessed.
Chris Goodson, Ecology Section Manager
Georgia Department of Transportation – Office of Environmental Services

2. Background
Construction plan sheets historically have only shown permanent bridge structures from which impacts to resources are assessed.
The true impacts of any construction project are potentially difficult to quantify. Permanent impacts are typically shown on construction plan sheets. But, what about the associated temporary impacts needed for construction access? This presentation aims to detail how GDOT collaborated between offices to get a little closer to quantifying the true impacts associated with bridge construction.
However, methods for construction, including access within environmentally sensitive areas (e.g. streams, wetlands, etc.), are often left up to the contractor unless access limitations are defined.

3. Construction Access Types
In our defense, GDOT Ecologists would always ask the bridge designer how a bridge would be built over large waterways and was always told that a barge would be used. That was seemingly great from an ecological standpoint because it minimized impacts, so we didn’t ask any further questions. Unfortunately, a barge was not always the actual construction method. It turns out, the people who actually know how a bridge is built work in Construction. This all began about four years ago during a project that was under construction when a GDOT Construction Liaison asked if we had permitted for the work bridge that was going to be used. Thus begins our journey.
Barge
Floating work platform used for bridge construction access, which is held in place with driven piles

4. Construction Access Types
Work Bridge
Bulkhead
It turns out that bridge contractors use a variety of methods to access areas during bridge construction. Once we actually took the time to think about it, it seems clear that a barge can’t be used where water levels are low or fluctuate significantly. A work bridge with driven piles can’t be used when bedrock is too close to the surface. And jetties can have potentially significant impacts to ecological resources such as fish, mussels, snails and the water resources themselves.
Coffer Dam
Jetty

5. Developing Discussion Venues
In addition to pre-existing meetings that brought together environmental, design and construction staff, GDOT created “Constructability Meetings” to specifically discuss construction access needs early in the plan development process.
Each bit of new information regarding the actual bridge construction process brought more questions and complicated our agency consultation and permitting processes. To ensure that construction access impacts on future projects were accurately assessed, GDOT developed Constructability Meetings to bring together environmental staff with bridge designers and construction. This gave construction staff a venue during pre-construction to communicate anticipated access needs while allowing environmental staff to truly address avoidance and minimization measures and properly assess ecological impacts. When the constructability discussion concluded, the designer was the bridge to illustrate the permitted access to the contractor through a special plan sheet.

6. Communicating Permitted Access
Existing Bridge Removal
Proposed Substructure Construction
Proposed Superstructure Construction
This plan sheet illustrates the permitted access required, which GDOT uses to complete environmental consultation. Access will be needed for construction of the proposed bridge substructure and superstructure, as well as removal of the existing bridge once the proposed bridge is complete and traffic has shifted [Mouse click]. The area shown in blue represents the space needed for a crane arm to pivot freely across the length of the bridge to install the large beams that ultimately reduce ecological impact. [Mouse click]

7. Why Assess Constructability?
Accounts for construction needs during pre-construction
Determines right-of-way & easement limits
Minimizes design re-work
Secures necessary environmental permits
Prevents delays during project construction
Discussion Milestones:
So hopefully it is clear why these construction access impacts should be assessed from an environmental consultation and permitting standpoint but just as important are the relationships that you develop between offices that may not naturally communicate well. While GDOT experienced some growing pains and a lot of initial pushback from design and construction, the GDOT Office of Environmental Services now holds monthly roundtables with Bridge Design to discuss project-specific issues, as well as other current topics that include retrofitting bridges to accommodate bats and ensuring bridges accommodate wildlife passage.

8. Discussion Milestones:
Lessons Learned
Engage construction and design personnel early on in the plan development process
Assess the potential impacts that temporary construction access may have on environmental resources and complete all agency consultation and permitting
Implement a process for communicating permitted access areas to contractors
Discussion Milestones:
But to get back to the original topic, it’s important to engage construction and design personnel early during pre-construction to capture the greatest opportunity for avoidance and minimization of impacts to environmental resources. Formalizing this process through a stand alone meeting and specialized plans can ensure that construction access is consistently assessed and permitted.

9. Chris Goodson – cgoodson@dot.ga.gov GDOT Ecology Section Manager
Questions?
If there are any DOTs out there that are not currently addressing construction access when assessing environmental impacts, I hope this presentation has been helpful for you and I would be happy to chat with you after this session or you can me. For those DOTs that have been assessing these temporary construction impacts for the past many years, and I hope that’s all of you, I would also love to chat with you after this session to see if we can improve our process. Thanks for listening.
Chris Goodson –
GDOT Ecology Section Manager