Roads and Sewers - Cahaba River Society


Cahaba River Society supports sustainable growth that is socially, environmentally, and economically responsible. We specialize in education and collaboration to advocate for water-protective development and revitalization. We have directly participated in many cost-effective development solutions now on the ground and have given awards to 80 firms and agencies for water-protective development and restoration projects.

Click below to learn more about Specific Transportation Projects in the Cahaba Watershed and to read Cahaba River Society’s position statements on them:


Cahaba Beach Road Expansion



Birmingham Northern Beltline

Cahaba River Society Science Committee Report, Purpose, and Conclusions

Towards these goals, the Cahaba River Society Board requested that the Cahaba River Society Science Committee conduct an objective, in-depth evaluation of the science and methodology underpinning the “Final Environmental Impact Statement Reevaluation” (FEISR) for the BNB. That review is available at Scientific Review of the “Final Environmental Impact Statement Reevaluation”.

Regretfully, the Scientific Review found that the FEISR is not based on sound, current science and methodology, leading to significant erroneous conclusions. The FEISR is seriously inadequate in projecting impacts of the BNB and the growth it generates on water pollution, drinking water, federally protected species and their critical habitats, and wetlands.

There were two significant shortcomings of the BNB FIESR that deserve particular emphasis. Firstly, the impact of the most significant source of the most important pollutant to the Cahaba River, post-construction sediment loading, was not evaluated or properly modelled. The FEISR concluded that Total Suspended Solids (TSS or sediment) loading to the Cahaba River watershed would actually diminish from baseline conditions as a result of all five potential building scenarios they modelled. That conclusion is very much at odds with changes to sediment loading in streams documented in scientific literature.

Secondly, potential impacts of post-construction changes to water supply and pollution, and thus on the cost, quality, and availability of drinking water was ignored by the FEISR. Since the Cahaba River is an irreplaceable element of the drinking water supply for Birmingham, such an oversight by the FEISR must be addressed.

Thus the FEISR does not provide an adequate scientific basis for decision-making about the project and for consideration of alternatives and actions that could avoid, reduce and mitigate impacts. It does not provide justification for the lack of a Supplemental Environmental Impact Statement (SEIS), which CRS believes is necessary for the eastern end of the BNB (from I-65 to I-59).

Review and Uses of the Report

We value the communication that CRS and ALDOT have developed and appreciate ALDOT’s leadership in inviting and supporting this process. CRS and ALDOT have collaborated in educational training regarding improved highway design to conserve water resources, and ALDOT has allowed CRS to serve as a resource providing initial comments for improving the water-protective design of the first section of the Northern Beltline.

ALDOT has requested that the US Army Corps of Engineers (USACE) proceed with the permit for the first section of the BNB. CRS is releasing the Scientific Review to organizations, agencies, and interested citizens, for consideration of this significant information as they comment on the permit. It is our intention that the Scientific Review will guide improved studies for the BNB to further joint understanding of the potential impacts of this important project and how to best address them.

Cahaba River Society is committed to continuing our conversation and collaborative work with ALDOT, to ensure that best practices in planning, design and construction will be used for all ALDOT projects, to protect the Cahaba River and our region’s drinking water and waterways.