Successful USACE Section 203 studies require more than leadership—they demand a multidisciplinary team with nationwide experience. Our broader bench includes specialists in planning, engineering, environmental compliance, economics, and stakeholder engagement who have supported feasibility studies across the country. Together, they bring the depth, technical rigor, and regional insight needed to advance sponsor-led studies efficiently, meet USACE expectations, and move projects from concept to authorization. These highlighted team members are just a sample of our broader team.
Gretchen Brown
Senior Project Manager, Water Resources
Five years as a civil works project manager at USACE, Galveston District, managing feasibility studies in shallow and deep draft navigation, shoreline stabilization, and flood risk management. Experience includes Section 203 studies for the Raymondville Drain Study (flood risk management) and Cedar Port Channel (deep draft navigation), as well as one year at HDR managing the SAFER 203 Study, a flood risk management effort spanning 11 watersheds in Harris County, Texas.
Colleen Roberts, P.E.
Water Business Development Lead
Eleven years supporting USACE feasibility and mega studies, including major river and levee systems and complex, nationwide flood risk and watershed programs. Representative projects: Little Blue River (MO); Manhattan Levee Improvements (KS); Shunganunga Creek (KS); Missouri River Bed Degradation Study; Lower Missouri River Navigation Study; Jefferson City, MO L-142 Flood Risk Management Feasibility Study.
Ryan Hammons, PWS
Senior Wetlands Specialist
(702) 435-4975 | Ryan.Hammons [at] hdrinc.com (Ryan[dot]Hammons[at]hdrinc[dot]com)
Section 203 Environmental Lead Specializing in Permitting Strategy and Risk Reduction for USACE Approval
Ryan is a senior wetland specialist and certified Professional Wetland Scientist with experience supporting USACE Section 203 studies through environmental planning, permitting strategy, and regulatory coordination. He specializes in Section 404 permitting, Section 7 consultation, and Migratory Bird Treaty Act compliance, key to developing permit-ready deliverables. Ryan supports water, federal, energy, and transportation clients, aligning environmental documentation with USACE expectations. He also contributes to ecosystem restoration and holds an FAA Remote Pilot Certificate for sUAS data collection.