Technical expertise and independent insight for complex groundwater challenges.
MMA works with professionals and organizations who need reliable answers to difficult groundwater questions.
Independent analysis, expert opinions, model review, and testimony.
Water supply, groundwater management, permitting, planning, and technical review.
Advanced modeling, peer review, and specialized hydrogeologic expertise.
Water supply, permitting, contaminant investigations, and groundwater impact evaluations.
Founded in 1990 by Michael McDonald and Daniel Morrissey following distinguished careers with the U.S. Geological Survey, MMA has deep roots in groundwater science and numerical modeling. As a co-developer of the original MODFLOW code, Mike McDonald helped establish the foundation for what has become the world’s most widely used groundwater modeling software. That legacy continues to shape MMA’s commitment to technical excellence, scientific rigor, and high-quality groundwater consulting.
McDonald Morrissey Associates has been solving complex groundwater problems since 1990. Nationally recognized for the analysis of groundwater flow systems, MMA combines decades of specialized experience with sophisticated quantitative modeling and practical, independent technical guidance.
More than three decades of specialized groundwater consulting.
Mike McDonald, co-founder of MMA, developed MODFLOW, the world’s most widely used groundwater modeling code.
Complex groundwater projects for industrial, legal and government clients throughout the United States and internationally.
MMA combines hydrogeologic expertise with quantitative modeling to help clients understand groundwater systems and make technically sound decisions.
Modeling and analysis for water supply, resource management, permitting, and groundwater/surface-water interactions.
Fate-and-transport analysis and modeling to understand contaminant movement, impacts, and remediation.
Independent technical opinions, model review, expert reports, testimony, and litigation support.
Groundwater modeling and analysis for mine dewatering, extraction, impacts, and regulatory considerations.
Groundwater modeling for landfills, wastewater systems, Superfund sites, and other complex applications.
MMA has completed complex groundwater projects throughout the United States and internationally.
Water-management and interstate water-resource issues.
Addressing mine pumping and potential surface-water impacts.
Evaluating contaminant sources and the influence of municipal pumping.
