Straughan is providing Emergency Action Plan (EAP) development services for Prince George’s County, Maryland’s significant and high hazard dams. These services require detailed administrative documentation, extensive coordination with County and State Agencies, and comprehensive dam breach analyses. Straughan’s success in facilitating agreement among County Agencies regarding EAP roles and responsibilities and in preparing revised EAPs demonstrates our proficiency in supporting the Department of Environment in additional and increasingly complex tasks associated with the EAP revision process.
As a part of this project, Straughan performed hydrology, hydraulics, and dam breach analysis for five significant and high hazard pond/lake embankments. The goal of dam safety is to model the impacts of both dam maintenance and dam failure under a selected set of conditions. The depth and velocity hydraulics of the conditions are then compared to determine whether the breach increases the danger based on the two hydraulic properties. An increase in danger required us to determine the population-at-risk (PAR), including the traveling public, structures, and unprotected persons. Straughan used several modeling methods to determine the hydraulics for the dam breach analysis. Our development of breach and no breach scenario flows allowed Prince George’s County to evaluate the downstream flood hazards through inundation mapping and calculating population-at-risk, providing confidence in dam hazard classification.