Nuisance Flood Plan
Nuisance Flood Plan Phase I: Tidal Nuisance Flood
The purpose of Phase 1 of the Prince George’s County Nuisance Flood Plan is to identify areas within the County prone to high-tide flooding, assess the impacts, provide options for tracking the effects of high-tide flooding over time, and identify recommended actions.
Various terms have been used to define high tide flooding. These include sunny-day, nuisance, recurrent, tidal, and sea level rise flooding (NOAA, 2020a). While there is no nationally recognized definition of high tide flooding, for purposes of this plan, high tide flooding refers to when local sea level temporarily rises above an identified threshold height for flooding, in the absence of storm surge or riverine flooding (U.S. Federal Government, 2020), to the point where it causes a public inconvenience. It should be noted that the term nuisance flooding is sometimes also used to describe flooding that is a result of clogged or overflowing storm drain systems that are outside of the floodplain and occurs during minor storm events. The term nuisance flooding as used in this plan is limited to high tide flooding.
High tide flooding in the absence of storm surge or riverine flooding may not pose as serious a threat to Prince George’s County or result in major damages to public and private properties, but it can interrupt the daily routines of residents in the County’s coastal areas. Locations subject to high tide flooding may eventually be vulnerable to more severe floods due to sea level rise, land subsidence, and the loss of natural barriers (NOAA, 2020a). This plan will enable the County to determine the extent of high tide flooding, create a baseline inventory for the years 2019 through 2021, and be used to evaluate contributing conditions.
Nuisance Flood Plan Phase II – Urban Nuisance Flooding
Prince George’s County’s first Nuisance Flood Plan (2020) was in response to Natural Resource Article §3-1001 of the Maryland Annotated Code which required local jurisdictions that experienced nuisance flooding to develop a plan to address it. As written, Maryland code defines nuisance flooding as tidal-driven flooding, or “high tide flooding that causes a public inconvenience.” In Prince George's County, high-tide flooding is a risk to the low-lying areas along the tidal reaches of the Potomac River and the Patuxent River. While these areas are increasingly vulnerable to higher high tides due to sea level rise, and the loss of natural barriers, tidal impacted areas form only a small percentage of the County’s flood risk areas. Stormwater driven urban flooding occurs throughout the County and especially in low lying basin areas and areas that receive significant surface runoff. These areas tend to be more numerous and more widespread in the County than those impacted by high tide. To cover both these types of flooding under one Nuisance Flood Plan, the definition of nuisance flooding was expanded to cover both urban flooding and high tide flooding, and a Nuisance Flood Plan- Phase 2 was developed in 2023.
The updated plan identifies areas within the County prone to urban flooding using collected flood data from County and federal agencies. The plan in addition to identifying such areas, assesses the impacts, refines options for tracking the effects over time, and identifies potential actions to address urban flood impacts. It builds upon and expands the analysis prepared for Phase 1 to identify, track, and improve our understanding of both high-tide and urban flooding to create a more actionable nuisance flood plan. The Nuisance Flood Plan- Phase 2 report provides detailed information on the methodology employed to develop the study and contains maps of impacted areas based on the data received. The study also developed an ArcGIS Story Map that explains the issue and impact of urban flooding in a graphical and interactive environment. Both the report and the Story Map can be accessed via the links provided below.
Phase 2: Urban and Tidal-driven Nuisance Flooding
Tackling Nuisance Flooding in Prince George’s County