Better Data, Better Flood Risk Management
The Harris County Modeling, Assessment and Awareness Project (MAAPnext) will develop the next generation of flood mapping. Along with new Flood Insurance Rate Maps (FIRMs), new tools will be developed for communicating the results of this project. Changes are on the way for Harris County flood maps, and we are ready to bring the region’s flood resistance and resilience to the next level.
MAAPNEXT DATA ADVANCEMENTS
This assessment will incorporate updated rainfall depth, duration, and frequency data from the National Oceanic and Atmospheric Administration’s (NOAA) recently released Atlas 14, Volume 11 Precipitation-Frequency Atlas of the United States, Texas, and updated terrain data developed in 2018.
Updated rainfall and terrain data
Helps us create better analysis tools
This updated information will be used to create and run a more comprehensive type of analysis and hydrologic and hydraulic modeling (H&H) modeling, which is heavily data dependent.
MAAPNEXT TECHNOLOGY ADVANCEMENTS
Recent advancements in hydrologic and hydraulic modeling software and methodologies will allow the Flood Control District to identify and evaluate flood risks to a greater degree of accuracy and detail than was previously possible. These advancements will allow HCFCD to understand and map flooding related to bayous, creeks and other natural drainage patterns. Additionally, urban flooding, flood risk due to rainfall run-off draining through streets and neighborhoods on the way to the bayous, will also be assessed.
New modeling software and methodologies
Enhance the accuracy of our flood risk analysis
The resulting data will produce a variety of flood mapping products that will allow Harris County to better understand flooding risks to support their decisions in the future.
MAAPNEXT APPROACH
MAAPnext will incorporate different types of flooding—including riverine, urban, and coastal flooding—into the modeling to analyze and depict our flood risks in Harris County in a way that was not technologically feasible before. This new, more comprehensive type of analysis and hydrology and hydraulics modeling is heavily data dependent, and we have not previously had the technological capability to map our flood risks in this way.
Assessment
USE NEW DATA AND TOOLS
Updated rainfall depth, duration, and frequency data from the National Oceanic and Atmospheric Administration’s (NOAA) recently released Atlas 14, Volume 11 Precipitation-Frequency Atlas of the United States, Texas.
Updated terrain data was obtained in 2018 and provide the foundation of hydraulics models and maps.
Up-to-date versions of the Hydrologic Modeling System and River Analysis System software products developed by the Hydrologic Engineering Center of the U.S. Army Corps Engineers now allows for feasibile countywide 1D/2D analysis.
Updated permeability data based on 2018 aerial imagery.
Completed flood damage reduction projects will also be incorporated.
Products
DATA-DRIVEN DELIVERABLES
MAAPnext results, including new hydrologic and hydraulic models, Flood Insurance Rate Maps, and other flood risk products developed by the Flood Control District and its team of consultants will be delivered to FEMA for review by the end of 2021.
Public Review
RESULTS
Once reviewed by FEMA, preliminary data will be made available for public review and comment before they become effective.
Impacts
PROTECTION FOR THE FUTURE
Many changes to existing mapped floodplains are expected. It is anticipated that this updated information will impact how future projects, new development, and associated flood mitigation strategies are planned and implemented throughout Harris County.