NWS Flood Forecast Mapping Application FLDVIEW NOAA NWS Office of

NWS Flood Forecast Mapping Application FLDVIEW NOAA/NWS/Office of Hydrologic Development Hydrology Laboratory Janice M. Sylvestre WMO/NOAA Hydrologic Forecasting Course NWS Training Center Kansas City, MO October 27, 2003

Hydraulic Modeling Components FLDWAV: NWS Hydraulic Routing Model Stand-Alone (R&D Application) Operation within NWSRFS FLDAT: FLDWAV Analysis Tool Generates input deck for FLDWAV Displays and analyzes FLDWAV results FLDVIEW: Flood Forecast Mapping Application Displays the extent of flooding FLDIMS: Flood Internet Mapping Service View flood maps in addition to other layers over the Internet

FLDVIEW Objectives § Generate a flood forecast map based on NWS probabilistic river forecast § Visually display flood forecast map and other geographical and structural layers

FLDVIEW - Benefit Flood forecast mapping improves the public’s understanding of river forecasts by representing the extent of flooding along a river reach in a nontechnical way.

Operational Priorities q Stable - Runs under any condition q Fast - Runs in a reasonable amount of time (minutes vs. hours) q Accurate - Gives reasonable results q Robust - Runs with limited data q Easy to use - As many steps as possible are automated q Independent – Map application not dependent on any particular hydraulic model

FLDVIEW Data Requirements Contour Lines (DEM) Man-Made Structures Centerline Water Surface Profile (hydraulic data) 0 1500 feet

Water Surface Profiles Types of water surface profiles Deterministic - Peak elevations along the channel reach - Instantaneous elevations at a given time along the channel reach Probabilistic - Elevations along the channel having the same probability of occurrence Source of profiles - NWS dynamic routing models (DWOPER/FLDWAV) - Routing methods in NWSRFS (e. g. , Muskingum-Cunge) - Simplified techniques (e. g. , slope method, backwater, etc. )

Flood Map Generation 1. Process DEM data 2. Add channel bottom and man-made structures 3. Generate ground grid 4. Generate channel widths at water surface along the river 5. Generate water surface grid 6. Generate depth grid (water surface grid – ground grid) 7. Generate the flood map

FLDVIEW Features q Maps both drought and flood conditions q Considers structures (dams, bridges, levees) q Flood map may be generated with limited data q Processes Auto. CAD and USGS data automatically q Multiple maps may be generated automatically q Multiple rivers may be mapped

FLDVIEW Applications Rio Panaco – Tampico, Mexico Lewistown, PA Rio Choluteca Tegucigalpa, Honduras Missouri River – St. Charles, PA

FLDVIEW Applications Susquehanna River System (MARFC) – Lewistown, PA lower West Branch, PA St. Johns River – Fredericton, New Brunswick Canada Tar River – NC (SERFC) St. Johns River – FL (SERFC)

FLDVIEW – Current NWS Implementation National Weather Service River Forecasting System Hydrologic data Routing FLDWAV Model Flood Forecast map Water Surface Profile Ascii Text File FLDVIEW Geographic data Grid or Vector Inundation map Probabilistic or Deterministic

FLDVIEW Input Files. xy file 1 . fcs file Number of map scenarios 1984 Name of flood forecast map 1 48. 4 -77. 599 40. 577 447. 99 48. 4 475. 5223 1692. 8296 -999 1 47. 625 0 0 445. 91 47. 625 473. 3482 1574. 3484 -999 1 46. 85 0 0 443. 83 46. 85 470. 442 1392. 6216 -999 1 46. 84 0 0 443. 83 46. 84 470. 3957 1388. 8903 -999 1 46. 5 0 0 443. 83 46. 5 469. 0605 10884. 0742 -999 1 46. 2467 0 0 442. 9417 46. 2467 468. 1956 9105. 6992 -999 1 45. 9933 0 0 442. 0533 45. 9933 467. 4252 7542. 4292 -999 1 45. 74 0 0 441. 165 45. 74 466. 7634 6171. 0713 -999 1 45. 4867 0 0 440. 2766 45. 4867 466. 199 4956. 2461 -999 1 45. 2333 0 0 439. 3883 45. 2333 465. 7229 3867. 4519 -999 1 44. 98 -77. 5558 40. 5798 438. 5 44. 98 465. 323 2877. 6511 -999 0 44. 4538 0 0 437. 2308 44. 4538 464. 5272 938. 4684 -999 0 43. 9277 0 0 435. 9615 43. 9277 463. 7095 916. 4625 -999 0 43. 4015 0 0 434. 6923 43. 4015 462. 8641 893. 1454 -999 0 42. 8754 0 0 433. 4231 42. 8754 461. 9841 868. 4618 -999 0 42. 3492 0 0 432. 1538 42. 3492 461. 0663 842. 4289 -999 Map River Mile Latitude Longitude Thalweg River Mile WSEL Top width WSEL (town)

FLDVIEW Specifications q System Hardware HP Unix workstation Windows 95/98/2000/Me/NT/XP q System Software Arcview 3. 1+ Spatial Analyst 3 -D Analyst

FLDVIEW Future Research q Assess quality of results § Accuracy: compare against orthophotos of floods § Sensitivity: use different DEM sources q Improve method to map water surface in floodplain q Improve statistics for probabilistic water surface profile q Investigate other methods for obtaining water surface profile

NWS Flood Internet Mapping Service (Prototype) FLDIMS

FLDIMS Description q Map. Guide web application q Displays FLDVIEW results without the need for the user to purchase expensive software q Client-side driven

FLDIMS Application 140. 90. 22. 51

FLDIMS Features q Probabilistic flood forecast maps q Deterministic peak flood forecast map q Display other layers q Historical flood maps q Flood animation q Identify information in flooded area

FLDIMS Future Work q Apply to another area to evaluate the adaptability of the template for use by the RFC in generating FLDIMS applications for different areas