Creating a Flood Forecasting System for the San Diego River Watershed

Transcription

1 Creating a Flood Forecasting System for the San Diego River Watershed Rand Allan County of San Diego Flood Control Martin J. Teal, P.E., P.H., D.WRE WEST Consultants inc.

2 OUTLINE San Diego River Watershed HEC-RTS Overview San Diego River models created for HEC-RTS San Diego River HEC-RTS Questions/Discussion

3 WATERSHED LOCATION

4 SAN DIEGO RIVER WATERSHED

5 SAN DIEGO PRECIPITATION

6 ATMOSPHERIC RIVERS (Pineapple Express)

7 ATMOSPHERIC RIVERS January 3-7 Jet Stream

8 Qualcomm Stadium in Mission Valley during the 2010 Flooding Event

9 River Ridge Golf Course in Mission Valley during the 2010 Flooding Event

10 Mission Center Road in Mission Valley during the 2010 Flooding Event

11

12 HEC-RTS OVERVIEW HEC-RTS is the Hydrologic Engineering Center s Real-Time Simulation program HEC-RTS is a publically avaliable version of the Corps Water Managment System (CWMS) that runs on a single computer without using an Oracle database or a UNIX Server

13 HEC-RTS OVERVIEW HEC-RTS provides support for decision making using any combination of the following models: Meteorology (MFP) Hydrology (HEC-HMS) Reservoir operations (HEC-ResSim) River hydraulics (HEC-RAS) Flood impact/economic analysis (HEC-FIA)

14 METEROLOGIC MODEL (MFP) The Meteorologic Forecast Processor (MFP) combines observed precipitation with future precipitation scenarios The San Diego River HEC-RTS model creates gridded rainfall datasets from 26 point precipitation gages located throughout the watershed and combines these with future rainfall derived from the National Weather Service QPFs (Quantitative Precipitation Forecasts) Manually forecasted precipitation can also be input (e.g. No Future Rainfall)

15 HYDROLOGY MODEL (HEC-HMS) Rainfall runoff calculations are computed using the hydrologic modeling software HEC-HMS The watershed was divided into 49 subbasins Constant-Deficit Loss Method Gridded ModClark Transformation Method Muskingum Routing Method Recession Baseflow Method

16 HYDROLOGY MODEL (HEC-HMS) Two calibration events and one validation event were used to develop a single set of parameters to be used in the HEC-RTS hydrology model (Dec 2004, Dec 2010, Feb 2011) Three USGS stream flow gages as well as computed inflow into the San Vicente and El Capitan Reservoirs were used for the calibration process San Diego River Fashion Valley gage 2010 Event San Diego River Santee Gage 2004 Event

17 HYDRAULIC MODEL (HEC-RAS) River Hydraulics are computed with hydraulic modeling software HEC-RAS Hydrographs produced by the HEC-HMS hydrology model are used as inflow boundary conditions in the unsteady HEC- RAS model The unsteady RAS model for the San Diego River covers over 75 miles of river reach has over 60 culverts/bridges and 3 reservoirs with inline structures The entire main reach of the San Diego River along with San Vicente, Boulder, Forester and Los Coches tributaries are modeled

18 HEC-RAS will compute water surface profiles and stage hydrographs along with inundation boundaries and depth maps HYDRAULIC MODEL (HEC-RAS)

19 HEC-RTS MODULES The Control and Visualization Interface (CAVI) is the primary framework of RTS and controls the other functional modules. Watershed Setup Module Data Acquisition Module Data Visualization Module Model Interface Module

20 WATERSHED SETUP

21 DATA ACQUISITION

22 DATA VISUALIZATION

23 MODEL INTERFACE

24 ADDITIONAL HEC-RTS FEATURES The use of custom scripts and a script editor allows the user to create custom features in HEC-RTS such as: Auto Schedule Data collection processing Auto schedule forecast simulations to be run an a daily basis Automatic report generation and posting from user specified locations

25 IMPLEMENTATION AND NEXT STEPS Website to host static floodplain maps for quick reference Set up of system and data links on County workstation Implementation of threshold warnings at select locations and texting to emergency managers Development of a user manual Customized on-site training for County staff

26 QUESTIONS?