Creating a Flood Warning System for the San Diego River

Watershed

Martin J. Teal, P.E., P.H., D.WREWEST Consultants inc.

Darren BertrandWEST Consultants Inc.

Rand AllenSan Diego County

OUTLINE

• San Diego River Watershed

• HEC-RTS Overview

• San Diego River models created for HEC-RTS

• San Diego River HEC-RTS

• Questions/Discussion

WATERSHED LOCATION

www.sandiegoriver.org

SAN DIEGO RIVER WATERSHED

“SAN DIEGO PRECIPITATION

ATMOSPHERIC RIVERS

Qualcomm Stadium in Mission Valley during the 2010 Flooding Eventhttp://www.dailymail.co.uk/

River Ridge Golf Course in Mission Valley during the 2010 Flooding Eventhttp://www.dailymail.co.uk/

Mission Center Road in Mission Valley during the 2010 Flooding Eventhttp://www.dailymail.co.uk/

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

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)

METEROLOGIC MODEL (MFP)• The Metrologic 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)

• Manual forecasted precipitation can also be input (e.g. No Future Rainfall)

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

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

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

HYDRAULIC MODEL (HEC-RAS)• HEC-RAS will

compute water surface profiles and stage hydrographs along with inundation boundaries and depth maps

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

WATERSHED SETUP

DATA AQUISITION

DATA VISUALIZATION

MODEL INTERFACE

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

IMPLEMENATATION AND NEXT STEPS

• Floodplain Mapping static maps for quick reference

• Set up of system and data links on County workstation

• Development of a user manual

• Customized on-site training for County staff

• Fully Operational in late fall of 2015

QUESTIONS?