Dr. Richard N. Palmer, Margaret A. Hahn, Dr. Azad Mohamadi, Dennis Kessler, Joe Dvorak

Department of Civil and Environmental EngineeringUniversity of Washingtonpalmer@u.washington.edu

http://maximus.ce.washington.edu/~palmer/

A Computer Assisted Decision Support System

Portland Water Bureau’s Storage and Transmission Model (STM)

Endangered Species

Growing Urban Demands

Climate Variability

Planning Process Drivers for IMP

Stakeholder Interest Wholesale contract renewal (2005) Water shortage Governance Issues

(Wilsonville Tigard) Clackamas Consortium to evaluate

transmission Reliability/Vulnerability

Potential Role from “Strategic Direction and Mission”

Be the regional water supplier

Supply Multnomah Counties and

others as water is available

Serve primarily Portland

Serve the historic service base

IMP Objectives

Provide cost data for contracts Examine emergency supplies Address aging infrastructure Develop evaluation procedures Identify preferred alternatives

During the past 50 years, our means of water resource evaluation has changed remarkably

The Evaluation of Supply Alternatives

Qua

lity

of L

ife

Years

Portland System

Serves ~ 840,000 people Largest system in state Bull Run

Watershed (215 MGD capacity)

Columbia South Shore Wellfield 1984 (90 MGD capacity)

Bull Run Watershed national forest

reserve in 1892

First pipeline built in 1895, 24 miles

long.

Dam 1 built in 1929

Conduit 4 built to 100 mgd

Dam 2 built in 1962

Bull Run System

Dam 1

Dam 2

Bull Run Lake

Modeling Approach

Who will use the model, how will it be used?

Facilitate evaluation of a wide range of alternatives

Reflect issues of importance to the degree possible

Shared Vision of resources, operations and alternatives

Modeling Approach

Requires modeling environment that is flexible and robust

Built conjunctively with Bureau PWB must understand strengths

and limitations of model Ownership must be shared by

PWB and model developers

Questions to be addressed

What is the safe yield? What is yield of Dam 3? What is the yield of groundwater? What are the impacts of operations? Is transmission adequate? Should in-town storage be increased? In what year is increased supply

required?

Primary Alternatives

Conservation Expansion of In-Town Storage

and Transmission Groundwater Dams ASR Changing of Operating Rules

Portfolio of Alternatives

EXISTING

Conservation Groundwater Dam 3Expansion

WEST

EAST

REGIONAL EXISTING,

DAM 3, MEDIUMCONSERVATION

EXISTING,

HIGHCONSERVATION

EXISTING, MEDIUM

CONSERVATION

REGIONAL, DAM3, HIGH

CONSERVATION

Software Selection

What the model does

Tracks daily movement of water Evaluates future water

demands In 30 seconds:

evaluates 500,000 variables for any year from 1940-1998 for any forecasted period for 60

years

Key Metrics

Adequacy of Supply

Storage Remaining

Groundwater Used, ratio of use

Percent Reliability

Transmission Shortfall

First decision support tools

Notice attention to detail!

Notice stakeholder involvement and

outreach program in action

Now, lets see, which button was I supposed

to push for the paper feed?

PWB Team

Scenario Process

Two iterations were used Describe plausible futures with

emphasis on different goals Develop 20 scenarios, evaluate, then

further investigate 9 Bring together staff members to view

impacts of scenarios with the STM Note surprises, counter-intuitive results,

and insights

Lessons learned

Conservation will play an important role Conduit 5, Powell Butte Reservoirs I&II,

Upgrade CSSW, Treatment, Westside ASR Use of groundwater drives Dam 3 Dam 3 could supply regional customers If no expansions in BR, then groundwater More customers with new surface sources

requires increased groundwater use

Future Activities

Automate STM Develop a Bureau systems

approach to modeling Integrate models where

appropriate Explore role of climate change

(climate variability)

Identify Problems and Objectives

FormulateTeams

Define the Status Quo

FormulateAlternatives

EvaluateAlternatives

Implementthe Plan

Exercisethe Plan