water quality modeling workshop hworkshop, h … water quality modeling workshop hworkshop, h-gac...

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Water Quality Modeling Water Quality Modeling Workshop HWorkshop H--GACGACWorkshop, HWorkshop, H--GACGACOverview of Specific ModelsOverview of Specific Models

Tina Petersen, P.E., Ph.D.Tina Petersen, P.E., Ph.D.

June 30, 2010June 30, 2010

Presentation OutlinePresentation Outline

Background and IntroductionBackground and Introduction– Impairments in H-GAC Region

– Considerations for TMDL Model Selection

Overview of Specific Models– Watershed Models

– River Models

– Estuary/Bay Models

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Typical WQ Impairments in HTypical WQ Impairments in H--GAC GAC RegionRegion

Bacteria: 60% ofBacteria: ~60% of stream milesDO: 20% of stream milesOther concerns:– Nutrients– Dioxins/PCBs– Toxic sediments

From 2008 303(d) ListFrom 2008 303(d) List

Modeling Needs for Modeling Needs for TMDL developmentTMDL development

Loading from sourcesN i t ( b d b )– Nonpoint sources (urban and non-urban)

– Point sources

Determination of TMDL, waste load and load allocationsIn-stream assimilation of loading from sourcessourcesImpact and effectiveness of control strategiesFuture conditions (population, land use changes)

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Water Quality ModelsWater Quality Models

WASPWASPRIVMODRIVMOD

AGNPSAGNPS CECE--QUALQUAL--ICMICM

HSPFHSPFBATHTUBBATHTUB

LSPCLSPC QUALTXQUALTX

QUAL2KQUAL2K

SWMMSWMM

SWATSWATWAMWAM

BLESTBLEST

LDCLDC

GWLFGWLF SLAMMSLAMM

SWATSWAT

SELECTSELECT

EFDCEFDCWAMWAM

WARMFWARMF

Tidal Prism/Box ModelTidal Prism/Box Model

LDCsLDCs

Model Selection ConsiderationsModel Selection Considerations

Maturity of Models for TMDLs/WPPsType of modelParameters of interestCost

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Water Water QualtiyQualtiy Models Applied in Texas Models Applied in Texas & H& H--GAC Region for TMDLs/WPPsGAC Region for TMDLs/WPPs

ArcHydro QUALQUAL--TXTXArcHydroSELECT BLEST HSPF SWAT

QUALQUAL TX TX RMA2 RMA2 TPM TPM EFDC EFDC

WASP

Bacteria Task Force (BTF)Bacteria Task Force (BTF)

Convened in SeptemberConvened in September 2006Goals of task force:

Examine models used in other states

Recommend cost effective d ti ffi i t th dand time efficient methods

for TMDL development

Evaluate models and BST methods and recommend when methods are appropriate

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Recommended models by Bacteria Recommended models by Bacteria Task ForceTask Force

Model Bacteria Task ForceTier 1 Tier 2 Tier 3Tier 1 Tier 2 Tier 3

LDCs

ArcHydro

SELECT

SPARROW

BIT

BLESTBLEST

HSPF

SWAT

SWMM

WASP

Models for Detailed DiscussionModels for Detailed DiscussionModel Used in TX

WPP/TMDLsIn H-GAC Region BTF

Recommended

LDCs

ArcHydro

Model Applied in TX WPP/TMDLs

Applied In H-GAC Region

BTF Recommended

LDCs

ArcHydro

SELECT

SPARROW

BIT

BLEST

HSPF

SWAT

SWMM

SELECT

SPARROW

BIT

BLEST

HSPF

SWAT

SWMMSWMM

WASP

QUAL-TX/QUAL-2K

TPM

EFDC

SWMM

WASP

QUAL-TX/ QUAL-2KTPM/TBM

EFDC

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Categories of Tools Categories of Tools for TMDL/WPP for TMDL/WPP DevelopmentDevelopment

Watershed Models

River

Lake/ Estuary Models

ModelsLDCsLDCs Spatially Spatially

Explicit/ Explicit/ Mass Mass

BalanceBalance

WatershedWatershed

Rivers, Rivers, BayousBayous

Lakes,Lakes,ReservoirsReservoirs

From Ward & From Ward & BenamanBenaman, 1999, 1999

Estuary, BayEstuary, Bay

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WatershedWatershed– BLEST

– SELECT





WatershedWatershed– HSPF

– SWAT



– SWMM



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WatershedWatershed



– QUAL-TX/ QUAL-2K



WatershedWatershed



– WASP

– EFDC



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WatershedWatershed





– Tidal Prism/ Tidal Box Model

WatershedWatershed



– WASP

– SWAT

– HSPF

QUAL TX



– QUAL-TX, QUAL-2K

– EFDC

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Simulated ParametersSimulated Parameters

Model DO Nutrients Sediment Toxics Bacteria Temp

LDCs

SELECT

BLEST

HSPF

SWAT

SWMM

WASPWASP

QUAL-TX/QUAL-2K

Tidal Prism/Box ModelEFDC

Cost Cost –– Model TypeModel Type

ComplexityComplexity

LDCsLDCs Spatially Spatially ExplicitExplicit

Models/Mass Models/Mass BalanceBalance

WatershedWatershedModelsModels

River/StreamRiver/StreamModelsModels

Estuary Estuary ModelsModels

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Other ConsiderationsOther Considerations

Input data and calibration requirementsInput data and calibration requirementsAvailability of existing modelsSuitability to resolve key questions

Model OverviewModel Overview

LDCs River ModelsRiver ModelsSpatially Explicit/ Mass Balance

BLEST

SELECT

Watershed/River Models

River ModelsRiver ModelsWASPWASPQUALQUAL--TX/QUALTX/QUAL--2K2K

Tidal ModelsTidal ModelsTidal Tidal PrismPrism

HSPF

SWAT

SWMM

EFDCEFDC

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BLEST

SELECT




HSPF

SWAT

SWMM

EFDCEFDC

Load Duration Curves (LDCs)Load Duration Curves (LDCs)

From From Buffalo and Whiteoak Bayou TMDL for Fecal PathogensBuffalo and Whiteoak Bayou TMDL for Fecal Pathogens

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Load Duration Curves (LDCs)Load Duration Curves (LDCs)Benefits • Simple to apply (if data are available)

• Based on actual water quality dataChallenges • No insight into specific sources or their loadsChallenges • No insight into specific sources or their loads

• No spatial information regarding sources• Limited ability to use findings for BMP selection

Model suitability • Screening tool• Non-tidal streams• Flow is primary driver of WQ patterns• When sources are clear or anticipate WQ impairment during one particular flow regimeduring one particular flow regime• Conservative parameters (metals, sediment) or bacteria

Modeling needs for TMDLs/WPP addressed

• General sources of bacteria (point, nonpoint source, mixture)• Determination of TMDL, WLA, LA

Cost to run • Low



BLEST

SELECT




HSPF

SWAT

SWMM

EFDCEFDC

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BLESTBLEST

From From Buffalo and Whiteoak Bayou TMDL for Fecal PathogensBuffalo and Whiteoak Bayou TMDL for Fecal Pathogens

SELECTSELECT

From From Plum Creek Watershed Protection PlanPlum Creek Watershed Protection Plan

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Spatially Explicit/Mass Balance ModelsSpatially Explicit/Mass Balance Models

Benefits • Moderately simple to apply (if data are available)• Based on literature values (or known data if available)

Challenges • Spatial information regarding sources is lumped by watershed (BLEST only)• Steady state/inventory• No in-stream assimilation of bacteria loads

Model suitability • Watershed inventory of sources• Watersheds where multiple sources of bacteria are active• Bacteria impairments only• Bacteria impairments only


• Watershed loading from bacteria sources• General spatial questions about bacteria loading.• Control strategy impact on watershed pollutant loads

Cost to run • Low to Moderate



BLEST

SELECT




HSPFSWATSWMM

EFDCEFDC

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HSPFHSPF

From HSPF User’s ManualFrom HSPF User’s Manual

SWATSWAT

From From SWAT User’s ManualSWAT User’s Manual

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SWMMSWMM

SSSS

R R f(t)f(t)

I I f(t)f(t)

SS

Q (t)Q (t)

From From Plum Creek Watershed Protection PlanPlum Creek Watershed Protection Plan

Watershed/River ModelsWatershed/River ModelsBenefits • Continuous results allow \evaluation of multiple

conditions in the watershed• Build-up wash-off simulations provide detailed and d f ibl i t l didefensible nonpoint source loading

Challenges • Require large amounts of data to set up and calibrate• Require time and expertise to set up and operate model• Lumped parameter

Model suitability • In-stream dynamics for non-tidal streams only• Multiple water quality parameters• Urban or agricultural environment


• Watershed loading from pollutant sources• Determination of TMDL, WLA, LA• In-stream assimilation of pollutant loading• Control strategy and future condition impact on watershed loads and in-stream pollutant concentrations

Costs to run • Moderate to High

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BLEST

SELECT




HSPF

SWAT

SWMM

EFDCEFDC

WASPWASP

Model Preprocessor/Data ServerModel Preprocessor/Data ServerModel Input File (Binary)Model Input File (Binary)

WASPWASPInputInput

BMDBMDEUTROEUTRO

StoredStoredDataData

Hydro Hydro

Binary Model OutputBinary Model OutputModelsModelsHydrodynamicHydrodynamicInterfaceInterface

TOXITOXI

MOVEMMOVEMMercuryMercury

Graphical Post ProcessorGraphical Post ProcessorFrom US EPA Presentation on WASPFrom US EPA Presentation on WASP

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QUALQUAL--TX/QUALTX/QUAL--2K2K

Screen Shot from QUAL2KScreen Shot from QUAL2K

River ModelsRiver ModelsBenefits • Detailed in-stream routing and dynamics

• Detailed eutrophication modelsChallenges • Require large amounts of data to set up and calibrateg q g p

• Require time and expertise to set up and operate model• May require external hydrodynamic or sediment transport models for tidal or 2D/3D applications• Require input from watershed model for runoff loads

Model suitability

• Tidal (WASP only) and non-tidal streams• Multiple water quality parameters• Urban or agricultural environment


•Determination of TMDL, WLA, LA• In-stream assimilation of pollutant loading• In-stream changes that occur as result of watershed future conditions and control strategy implementation


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BLEST

SELECT



Tidal ModelsTidal ModelsTidal PrismTidal Prism

HSPF

SWAT

SWMM

EFDCEFDC

Tidal Tidal Prism/ Tidal Box Prism/ Tidal Box ModelModel

DieDie--off/Lossesoff/Losses

Tidal Tidal ExchangeExchange

Tidal Tidal ExchangeExchange SegmentSegment

Watershed RunoffWatershed Runoff(From HSPF)(From HSPF)

Point SourcePoint SourceLoadingLoading

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EFDCEFDC

From From EFDC User’s ManualEFDC User’s Manual

Estuary ModelsEstuary ModelsBenefits • Simulate tidal fluctuations and impact on water quality

• Sediment digenesis and wetland simulation (for EFDC)• Set up can be completed in MS Excel (Tidal Prism)

Challenges • Require large amounts of data to set up and calibrate• Require time and expertise to set up and operate model• Require input from watershed model for runoff loads• Execution times exceed 12+ hours (for EFDC)

Model suitability

• Tidal conditions (EFDC can also simulate non-tidal)• Multiple water quality parameters• Urban or agricultural environmentg


•Determination of TMDL, WLA, LA• In-stream assimilation of pollutant loading• In-stream changes that occur as result of watershed future conditions and control strategy implementation


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Discussion and QuestionsDiscussion and Questions

water quality modeling workshop hworkshop, h … water quality modeling workshop hworkshop, h-gac...

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