cuahsi fall 2004 vision paper cyberseminar series · pdf fileflood team: jean bahr-uwisc...

CUAHSI Fall 2004 Vision Paper Cyberseminar Series

www.cuahsi.org

CUAHSI Fall 2004 Vision Paper Cyberseminar Series

www.cuahsi.org

Leal Leal MertesMertesComing to you from Coming to you from Santa Barbara, CASanta Barbara, CAOctober 5October 5thth, 2004, 2004To begin at 3:05 ETTo begin at 3:05 ET

FloodplainsFloodplains

Welcome to the 3Welcome to the 3rdrd Semester of Semester of CUAHSI CUAHSI

Education and Outreach Education and Outreach Distinguished LecturesDistinguished Lectures

Host: Jon DuncanHost: Jon DuncanCUAHSI Communications CUAHSI Communications

Director

Problems? Send a chat to Host

Feedback? Please send an email to [email protected]

Director

The Presentation can be downloadedFrom www.cuahsi.org

Fall ScheduleFall ScheduleScaling and Hydrologic ModelingScaling and Hydrologic Modeling--

Geoff Geoff ThyneThyne, CSM. October 14, CSM. October 14thth

Intensively Managed LandscapesIntensively Managed LandscapesBill Simpkins, ISU. October 19Bill Simpkins, ISU. October 19thth

EcohydrologyEcohydrology of Semiof Semi--Arid EnvironmentsArid EnvironmentsBrent Newman, LANL. October 21Brent Newman, LANL. October 21stst

Go to CUAHSI website for complete calendar, links Go to CUAHSI website for complete calendar, links to papers, presentations, and discussion forumsto papers, presentations, and discussion forums

FLOODPLAINSCUAHSI Cyberseminar:

October 5, 2004Noon – Pacific Time

Leal A.K. MertesDepartment of Geography

UCSB

[email protected]

FLOOD TEAM:Jean Bahr - UWiscMartin Doyle - UNCLeal Mertes - UCSB

Andrew Miller - UMarylandGeoff Poole - UGAKen Potter - UWisc

Jim Smith - PrincetonRip Sparks - UIllinoisEmily Stanley - UWisc

Landsat

OUTLINEOUTLINE1st Principles– Scale– Geomorphology– Hydroclimatology– Habitat

Human ImpactResearch Agenda– Flood Discharge

Urban Watersheds – Flood Frequency– Inundation Hydrology

Water Distribution – Floodplain Capacity & ModellingPerirheic Mixing - SedimentHyporheic Exchange – Thermal

– Geomorphic Template – Heterogeneity & Landscape Arrangement– Biogeochemistry – Nitrogen Cycle– Biology – Flow Reversals

Summary – Societal Importance– Enoughness?– Function Compression

11stst PRINCIPLES PRINCIPLES -- Spatial Scale:Spatial Scale:Riverine Geomorphology & EcologyRiverine Geomorphology & Ecology

Watershed101 km2-106 km2

Valley/Reach100 m-104 m

Channel Unit100 m-103 m

Stream Bed100 cm-105 cm

(Poff, 1997)

11stst PRINCIPLES PRINCIPLES –– Hydroclimatology:Hydroclimatology:Spatial & Temporal ScalesSpatial & Temporal Scales

(after Hirschboeck, 1988)

Watershed101 km2-106 km2

Valley/Reach100 m-104 m

Channel Unit100 m-103 m

Stream Bed100 cm-105 cm

11stst PRINCIPLES PRINCIPLES -- Flood Flood Hydroclimatology & BiomesHydroclimatology & Biomes

(hydroclimatology after Hayden, 1988 - as published in Poff et al. 2001)

HUMAN IMPACT HUMAN IMPACT -- DamsDams

100 200 3000

Duration

Reversal

Rate ofrise

Rate of fall

Day of the yearIndicators of Hydrologic Alteration (IHA, Richter et al. 1996): 42 biologically meaningful hydrologic parameters for eight gage sites along the Illinois River.

“Ideal” (1887)

HUMAN IMPACT –Geomorphic simplification of floodplains –

Willamette River and floodplain

1854 1910 1967

(Sedell and Froggatt, 1984)

RESEARCH AGENDARESEARCH AGENDA– Flood Discharge

Urban Watersheds – Flood Frequency– Inundation Hydrology

Water Distribution – Floodplain Capacity & Modelling

Perirheic Mixing - SedimentHyporheic Exchange – Thermal

– Geomorphic Template – Heterogeneity & Landscape Arrangement

– Biogeochemistry – Nitrogen Cycle– Biology – Flow Reversals

FLOOD DISCHARGE FLOOD DISCHARGE --QuestionsQuestions

What is the relationship between the channel – floodplain system and the history of storm events in an urban drainage basin?What are the dynamic processes associated with flooding at the watershed scale, how do floods respond to the interplay between hydrometerology, geology, topography, and anthropogenically modified features of the landscape?

FLOOD DISCHARGE FLOOD DISCHARGE --AssertionsAssertions

Floods are both spatially and temporally complex and notoriously difficult to measureStage/discharge relationships are not necessarily single-valued; can get looped or hysteretic rating curves when following rising and falling limbs of the same eventCan get substantial lateral water-surface gradients across the floodplain with changing stage during a floodCan also get backwater effects, sometimes including reverse flow at confluences and constrictions; or associated with transient obstructions like debris jams

FLOOD DISCHARGE – Urban WatershedsExtreme conditions in small watersheds

FLOOD DISCHARGE – Urban WatershedsUrban channel/floodplain systems are not necessarily simple; channels and riparian zones may exhibit strongly heterogeneous characteristics over short distances.

Flood of June 13, 2003

0

500

1000

1500

2000

2500

3000

3500

4000

4500

5000

6/13/03 15:00 6/13/03 17:00 6/13/03 19:00 6/13/03 21:00 6/13/03 23:00 6/14/03 1:00 6/14/03 3:00 6/14/03 5:00

Dis

char

ge in

ft3/

s

Whitemarsh Run at FullertonWhitemarsh Run at White Marsh

(Whitemarsh in Baltimore region watershed)

The Urban Hydrologic SystemThe Urban Hydrologic System(courtesy of Ken Belt, U.S. Forest Service)(courtesy of Ken Belt, U.S. Forest Service)

Water Supply Pipes

WastewaterConduits

Stormdrains

GroundwaterFlow Paths

Septic Systems

Impervious Surfaces

Artificial Channels

INUNDATION HYDROLOGY INUNDATION HYDROLOGY --Watershed Structure &Watershed Structure & the the

Floodplain PatchFloodplain Patch

Variable contributions from sourcescan produce differentinundation patterns.

SOURCES of WATERIN = main channel input

TR = major tributaryL = local tributary

GW = groundwater/hyporheic waterP = local precipitation

INUNDATION HYDROLOGY INUNDATION HYDROLOGY --Floodplain Capacity: Distribution Floodplain Capacity: Distribution

of Floodplain Waterof Floodplain WaterHow much water in a stream ever resides on the floodplain?What is the frequency distribution of inundation depths and areas?What is the frequency distribution of residence times of water that reaches floodplain surfaces?How is this residence time distributed across a watershed?

INUNDATION HYDROLOGYINUNDATION HYDROLOGY-- Distribution Distribution of recurrence intervals as a measure of capacity of recurrence intervals as a measure of capacity

for river reaches (for river reaches (WoltemadeWoltemade 1993)1993)

INUNDATION HYDROLOGY -

ModellingFloodplain

Flows

INUNDATION HYDROLOGY - GW & HW Model Results

for Flathead River

radius = degree of variationin GW vector over 6-month simulation

direction & magnitude of GW flow vectorupwelling (white) & downwelling(black); radius = vertical flux

INUNDATION HYDROLOGY INUNDATION HYDROLOGY --Surface Water Mixing: PerirheicSurface Water Mixing: Perirheic

INUNDATION HYDROLOGY INUNDATION HYDROLOGY --Surface Mixing: Monitoring SedimentSurface Mixing: Monitoring Sediment

R. Negro + R. Solimões = Amazonas

Landsat 321 = RGB August 15, 1988

INUNDATION HYDROLOGY INUNDATION HYDROLOGY --Perirheic Mixing on Amazon FloodplainPerirheic Mixing on Amazon Floodplain

~2 km

perirheos

INUNDATION HYDROLOGY INUNDATION HYDROLOGY --SubSub--Surface Water Mixing: HyporheicSurface Water Mixing: Hyporheic

Channel

Riparian Zone

HyporheicPhreatic

Streambed Paleochannel

AlluvialAquifer

INUNDATION HYDROLOGY –Hyporheic Exchange: Thermal Monitoring

Temperature patterns from data loggers (Arrigoni 2004)

°°

°

20

21

22

23

24

25

26

27

28

1 3 5 7 9 11 13 15 17 19 21 23Time (hours)

Mea

n te

mpe

ratu

re (

C) a

cros

s sa

mpl

ing

per

iod

river (downwelling)

ground water (upwelling)

°

upwelling

downwelling

INUNDATION HYDROLOGY –Hyporheic Exchange: Thermal Monitoring

Fine Temporal Monitoring with Field Instruments(Arrigoni 2004)

15

17

19

21

23

25

27

29

31

20-Jul 22-Jul 24-Jul 26-Jul 28-Jul 30-Jul 1-Aug 3-Aug 5-Aug 7-Aug 9-Aug 11-Aug 13-Aug

Wat

er T

empe

ratu

re (°

C)

Downwelling Predicted

Upwelling Predicted

Rain

INUNDATION HYDROLOGY –Thermal Monitoring with Forward-Looking Infrared Radiometer (FLIR)(Torgersen et al. 2001 as published in Mertes et al. 2004)

GEOMORPHIC TEMPLATEGEOMORPHIC TEMPLATE

GEOMORPHIC TEMPLATE – Fine resolution data –LiDAR - Upper Gwynns Falls

GEOMORPHIC TEMPLATE –Measuring Heterogeneity, i.e.

Landform VariabilityJökulhlaup on Skeiðarársandur, Iceland

November 5-7, 1996 (Guðmundsson & Sigurðsson, 1996)



Iceberg Landforms

(Guðmundsson & Sigurðsson, 1996)



Channel Landforms

(Iceland Calendar 1997)


Landform VariabilitySandur Variability Map Based on Digital Elevation

Map from Airborne Radar Altimetry (Smith et al. 2000)

(J. Mason)

GEOMORPHIC TEMPLATE GEOMORPHIC TEMPLATE ––Human Impact: Mesopotamian MarshesHuman Impact: Mesopotamian Marshes

Changing the TemplateChanging the Template

Mesopotamia

GEOMORPHIC TEMPLATE GEOMORPHIC TEMPLATE ––Landscape Landscape Re Re –– ArrangementArrangement

Mesopotamian Mesopotamian MarshlandsMarshlands

From 1970s to present, marshlands re-engineered and drained. White areas on 3 images (Landsat – 77 & MODIS – 02 & 04) show location of open water during “flood” season. Grey tones show wetland vegetation. Renewed water releases due to 2003-2004 Iraqi conflict show impact of drainage engineering on geomorphic template &, therefore, inundation pattern.

BIOGEOCHEMISTRY – Nitrogen Cycle

(Figure courtesy of Bruce Peterson)

BIOGEOCHEMISTRY – Nitrogen Cycle: Watershed Scale

(Seitzinger et al. 2001)

BIOGEOCHEMISTRY – Nitrogen Cycle Nitrate transport and transformation in

groundwater beneath floodplains

How can floodplain preservation and restoration contribute to reducing nitrogen export from agricultural lands?What combinations of subsurface hydrostratigraphy, surface topography, vegetation, and inundation patterns create conditions that promote subsurface denitrification?What field monitoring strategies are necessary for and most effective at identifying zones of denitrification and quantifying denitrification rates in the subsurface?

BIOGEOCHEMISTRY – Nitrogen CycleBasic requirements for denitrificationa) Microbial population of denitrifiersb) Suitable Redox conditions (low Dissolved Oxygen - DO)c) Electron donor (organic carbon or other reduced species)

Floodplain zones in which these conditions are expected include shallow wetland soils and zones of hyporheic exchange

Hyporheic Zone

Shallow wetland soils

Transient water levels may create deeper mixing zone in which organic carbon moved downward with infiltrating water serves as electron donor for reduction of nitrate from upland agricultural areas.

Can floodplain complexity generate additional zones of denitrification?

Local topography creates complex flow paths

BIOGEOCHEMISTRY –Nitrogen Cycle

BIOGEOCHEMISTRY – Nitrogen CycleGreater potential for denitrification in groundwater beneath floodplains with complex topography and frequent inundation compared to those with more uniform topography and steady water levels or flowpaths

RESEARCH STRATEGY– Comparative studies in floodplains with

varying degrees of physical and hydrologic complexity and affected to varying degrees by human or other disturbance

– Integration of stratigraphic, hydrologic, geochemical, vegetation and microbiologic data

– Monitoring over sufficient time to characterize effects of variations in flow paths and nitrogen sources at seasonal and inter-annual scales.

BIOGEOCHEMISTRY – Scale Issues

?Need for understanding

nutrient dynamics at the scale of the problem

-Characteristic small-scale variation of floodplains

-Small-scale of measurement

versus

# of

sam

ples

DEA (ng N/g soil/hr)0 5 10 15 20 25 30 40 50 75 100150

0

25

50

75

100

Denitrification 19990 25 50 75 100 125 150

Den

itrifi

catio

n 20

00

0

50

100

150

200

250

300

BIOLOGYBIOLOGY

BIOLOGY – Human Impact: Flow reversals

100 200 3000

Moist soil plant growing season

Spikes

Duration

Reversal

Rate ofrise

Rate of fall

Day of the year

Effects on Plants

0 100 200 300Day of Year

130

132

134

136

Riv

er L

evel

(met

ers

abov

e m

sl)

Pre-dam (1887)

Post-dam (1987)

natural dryseason

From Technical support of public decisions to restore floodplain ecosystems:a status report on the Illinois River project, 2000


Altered Water Regime

Biomass

Plant height

g

End of growing season

With pre-dam (1887) hydrograph


g

Biomass

Plant height

End of growing season

With post-dam (1987) hydrograph

BIOLOGY BIOLOGY –– Human Impact: Flow reversals

SUMMARY SUMMARY –– Societal ImportanceSocietal Importance

– Enoughness?– Function Compression

Societal Importance: Societal Importance: Striking a BalanceStriking a Balance

Natural Goods & Services

Natural Goods & Services

Engineered System Services

Engineered System Services

Drinking WaterNutrient Retention

FisheriesFlood MitigationWildlife Habitat

TransportationHydropowerAgricultureRecreation

SUMMARY – Societal ImportanceThe value of nature and the nature of value.

“Identify the production functions” (Daily et al.)

N removal/uptakeFlood reductionProduction of fish, wildlifeMaintenance of biodiversity“Serenity”

“Enoughness” questions – How much (e.g., in-stream flow)?

Arrangement on landscape – Upstream-downstream; lateral

SUMMARY – Societal Importance

“Function Compression”Doing more with less -- Providing equivalent ecosystem services on

smaller area.

(Firth, Galat, Sparks -- Water Environment Research Foundation (WERF) Workshop)

cuahsi fall 2004 vision paper cyberseminar series · pdf fileflood team: jean bahr-uwisc...

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