aridlandsinstitute · in river basins. flood risk, water supply, and water quality are affected by...

intro and thank yous

A R I D L A N D S I N S T I T U T E@ Woodbury University

aridlands.org

A R I D L A N D S I N S T I T U T E @Woodbury University 7500 Glenoaks Blvd | Burbank CA | 91510 aridlands.org


Sandy 2012: Windspeed Analysis, Indian Space Research Organization OceanSat-2;Katrina 2005: Windspeed Analysis, NASA JPL QuikSCAT satellite.

Design has a powerful role to play in climate adaptation.


responding to change:

RebuildByDesign.org

RebuildByDesign.org Resiliency Proposal for NYC: BIG U, BIG Team, 2014

anticipating change:

Divining LA: Drylands City Design for the Next 100 Years


The challenges:

1. WATER IN THE WEST IS CHANGING.


www.sciencemag.org SCIENCE VOL 319 1 FEBRUARY 2008 573

POLICYFORUM

Systems for management of waterthroughout the developed world havebeen designed and operated under the

assumption of stationarity. Stationarity—theidea that natural systems fluctuate within anunchanging envelope of variability—is afoundational concept that permeates trainingand practice in water-resource engineering. Itimplies that any variable (e.g., annual stream-flow or annual flood peak) has a time-invari-ant (or 1-year–periodic) probability densityfunction (pdf), whose properties can be esti-mated from the instrument record. Under sta-tionarity, pdf estimation errors are acknowl-edged, but have been assumed to be reducibleby additional observations, more efficientestimators, or regional or paleohydrologicdata. The pdfs, in turn, are used to evaluateand manage risks to water supplies, water-works, and floodplains; annual global invest-ment in water infrastructure exceedsU.S.$500 billion (1).

The stationarity assumption has longbeen compromised by human disturbancesin river basins. Flood risk, water supply, andwater quality are affected by water infra-structure, channel modifications, drainageworks, and land-cover and land-use change.Two other (sometimes indistinguishable)challenges to stationarity have been exter-nally forced, natural climate changes andlow-frequency, internal variability (e.g., theAtlantic multidecadal oscillation) enhancedby the slow dynamics of the oceans and icesheets (2, 3). Planners have tools to adjusttheir analyses for known human distur-bances within river basins, and justifiably ornot, they generally have considered naturalchange and variability to be sufficientlysmall to allow stationarity-based design.

In view of the magnitude and ubiquity ofthe hydroclimatic change apparently nowunder way, however, we assert that stationarityis dead and should no longer serve as a central,default assumption in water-resource riskassessment and planning. Finding a suitablesuccessor is crucial for human adaptation tochanging climate.

How did stationarity die? Stationarity isdead because substantial anthropogenicchange of Earth’s climate is altering themeans and extremes of precipitation, evapo-transpiration, and rates of discharge of rivers(4, 5) (see figure, above). Warming aug-ments atmospheric humidity and watertransport. This increases precipitation, andpossibly flood risk, where prevailing atmo-spheric water-vapor fluxes converge (6).Rising sea level induces gradually height-ened risk of contamination of coastal fresh-water supplies. Glacial meltwater temporar-ily enhances water availability, but glacierand snow-pack losses diminish natural sea-sonal and interannual storage (7).

Anthropogenic climate warming appearsto be driving a poleward expansion of thesubtropical dry zone (8), thereby reducingrunoff in some regions. Together, circulatoryand thermodynamic responses largelyexplain the picture of regional gainers andlosers of sustainable freshwater availability

that has emerged from climate models (seefigure, p. 574).

Why now? That anthropogenic climatechange affects the water cycle (9) and watersupply (10) is not a new finding. Nevertheless,sensible objections to discarding stationarityhave been raised. For a time, hydroclimate hadnot demonstrably exited the envelope of natu-ral variability and/or the effective range ofoptimally operated infrastructure (11, 12).Accounting for the substantial uncertaintiesof climatic parameters estimated from shortrecords (13) effectively hedged against smallclimate changes. Additionally, climate projec-tions were not considered credible (12, 14).

Recent developments have led us to theopinion that the time has come to movebeyond the wait-and-see approach. Pro-jections of runoff changes are bolstered by therecently demonstrated retrodictive skill of cli-mate models. The global pattern of observedannual streamflow trends is unlikely to havearisen from unforced variability and is consis-tent with modeled response to climate forcing(15). Paleohydrologic studies suggest thatsmall changes in mean climate might producelarge changes in extremes (16), althoughattempts to detect a recent change in globalflood frequency have been equivocal (17,18). Projected changes in runoff during themultidecade lifetime of major water infra-structure projects begun now are largeenough to push hydroclimate beyond therange of historical behaviors (19). Someregions have little infrastructure to buffer theimpacts of change.

Stationarity cannot be revived. Even withaggressive mitigation, continued warming isvery likely, given the residence time ofatmospheric CO2 and the thermal inertia ofthe Earth system (4, 20).

A successor. We need to find ways toidentify nonstationary probabilistic modelsof relevant environmental variables and touse those models to optimize water systems.The challenge is daunting. Patterns ofchange are complex; uncertainties are large;and the knowledge base changes rapidly.

Under the rational planning frameworkadvanced by the Harvard Water Program(21, 22), the assumption of stationarity was

Climate change undermines a basic assumptionthat historically has facilitated management ofwater supplies, demands, and risks.

Stationarity Is Dead:Whither Water Management?P. C. D. Milly,1* Julio Betancourt,2 Malin Falkenmark,3 Robert M. Hirsch,4 Zbigniew W.Kundzewicz,5 Dennis P. Lettenmaier,6 Ronald J. Stouffer7

CLIMATE CHANGE

1U.S. Geological Survey (USGS), c/o National Oceanic andAtmospheric Administration (NOAA) Geophysical FluidDynamics Laboratory, Princeton, NJ 08540, USA. 2USGS,Tucson, AZ 85745, USA. 3Stockholm International WaterInstitute, SE 11151 Stockholm, Sweden. 4USGS, Reston,VA 20192, USA. 5Research Centre for Agriculture andForest Environment, Polish Academy of Sciences, Poznan,Poland, and Potsdam Institute for Climate ImpactResearch, Potsdam, Germany. 6University of Washington,Seattle, WA 98195, USA. 7NOAA Geophysical FluidDynamics Laboratory, Princeton, NJ 08540, USA.

*Author for correspondence. E-mail: [email protected].

An uncertain future challenges water planners.


Milly, P.C.D., Betancourt, J., Falkenmark, M., Hirsch, R., Kundzewicz, Z., Lettenmaier, D., and Stouffer, R., Stationarity Is Dead: Whither Water Management?, Science, 1 February 2008: 319 (5863), 573-574.

The response:

DESIGN FOR VARIABILITY.


The challenges:

2. WATER IN THE WEST IS ENERGY-and CARBON-INTENSIVE.


The response:

UNCOUPLE THE WATER-ENERGY NEXUS.


The challenges:

3. POLICY BARRIERS SEPARATEWATER QUALITY vs. WATER SUPPLY


Quality:

Federal Water Pollution Control Act (1948)

Clean Water Act (1972 - 2002) 33 U.S.C. §1251 et seq. (1972)


Los Angeles County Flood Control District, Design Manual-Hydraulic, Los Angeles, March 1982.

Supply:

CA Superior Court: City of LA vs. City of San Fernando, et al. (1962), (1979)

City of LA Granted Pueblo Rights | Safe Yield REQUIRES Imported Supplies


Supply:

Los Angeles County Flood Control District, Hydraulic Design Manual, 1982

Stormwater as Threat

Los Angeles County Flood Control District, Design Manual-Hydraulic, Los Angeles, March 1982.A R I D L A N D S I N S T I T U T E @Woodbury University 7500 Glenoaks Blvd | Burbank CA | 91510 aridlands.org

Quality:

California Regional Water Quality Control Board,

Municipal Stormwater and Wastewater Discharge Requirements , Dec. 2012.


The response:

INTEGRATE WATER QUALITY and SUPPLY POLICY.


The opportunity:

Los Angeles as test-bed.The case for localization.


Maximizing use, reuse, and recovery of rain and stormwater resources is central to establishing a robust localized water portfolio.



MWD Blue Ribbon Committee:“By maximizing use and recovery of rain and stormwater resources while improving water use efficiency and recycling, up to 82% of water demand can be met through the strategic use and reuse of a broad-scale local water resource portfolio.”

An Integrated Response

Drylands Resilience InitiativeComprised of:

Hazel : An Integrated Environmental Modeling Tool;DRI Network: A Multi-Sector Research Collaborative;Divining LA: A High-Impact Outreach, Testing and Implementation Campaign


ENVIRONMENTAL MODELING TOOL, PHASE 1: PROOF OF CONCEPT, 2012-2013

"Where is it? Let's (re)Use It":

A Fine-Scaled Geospatial Modeling Tool for the Strategic Targeting of Urban Stormwater Resources

Funded by: USBoR, MWD/World Water Forum


Precedent:

USBoR - Council for Watershed Health GWAM Model [2000-2010]

Baseline Study for LA Basins


A R I D L A N D S I N S T I T U T E @Woodbury University 7500 Glenoaks Blvd | Burbank CA | 91510 aridlands.org USGS


USGS

SFV Groundwater Basin


geospatial assessment model

HOW?


30-year Precipitation Normals

15m Remotely Sensed Impermeability Assessment

Geospatial Modeling Framework Phase I: Probabilistic Overlay Approach

2007 EPA Superfund Plume Dataset

2012 EPA Toxic Release Database

2013 CA Water Resources Control Board Geotracker Sites

Infiltration Model

Run Off Model

Constraint Fuzzy Logic Model

Resultant Model

1915 + 1919 USDA Soil Survey for San Fernando Valley, LA Basin

2012 CA Quaternary Surficial Geology

2003 CA Geologic Survey Soil Liquefaction

2008 NRCS SSURGO Soil Survey [incomplete]


Stormwater Runoff Model


Surficial and Subsurface Infiltration Model


Constraint Model


resultant analysis

WHERE?


Resultant:


Modeling results suggest the following:

There is an optimal pattern where stormwater infrastructural response

can be uniquely tied to the watershed and subwatersheds's hydraulic

functionality to increase the performance of stormwater recapture,

reuse and safe infiltration.

Claim


SFV Watershed Framework for Stormwater Recovery Prioritization


Taxonomy of Best Management Practices as Recognized by USEPA, Los Angeles County


Dry Ponds Infiltration Basins


On-Site: Cisterns, Dry Wells Urban Forests


DRI RESEARCH COLLABORATIVE: INTEGRATED TOOL DEVELOPMENT, 2014-

Hazel*

A Dynamic, Integrated Planning Tool for Water-Smart Urban Development in Drylands

* Hazel wood is used traditionally as an instrument for divining unseen water sources. Hazel is considered by some cultures a source of wisdom and inspiration.


2012 - 2060 LA Region Downscaled Precipitation [atmos.ucla.edu]

3m Remotely Sensed Impermeability Assessment

1915 + 1919 USDA Soil Survey for San Fernando Valley, LA Basin

2012 CA Quaternary Surficial Geology

2003 CA Geologic Survey Soil Liquefaction

2007 EPA Superfund Plume Dataset with UPDATE

2012 / 2014 EPA Toxic Release Database

2013 / 2014 CA Water Resources Control Board Geotracker Sites

Coupled Surface and Infiltration Model

Modified Run Off Model w/ Downscaled Climate Data

Constraint Fuzzy Logic Model

Dynamic Resultant Model

2008 NRCS SSURGO Soil Survey [incomplete]

Parameterized + Modified Built Environment @ Basin Scale

2012 SCAG Landuse

2012 LA Basin Building Polygons

USER DEFINED INTERVENTIONS / MODIFICATIONS:-Soft / Hard Infrastructure

PERFORMANCE + ECONOMIC DATA

2014 MODFLOW Groundwater Model

Geospatial Modeling Framework Phase II: Downscaled Climate Change Inputs + Parameterized Modifications to Built Environment

Public-Private Research Partnership:

ALI @ Woodbury University: Research Lead

TreePeople: Ecosystems Services Valuation

ARUP: Technical Oversight and Energy-Carbon Valuation of Stormwater, Recycling, and Conservation

City of Los Angeles Bureau of Engineering: Strategic Planning for Tool Development and Implementation

Collaborators:

City of LA DWP, Watershed Management Division

City of LA Bureau of Sanitation, Watershed Protection Program

LA County Department of Public Works, Integrated Flood Control Planning Division, Watershed Management Division


Divining LA: Drylands City Design for the Next 100 Years


Divining LA: Public-Private Testing, Outreach, and Implementation Partnership, 2014-Arid Lands Institute @ Woodbury University: Post-Secondary Education Outreach LeadTreePeople: Secondary Education Outreach LeadAmerican Institute of Architects | Los Angeles Chapter: Design Professions Outreach LeadARUP, AC Martin, Perkins + Will: Professional Testing and OutreachMultidisciplinary Design Programs in Southern California: Graduate and Undergraduate TestingCity of LA Bureau of Engineering: Testing and Implementation Lead

Public-Sector Collaborators:City of LA DWP, Watershed Management DivisionCity of LA Bureau of Sanitation, Watershed Protection ProgramLA County Department of Public Works, Integrated Flood Control Planning Division, Watershed Management Division


Thank you for supporting this work:

Metropolitan Water District of Southern CaliforniaUS Department of the Interior, Bureau of ReclamationSanitation Districts of Los Angeles CountyBurbank Water + PowerWater for PeopleFriends of the United NationsWoodbury University

Ethan Dingwell, Student Lead and ALI Research Intern 2013Karim Snouzzi


for more information:aridlands.org

thank you


http://aridlands.org

http://aridlands.org

aridlandsinstitute · in river basins. flood risk, water supply, and water quality are affected by...

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