socio-hydrology & environmental science in cities

Socio-Hydrology & Environmental Science in Cities

Laura Schifman, Ph.D.

National Academies of Science Postdoctoral Research Fellow U.S. EPA National Risk Management Research Laboratory

Today, >50% of people live in cities globally… by 2050 we can expect this number to be 66%

From Sanitary to Sustainable Cities

Ecosystem services for cities

• Flood mitigation regulating• Temperature regulationregulating• Carbon storage regulating• Air quality improvements regulating• Pollinator habitat supporting• Biodiversity supporting• Vegetation/food growth provisioning• Education cultural• Recreation cultural

freshwaterwatch.thewaterhub.org

How can cities take advantage of this?• Engineered green infrastructure solutions• Passive green infrastructure

Relies on our understanding of urban environmental processes.

phillywatersheds.org

Data-driven approaches to environmental management in citiesSite to plot scale• How do we understand

environmental processes?

• Soil assessments • Hydrologic monitoring/

measurements• Physico-chemical sampling• Impacts of disturbance (e.g.,

humans in cities)

City to regional scale• How do we understand large scale

processes?

• Geospatial land cover analysis • Field data driven numerical models• Geospatial and statistical modeling• Incidence monitoring of vector-

borne diseases and affiliated vector abundance

From the bottom up Urban Soils and their Ecosystem ServicesVolume regulation • Requires understanding of soil hydrology, function

• Depends on soil texture, location, vegetation• Engineered soil may target specifics (K, %OM,

texture) but cannot mimic all functions, processes

Water Quality• Pollutant loading driven by amount of impervious

surface • Retention/detention basins require proper

management to prevent hazardous pollutant accumulation in sediments

Mineral & humus

Mineral, leaching

Accumulation of clay from above

Partially altered parent material

Parent material

What is an urban soil?

Differences between urban and wildland soils

• Urban soils have a distinct loss in the number of horizons with depth

• Urban soils generally exhibit a loss of the B horizon

• How does this influence water cycling, plant growth, other ecosystem services?

Herrmann, Schifman, and Shuster (in prep)

Water cycling in cities – A lot of assumptions

What is the runoff volume?

What is the infiltration capacity? Drainage?

Precipitation Curve Number Soil Characteristics

Uncertainty multiplies throughout these processes

Let’s take a closer look.

• Microclimate may result in varying rainfall patterns not captured by distant rain gauges

• Unknown soil properties don’t allow us to quantify infiltration accuratelyAirport

Rain Gauge

Three common tools used in soil hydrology• USDA Rosetta

• Uses pedotransfer functions • Integrated into HYDRUS

modeling software

• SSURGO WebSoilSurvey• National soil survey datasets• Integrated into many surface

water models• National Stormwater EPA

Calculator• Uses interpolation of SSURGO

data for simulation

Which is best? … hard to tell

Texture extremes and engineered soils are not well captured

Surface Subsurface

Schifman and Shuster (under review) ASCE J. Hydrological Engineering

A closer look at Soil Hydrology in the EPA National Stormwater Calculator

• Evaluating hydraulic conductivityLocation Number of EPA

Sites % in NSWC % in SSURGO

Atlanta GA 12 8 8Camden NJ 21 10 10

Cincinnati OH 40 100 15

Cleveland OH 109 2 0

Detroit MI 55 16 0New Orleans LA 20 100 95

Majuro RMI 8 0 0Omaha NE 26 0 65Phoenix AZ 10 100 100

Portland ME 20 100 100San Juan PR 20 57 35Tacoma WA 17 12 0

Schifman et al. (2017) Journal of the American Water Resources Association

A closer look at Soil Hydrology in the EPA National Stormwater Calculator

Overall an underestimate, but dependent on location


EPA National Stormwater Calculator and soil hydrologyCase study in Watkinsville, GA

• Depending on the LID feature chosen, soil hydrology drives runoff characteristics

• Runoff depth modeling output is only as good as the input data

Interaction with pre-existing soil

Soil hydrology is important

Interaction with engineered soil

Design specification normalizes hydrology

No soil interaction

Soil hydrology plays no role


Water cyclingWhat about other ecosystem services?

Herrmann et al. (2016) Sustainability

Let’s use some of that green space!

Passive GI Active GI

Benefits from environmental processes and function

Designed according to Engineering specifications

Relies on ecosystem cycling and connects the eco-hydrological cycle

Contains engineered structures and likely to be connected to sewer system

Shuster, Herrmann, and Schifman (in prep)

Black Carbon in urban soils

• Black carbon concentrations in urban soil are influenced by

• Average annual daily traffic • City “greenness”• Depth of top soil horizon

Schifman et al. (in prep.)

Black Carbon and Green Infrastructure

Not all urban areas are like Detroit, but there is still plenty of green space

Black carbon creates a large contaminant sink in urban areas

Schifman et al. (in prep.)

unsat

Kunsat <13 mm/hr

K >13 mm/hr

Contaminant cyclingWhat about other ecosystem services?• Sustainable cities are about more than just stormwater regulation• How do we integrate multifunctionality in green infrastructure?

• Cultural, provisioning, supporting services

• Situating GI vs. Siting GI• The nexus of several contexts defines the placement and design of a GI

installation. • Assumes multiple functions of the system interact synergistically in sharing a

physical place.• Siting uses hydrologic objectives only.

Schifman et al. (2017) Water Resources Research

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U.S. EPA

A main organization connects individuals/ organizations and fosters environmental stewardship.

L. Schifman

An individual motivated to reduce their environmental impact on a parcel level or small scale.

A self-guided organization that has a single objective and approach to GI installations.

U.S. EPA

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I Group of individuals or organizations has capital in a joint environmental project with each group’s interests represented.


Situating ≠ Siting Green Infrastructure

Connected, de-centralized mesh style social network promotes interdisciplinary objectivesParticipation & inclusiveness of many organizations bring multifunctionality and versatilityAdaptation to local conditions may result in less impact, but higher multifunctionality


How can this be put into action?

• Identifies key organizations and supporting partners

• Interdisciplinary organizational structure

• Multiple objectives in green space usage

• Temporal variation in organizational structure and project objectives


Partnering with RIDOT and putting science into action

• Construction sites are a source of high sediment loads to water bodies

• RHODECAP program assess environmental compliance at construction sites

• Three inspection stages, baseline, intervention, final

Oyanedel-Craver, Schifman, and Hamel. (in prep)

How do natural and built environmental factors influence compliance?

• 9 pilot study sites that completed the program

• Sites in heavy traffic areas, removed from wetlands and water bodies showed lower compliance

Oyanedel-Craver, Schifman, and Hamel. (in prep)

Thinking ahead – how will urban areas change? • Changes in transportation (ride shares, better

public transit) may influence how we use cars • How will the transformations of parking lots, etc.

influence water management in cities?

• In areas with little rain fall runoff can be a valuable source of water

• How does increased green space or “off-the-water-grid houses” influence water governance downstream?

Thank you!

Questions?

Collaborators: Bill Shuster, US EPADustin Herrmann, Oak Ridge Institute for Science and Education Postdoctoral Research Fellow with US EPAAlessandro Ossola, Centre for Smart Green Cities, Macquarie UniversityAhjond Garmestani, US EPAMichael Tryby, US EPAJason Berner, US EPAMatt Hopton, US EPAChris Nytch, University of Puerto Rico, Rio PiedrasDanny Wiegand, US EPARoberto Barrera, Centers for Disease Control Vinka Craver, University of Rhode Island

References

• Schifman, L.A., Herrmann, D.L., Shuster, W.D., Ossola, A., Garmestani, A. and Hopton, M.E. (2017), Situating Green Infrastructure in Context: A Framework for Adaptive Socio-Hydrology in Cities. Water Resour. Res.. Accepted Author Manuscript. doi:10.1002/2017WR020926

• Schifman L.A., M. Tryby, J. Berner, W.D. Shuster. 2017. Journal of the American Water Resources Association. A matter of estimation - the role of the Environmental Protection Agency National Stormwater Calculator in framing effective stormwater management. DOI:10.1111/1752-1688.12599

• Herrmann, D. L., Shuster, W. D., Mayer, A. L., & Garmestani, A. S. (2016). Sustainability for shrinking cities. Sustainability, 8(9), 911; doi:10.3390/su8090911

socio-hydrology & environmental science in cities

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