david mallory, p.e., cfm, udfcd julie ash, p.e., walsh environmental scientists & engineers, llc...

ODE TO “RIPARIAN FLOODPLAINS”

HOW PROTECTING NATURAL SYSTEMS PROTECTS US ALL

David Mallory, P.E., CFM, UDFCDJulie Ash, P.E., Walsh Environmental Scientists &

Engineers, LLC& the Colorado Riparian Association

ASFPM– May 22, 2012

MAP OF

DISTRICT

RIPARIAN FLOODPLAINSProtect & be Protected

What are we trying to protect? Flood losses = f (riparian area losses) Natural processes for riparian floodplains Diverse ecosystem services Anthropogenic impacts Protection serves ALL!

• Good for plants and wildlife• Good for people• Good for communities• Good for business

RIPARIAN FLOODPLAINSProtect & be Protected

“Riparian Floodplain” terminologyNot new, but needs mainstream use

What are we trying to protect?

RIPARIAN FLOODPLAINSProtect & be Protected

“the green line” or “ribbons of green”

Riparian areas in the Western U.S. often provide the only visible green vegetation

They convey the contrast with the surrounding dry landscape of the arid west

What are we trying to protect?

Riparian areas comprise less than one percent of the land area of most western states, yet up to 80 percent of all wildlife species in this region of the country are dependent upon riparian areas for at least part of their life cycles.

Robert H. Wayland III, EPACongressional Testimony, June 26, 1997

The “riparian zone provides important habitat for wetland species and serves as a migratory corridor for waterfowl, shorebirds, mammals, and other animals.” U. S. Geological Survey

What are we trying to protect?

“small proportion of the landscape…essential habitat for a variety of plants and animals” U. S. Army Corps of Engineers

“there is a universal benefit in preserving the natural and beneficial functions of floodplains”Urban Drainage & Flood Control District

“Riparian communities in the Western U.S. are the most productive habitats in North America and provide irreplaceable wildlife habitat for breeding, wintering, and migration.”Bureau of land Management

What are we trying to protect?

What are we trying to protect?

Consensus that riparian floodplains are:Rare, sensitive, irreplaceableHighly functioning

Consensus across the board:Local, State, Federal agenciesResearchers and practitionersBoard & membership of:

Colorado Riparian Association (CRA)Colorado Watershed Assembly (CWA)Colorado Foundation for Water Education (CFWE)

Land managers, ranchers, watershed non-profits

What are we trying to protect?

It is not all that often that the scientific community comes to a consensus on important issues.

When it does happen, it sends a powerful message…

And helps us remember that riparian floodplains require our highest protections and stewardship…

But it doesn’t end there…

What are we trying to protect?

When we protect riparian floodplains,

they do tremendous amounts of work for us

…in myriad ways (flood protection, bed/bank/soil stability, WQ, groundwater recharge, more…)

…for free

…and in perpetuity!

(more on this to come…)

RIPARIAN FLOODPLAINSProtect & be Protected

What are we trying to protect? Flood losses = f (riparian area losses) Natural processes for riparian floodplains Diverse ecosystem services Anthropogenic impacts Protection serves ALL!

• Good for plants and wildlife• Good for people• Good for communities• Good for business

GILBERT WHITE TAUGHT US

“Floods are Acts of Nature; But Flood Losses are largely Acts of Man.”

Dr. Gilbert Fowler White 1911-2006Gustavson DistinguishedProfessor Emeritus of Geography University of Colorado

70 Years of Leadership in theField of Floodplain Management

Photo: Ken Abbott/UCB

At the same time we are losing riparian and wetland areas, flood losses are increasing

across our nation at an alarming rate $6 billion annually

by late 1900s Four-fold increase

from early 1900s Per capita damages

increased by morethan a factor of 2.5 in the previous century inreal dollar terms

And then there was Katrina, Rita, Ike…

And 2011…..

$2.2

$2.9

$2.4

$3.4

$2.2

$4.9

$3.3

$5.6

$25

$2.0

0 5 10 15 20 25 30

1910s

1920s

1930s

1940s

1950s

1960s

1970s

1980s

1990s

2000s

Billions (adjusted to 1999 dollars)

Flood losses = f (riparian area losses)

Flood Risk = P (Probability of flood X Consequences)

1974 Photo 2009 Photo

Residual Risk Can Be Increased Initial Risk Upstream Development Increases Peak Discharges Upstream Channelization Speeds Flood Peaks Approval of Development in High Risk Areas Under-communication of Risk Critical Facilities Not Protected From Flooding Lack of Early Warning and Evacuation Plans Lack of Flood Insurance Failure to Maintain Flood Control Structures

We are doing this to ourselves!

Flood losses = f (riparian area losses)

Gilbert White

“It is striking that in a century of evolving public policy the prevailing aim has been to minimize losses from floods and not to optimize the net social benefits from using floodplain resources. In simplest terms, it is the contrast between “loss reduction” and “wise use.””

Wise Use Defined

“A floodplain is being put to wise use when the activities that take place on it are compatible with both the risks to human life and property from floods and the risks to the floodplain’s natural functions posed by the human activities.” UNP 1994

RIPARIAN FLOODPLAINSProtect & be Protected

What are we trying to protect? Flood losses = f (riparian area losses) Natural processes for riparian floodplains Diverse ecosystem services Anthropogenic impacts Protection serves ALL!

• Good for plants and wildlife• Good for people• Good for communities• Good for business

Natural processes for riparian floodplains“…a floodplain can be broadly defined as a landscape feature that is periodically inundated by water from an adjacent river.”“…floodplains are geomorphic features - formed and influenced by river flows and sediment - upon which ecosystems develop and operate.”  Opperman et al, 2010, Ecologically Functional Floodplains: Connectivity, Flow Regime, and Scale. Journal of the American Water Resources Association (JAWRA) 46(2):211-226. DOI; 10.1111/j.1752-1688.2010.00426.x

Periodic flooding of overbank areas is a natural process that supports healthy riparian corridors 

RIPARIAN FLOODPLAINSProtect & be Protected

RIPARIAN FLOODPLAINSProtect & be Protected

What are we trying to protect? Flood losses = f (riparian area losses) Natural processes for riparian floodplains Diverse ecosystem services Anthropogenic impacts Protection serves ALL!

• Good for plants and wildlife• Good for people• Good for communities• Good for business

Diverse Ecosystem Services•Shading, cooling•Detritus supply•Filtering•Habitat value•Groundwater recharge•Replenish soils•Water quality•Plant life cycles (cottonwoods)

•Products (food, timber, fish, medicines)

•Climate regulation

•Bank Stabilization•Reduce erosion (fluvial, wave action)

•Endangered species protection

•Flood protection (energy breaks)

•Store & convey floodwaters

•Travel corridors•Hyporheic zone•Breeding & feeding grounds

•Biodiversity•Recreation, Tourism

RIPARIAN FLOODPLAINSProtect & be Protected

What are we trying to protect? Flood losses = f (riparian area losses) Natural processes for riparian floodplains Diverse ecosystem services Anthropogenic impacts Protection serves ALL!

• Good for plants and wildlife• Good for people• Good for communities• Good for business

RIPARIAN FLOODPLAINSProtect & be Protected

Anthropogenic impacts

Upland “square area”where small impacts may cause

only localized damage

Riparian corridor “thin, linear”where small impacts cause

significant damage, including fragmentation

RIPARIAN FLOODPLAINSProtect & be Protected

Anthropogenic impacts

Urbanization often results in a transition from intermittent to perennial flow and the conversion of grassy swale systems to stream systems with defined bed and banks.

Urbanization accelerates stream degradation that disconnects low flow channels from floodplains.

RIPARIAN FLOODPLAINSProtect & be Protected

Anthropogenic impacts

RIPARIAN FLOODPLAINSWillow Creek, Granby, ColoradoMinimal anthropogenicimpacts

Drainage Basin 109 sq.mi.

Base Flow <20 cfs

Avg Annual Peak 540 cfs

Q100 1,335 cfs

Q500 1,540 cfs

Qpeak 2011 <1,700 cfs (gage overtopped)

Anthropogenic impacts/ Land management choices

RIPARIAN FLOODPLAINSProtect & be Protected

What are we trying to protect? Flood losses = f (riparian area losses) Natural processes for riparian floodplains Diverse ecosystem services Anthropogenic impacts Protection serves ALL!

• Good for plants and wildlife• Good for people• Good for communities• Good for business

FLOODPLAIN PRESERVATION BROCHURE

Michelle Leach, Matrix Design Group

Bill DeGroot, UDFCD Michelle Slovensky, Matrix Design GroupDavid Mallory, UDFCD

Developers are in the business to make money.

If there is money to be made developing in the floodplain, they will do it.

So, we need to show them how to make money by preserving the floodplain instead of destroying it.

RIPARIAN FLOODPLAINSProtect & be Protected

Protection serves ALL!

Local governments depend on development to provide the tax revenues which sometimes leads to decisions that are damaging to the floodplain resource.

So we need to show them how to have development that provides the tax revenue, but also develops floodplains into a community amenity and asset.

RIPARIAN FLOODPLAINSProtect & be Protected

Protection serves ALL!

How to get the concepts to developers and local governments earlier in the

planning process? We had a “good examples”

page on our web site where we tried to direct developers but with limited success

We saw the opportunity to prepare a brochure which would market the floodplain as an asset to developers and communities that could be distributed early in the planning process, for instance, at a pre-application meeting

Presents to the development community an alternative to the overly emphasized engineering approach for channel design.

Illustrates projects that were economically successful.

Demonstrates that completed projects are an asset to residents who live in them and the community at large.

RIPARIAN FLOODPLAINSProtect & be Protected

Protection serves ALL!

“Too many community leaders feel they must choose between economic growth and open space protection. But no such choice is necessary. Open space protection is good for a community’s health, stability, beauty, and quality of life. It is also good for the bottom line.”

Will Rogers, President, Trust for Public LandThe Economic Benefits of Parks and Open Space

Recognize the legitimate profit motive of developers, and the need local governments have for tax revenue and amenities for their citizens

Use these needs in conjunction with preserving the natural and beneficial values of floodplains and No Adverse Impact to arrive at the best solution for all parties

Protection serves ALL!

How do we quantify the economic values of healthy natural systems and the protections they offer?

Ecosystem Services and Green Infrastructure as widely understood concepts…we’re getting there!

“Collective We”…current research & available resources…

RIPARIAN FLOODPLAINSProtect & be Protected

Protection serves ALL!

Wednesday Plenary: Economic Value of Floodplain Ecosystems

Resources for the Future

New York City:

Purchased land for watershed protection, 70,000 acres at a cost of $1.5B

Equivalent Filtration Plant $6B plus $250M/yr O&M

Milwaukee:

Greenseams Program: 2100 ac at $28M absorbs 1.3B gal

Deep Tunnel: 405M gal cost $3B

Earth Economics

“If natural flood protection, salmon productivity, storm water conveyance or drinking water services are lost, then tax districts are formed, and storm water systems, levees, hatcheries and filtration plants must be built. Real costs are incurred to replace services that were previously free.”

www.eartheconomics.org

C-3 Economic Benefits of Floodplain Management

Natural Floodplain Functions Alliance multiple partner collaboration

Natural Hazard Mitigation Association - NHMA Make Room for the River Initiative, Holland Functional Objectives for Stream Restoration

USACE ERDC Non-structural projects, USACE

RIPARIAN FLOODPLAINSProtect & be Protected

Current research/ resources:

RIPARIAN FLOODPLAINS

EPA: Draft Inventory of USEPA & USDA Research on Ecosystem Services, Jul 14, 2010

EPA: National Ecosystem Services Partnership (NESP) , Apr 20, 2010

Current research/ resources:

Current research/ resources:

Protection serves ALL!

National Oceanic and Atmospheric Administration (NOAA) Coastal Services Center & The Conservation Fund

www.greeninfrastructure.nethttp://www.conservationfund.org/green_infrastructure

course on a “Green Infrastructure” approach

Green Infrastructure Peer Exchanges

RIPARIAN FLOODPLAINSProtect & be Protected

Protection serves ALL!

Millennium Ecosystem Assessment, 2005 – international effort called for by United Nations

Current research/ resources:

Good motto:HUG A TREE

Better motto:THANK A TREE

THANK YOU!

Contemplative Viewing Areas Wildlife ViewingRaccoon TracksRiparian Planting

Photos courtesy of Michelle Slovensky

David Mallory dmallory@udfcd.org

Julie Ashjeash@walshenv.com