Tradeoffs of Ecosystem Services from Wetlands in the Houston Region

 

L. James Lester1, Gregory R. Biddinger1 and Lisa A. Gonzalez1

1HARC, The Woodlands, TX, USA

Galveston Bay Watershed Ecosystem Services Planning Workshop

September 27, 2011 – Day 1 Workshop

All presentations are loaded on the GBESS website at:http://gbess.harc.edu/AgendaPresentations/tabid/2143/Default.aspx

White paper developed-The Valuation of Ecosystem Services with Relevance to the Lower Galveston Bay Watershed

Authored By: Eric Biltonen, Greg Biddinger, Jim Lester, Kenneth Bagstad, Richard Bernknopf, Marc Russell, David Saah, David Yoskowitz, and Kendra Williamson

The Starting Point: ES Workshop

Workshop supported development of local land use decision support system based on ecosystem services.

Initial focus should be “Water, Wetlands and Flooding”

Classification of Final Ecosystem Goods and Services (EPA)- Wetlands and Estuaries

Ecosystem Attributes◦ Water quality◦ Water amount◦ Plants and

animals◦ Sensory

experience

Human beneficiaries◦ Residential◦ Industry◦ Transportation◦ Government

agencies◦ Recreational

interests◦ Cultural groups◦ Agriculture◦ Subsistence users

Wetland Services vs. Land ValueMajor positive benefits of urban wetlands

◦ Stormwater retention

◦ Nutrient and pollutant assimilation

◦ Habitat

◦ Climate amelioration (heat island effect)

Major issues with urban wetland protection

◦ Loss of land value if undeveloped

◦ Increased cost of development and infrastructure if wetlands protected

◦ Lack of regulatory and nonregulatory frameworks for protection at various levels of government

LU/LC Map of Houston 2008

No DataDevelopedAgriculture/GrasslandForestWetlandBareOpen Water

Legend

Houston-Galveston Area Council

Harris County and Wetlands Harris County is currently 16.7% floodplain

◦ Reduced by development

◦ Neighboring counties are 21% – 46% floodplain

Texas Coast palustrine wetlands (prairie pothole complexes)

◦ Typical size 0.5 ac – 25 ac

◦ Typical depth 3 in – 16 in

Typical palustrine wetland stores 76% - 93% of annual input (Forbes et al. 2010)

From 1996 – 2005 Harris County lost ~4,100 acres of palustrine wetlands to development (0.3% per year)

Functional Analysis of Local Palustrine Wetland in 2008 - 2009(Forbes et al. 2010)

Prairie Pothole Wetland Complexes in Harris County

Flood Damage in Harris County

Tropical Storm Allison June 2001 (Extreme)◦Precipitation up to 37 inches in 4 days

◦30,662 insurance claims (>45,000 homes damaged)

◦$1,103,765,221 total cost

Flood Damage 1996 – 2007◦$1,162,105,186 total

◦Non-Allison = $58,339,965

High Rainfall & Flooding Are CommonHigh Monthly Rainfall Amounts

◦July 2005 = 12.96 inches

◦October 2006 = 19.26 inches

◦April 2009 = 15.61 inchesApril 18, 2009 flood

◦ 5 deaths

◦ 350 homes flooded

◦ $3.5 million in damages

NWF Study of Insured Flood Losses (Higher Ground 1998)

FEMA Database ‘78 – ‘95 (Claudette 79 and Alicia 83)

Houston & Harris County had 3,681 properties with repetitive flood loss

2.9 losses per property over 18 years$211.5 million paid out (no uninsured

losses included)

Wetland Permits and Flooding* (Trading Wetlands for Development)

11,149 Section 404 permits in Texas coastal counties 1991 – 2003

42% affecting palustrine wetlands

◦ Limited protection (2001 and 2006 supreme court rulings)

Permits in 100 year floodplain in USACE Galveston District

◦ 1991 – 2003: 32% - 41% annually

Each permit on average increases flood damage by $212 per flood (urban permits are costliest)*Brody et al. 2011

Brody et al. 2012

The Economic TradeoffUrban wetlands retain storm water and

provide other valuable services

Urban areas have high demand for land

◦ Undeveloped floodplain land in Harris County is $40K to $1M per acre

Development in Gulf Coast urban areas creates high wetland conversion activity

Profit from wetland conversion results in costs from flood damage

Economic Value of Palustrine Wetlands

Economic cost of wetland conversion is cumulative and long term

Values for development or flood mitigation are greatest in intensively developed area

Flood damage avoidance can be improved by protection of ecosystem services

◦ Land development codes and protected areas have highest negative correlation to flood damage (Brody et al. 2011)

Land use decisions currently favor economics of wetland destruction and structural flood mitigation

Information Gaps

Effect and value of wetland mitigation policy

Local spatial analysis of economic values and impacts

Ability of low impact development/ storm water retention designs to replace wetland benefits

Next StepsFunding for metro Houston

projectCompilation of local ecological

and economic dataSpatial modeling of ecosystem

services production functionsDemonstration project of

ecosystem services value in NW Harris County

Outreach to developers and local government development authorities