compfpm flood plain functions

COMPREHENSIVE FLOODPLAIN MANAGEMENT: Promoting Wise Uses of Floodplains: 

COMPREHENSIVE FLOODPLAIN MANAGEMENT: Promoting Wise Uses of Floodplains CA Department of Water Resources/ CIFMCG Workshop July 2006

Comprehensive Floodplain Management Workshop: 

Comprehensive Floodplain Management Workshop Natural Floodplain Functions, Services and Societal Values

Workshop Modules: 

Workshop Modules Comprehensive FPM NFIP Overview FPM No Adverse Impact Strategies Natural Floodplain Functions and Societal Values Flood Management Economic Analysis Ecosystem Evaluation Methods Case Study Technical and Financial Assistance

Natural Floodplain Functions: 

Natural Floodplain Functions Floodplain functions includes all the physical, chemical and biological processes that sustain floodplains Floodplains perform a multitude of complex and interrelated functions which: Provide biological support Provide valuable goods and services to society

Natural Floodplain Functions: 

Natural Floodplain Functions If we can identify “societal” goods and services, then we might be able to develop monetary values If we can assign monetary values, then we can include them in economic analyses Including them in economic analyses helps us better evaluate projects that include ecosystem restoration

Floodplain Functions, Services and Societal Values: 

Floodplain Functions, Services and Societal Values Natural Floodplain Functions Manage Flows Maintain Water Supplies Maintain Water Quality Maintain Soil Quality Maintain Air Quality Maintain Plant and Animal Habitats

Floodplain Functions, Services and Societal Values: 

Floodplain Functions, Services and Societal Values Manage Flows Maintain Water Supplies Maintain Water Quality Maintain Soil Quality Maintain Air Quality Maintain Plant and Animal Habitats

Manage Flows: 

Manage Flows Functions Transport water, nutrients and organisms Spread and retain surface and subsurface water Moderate speed, force, depth and timing of flows Maintain base flows Maintain sediment balance Maintain connectivity between channel and floodplain Societal values Protection of life and property Avoided flood/sediment control infrastructure costs Value of flow-related goods and services

Manage Flows: 

Manage Flows Examples USACE estimate of annual wetland flood control benefits for Charles River, MA -- $17 Million/YR or $2,042/wetland acre Minnesota DNR cost estimate to replace wetlands flood storage in the state -- $300/AF Washington DNR cost estimate for a replacement storm water retention system equivalent to lost forestlands -- $2.4 Billion The degradation of one mile of Louisiana coastal dunes ands vegetation could increase hurricane damage by about $64,000

Floodplain Functions, Services and Societal Values: 

Floodplain Functions, Services and Societal Values Manage Flows Maintain Water Supplies Maintain Water Quality Maintain Soil Quality Maintain Air Quality Maintain Plant and Animal Habitats

Maintain Water Supplies: 

Maintain Water Supplies Functions Increase surface water storage Promote groundwater recharge Societal Values Value of goods and services produced with additional water supplies Avoid water supply infrastructure costs

Maintain Water Supplies: 

Maintain Water Supplies Examples USACE estimate of annual wetland water supply benefits for Charles River, MA – 100,000 gallons/day or About $17 per day less than local district costs or About a $6,000 annual savings in water supply costs

Floodplain Functions, Services and Societal Values: 

Floodplain Functions, Services and Societal Values Manage Flows Maintain Water Supplies Maintain Water Quality Maintain Soil Quality Maintain Air Quality Maintain Plant and Animal Habitats

Maintain Water Quality: 

Maintain Water Quality Functions Filter nutrients and impurities from runoff Process organic wastes Moderate water temperature fluctuations Societal Values Value of goods and services produced with improved water quality Avoid water treatment infrastructure costs Avoid damages to plumbing, fixtures and appliances

Maintain Water Quality: 

Maintain Water Quality Examples Louisiana tidal wetlands provide $2,500 worth of water treatment benefits per acre/year Charles River Basin wetlands can replace water treatment capital costs of $85/acre plus $1,475 in maintenance and operation costs South Carolina wetlands provide a least cost substitute for a water treatment plant costing $5 million Lake County (CA) estimates that the Middle Creek Ecosystem Restoration Project would remove up to 40% of the phosphorus entering Clear Lake

Floodplain Functions, Services and Societal Values: 

Floodplain Functions, Services and Societal Values Manage Flows Maintain Water Supplies Maintain Water Quality Maintain Soil Quality Maintain Air Quality Maintain Plant and Animal Habitats

Maintain Soil Quality: 

Maintain Soil Quality Functions Detention of particulates, compounds and elements Societal Values Value of goods and services produced with improved soil quality Avoid soil treatment costs Examples Seasonal flooding in the Cosumnes River floodplain provides benefits for the 1,000 + acres planted in organic rice and pasture

Floodplain Functions, Services and Societal Values: 

Floodplain Functions, Services and Societal Values Manage Flows Maintain Water Supplies Maintain Water Quality Maintain Soil Quality Maintain Air Quality Maintain Plant and Animal Habitats

Maintain Air Quality: 

Maintain Air Quality Functions Removal of atmospheric carbon by vegetation (carbon sequestration) Vegetation humidifies atmosphere and moderates air temperatures Societal Values Avoided air pollution treatment costs Value of improved health and comfort Improved property values

Maintain Air Quality: 

Maintain Air Quality Examples National Park Service estimates that the value of pollution removal by trees in Chicago is about $1 million/year A single rural tree can remove up to 50 lbs of particulates per year Trees can provide ambient temperature mediation and help reduce heating and cooling costs

Floodplain Functions, Services and Societal Values: 

Floodplain Functions, Services and Societal Values Manage Flows Maintain Water Supplies Maintain Water Quality Maintain Soil Quality Maintain Air Quality Maintain Plant and Animal Habitats

Maintain Plant and Animal Habitats: 

Maintain Plant and Animal Habitats Functions Maintain characteristic and diverse plant and animal communities Provide habitat interspersion and connectivity Provide breeding and feeding grounds Protect habitat for species of special concern Maintain ecological succession

Maintain Plant and Animal Habitats: 

Maintain Plant and Animal Habitats Societal Values Value of goods and services associated with habitats Improved property values Enhanced economic development Preservation values Avoided habitat enhancement/replacement costs Recreation

Maintain Plant and Animal Habitats: 

Maintain Plant and Animal Habitats Examples Urban stream restoration projects increased adjacent residential property values by $4,500 to $19,000 Riparian/wetlands restoration at new detention basins valued at $8,600 - $50,000/acre based upon regional mitigation bank costs Riparian/wetlands habitat restoration valued at $3,200/acre based upon foregone commercial development opportunities of similar property sold to a land trust

Maintain Plant and Animal Habitats: 

Maintain Plant and Animal Habitats Examples (Cont’d) Unit day values for recreational activities (exs: camping, $24; picnicking, $21; biking, $61; boating, $51) Habitat restoration can stimulate economic development (exs: Napa, San Luis Obispo)

To Summarize…: 

To Summarize… Floodplains perform a multitude of complex and interrelated functions which: Provide biological support Provide valuable goods and services to society Functions include: Manage flows Maintain water supplies Maintain water quality Maintain soil quality Maintain air quality Maintain plant and animal habitats

To Summarize…: 

To Summarize… If we can assign monetary values to floodplain functions and services, we can include them in economic analyses Including them in economic analyses helps demonstrate benefits for multi-objective projects More info?? See DWR/EPA study reports at: www.economics.water.ca.gov/documents.cfm

What’s Next?: 

What’s Next? Flood Management Economic Analysis