Increasing the Role of
Statistic in Water Quality
Management Decisions
Dan McKenzie
ORD Western Ecology Division
Corvallis, Oregon
Sept. 10, 2004
Outline
•
•
•
•
Clean Water Act Requirements
Past – Before EMAP
Present – Transition (Implementation)
Future – Opportunities (Needs)
Clean Water Act
(CWA)
• Objective: “restore and maintain the
physical, chemical, and biological
integrity of the Nation’s waters”
• Section 303(c) – State Water Quality
Standards, Designated Uses & Criteria
• Section 305(b) – Report Condition of
Nation’s waters
• Section 303(d) – List of Impaired waters
and Restoration Plans
Past CWA Reports
• EPA Reports to Congress (2 yrs)
• 305(b): State Data – Inconsistent
(Designated Uses, Criteria,
Indicators, Methods)
• 303(d): State’s Assessed Waters
(Selected Sites, Listing Criteria)
• All Reviews Identified Major
Shortcomings
Florida – Summary
The state has approximately 50,000 miles of streams, 3,000 square
miles of lakes, and 4,000 square miles of estuaries.
For this report, water quality was summarized by determining the
degree of attainment for designated use for the state’s different water
body types. FDEP assessed 9,016 miles of rivers and streams,
1,302,976 acres of lakes, and 3,658 square miles of estuaries. Of the
assessed miles, 29 percent of total river miles, 20 percent of total
lake areas, and 69 percent of total estuarine areas clearly attain their
designated use (Figure 1).
Environmental Monitoring
and Assessment Program
(EMAP)
• Estimate Current Status, Trends and
Changes – Regional Basis – Known
Confidence
• Estimate Geographic Coverage and
Extent – Known Confidence
• Seek Associations – Indicators of
Stresses and Condition
• Statistical Summaries & Assessments
EMAP’s Original Guiding
Figure
Status & Association Questions
Status
Extent
of
Resource
(number,
length,
area)
Associations
Condition
Good
Fair
Poor
Nominal
Unknown
Acidity
Toxicity
Eutrophication
Habitat
Geographic Targeting
Where does Fish IBI suggest problems?
3%
35%
32%
10%
15%
32%
(Insufficient
Data)
43%
30%
Western Appalachians
North-Central Appalachians
28%
23%
15%
10%
37%
14%
44%
31%
Ridge and Blue Ridge
Valleys
EMAP Probability Survey
Example Results (complex)
Relative Ranking of Stressors
Fish Index of Biotic Integrity
Good
Sedimentation
25%
Riparian Habitat
(Insufficient
Data) 17%
17%
Mine Drainage
Poor
14%
11%
Acidic Deposition
10%
Tissue Contamination
36%
31%
24%
Fair
Phosphorus
5%
Nitrogen
5%
Acid Mine Drainage
0%
1%
10%
20%
30%
40%
% of Stream Length
Proportion of Stream Length
Introduced Fish
0%
34%
10%
20%
30%
40%
4
2002 State Report Included:
Basin - % Stream Impairment
75
<25%
25-49
50-74
>74
No Est.
37
28
23
10
27
20
67
CWA 305(b) -- Status
• States Implementing Probability
Surveys
 Streams (30+ States)
 Estuaries (Coastal States)
• EPA Office of Water
 Probability Survey or Census
 Integration of 305(b) and 303(d)
 Conducting National Stream Survey
• Aquatic Resources Monitoring
 www.epa.gov/nheerl/arm
Integrated Monitoring – Part 1
303(d) Assessment Process
305(b)
Report
Target Population Condition
& Stressors (status)
(1) EMAP Design
(probability survey)
Found Sites
(2) Estimated Status [Probabilities]
•Spatially Explicit Estimation
•Aggregation
•Classification
•Modeling
NAS
“planning”
list
Attainment-Impairment
waterbody
attaining all
uses
waterbody has high
probability of impairment
Insufficient, No
Information
Where do I need to do
follow up monitoring?
Impaired waterbody
(3) Targeted Surveys
waterbody
attaining some
uses, no
threatened uses
Example: Extending EMAP Status
Estimated IBI Condition at Reach Scale
Poor
Fair
Good
Extending EMAP Associations
Stressors Associated with IBI Status at
Reach Scale
Nominal
Unknown
Acidity
Toxicity
Eutrophication
Riparian Habitat
Potential Areas for Target Surveys
High Prob. Non-Impairment
Riparian Habitat Associations
Acidic Associations
Eutrophication Associations
Toxicity & Eutrophication
Associations
Potential Target Survey Design
Target Population: Stream
Reaches within Area Associated
with Acidic Stressors
Survey Design: Weighted by
Estimated IBI Condition (Good,
Fair, Poor)
Integrated Monitoring – Part 2
(3) Targeted Surveys
Results: Combining
intensified survey
designs, gradient
sampling, site-specific
designs as appropriate
303(d) Assessment Process
Attainment-Impairment
Waterbody impairment
confirmed
waterbody
attaining all
uses
waterbody attaining
some uses, no
threatened uses
?
303(d)
List
TMDL development
Is there an existing TMDL,
or impairment not caused by
pollutant?
Other Plans Expected to
Achieve Attainment?
Management Action
How to delist?
(4) Probability survey
designs to establish
attainment
Key Concepts & Elements
• 303(d) Requires Site Scale
Information
• Observations, Estimates, Forecasts
• Objective Basis to Categorize all
Waters, Assign Priorities
• Known Confidence – Uncertainty
• Sequential Processes
Information sources
• Probability Survey Results
• Existing Non-Probability Stations
 Fixed Station (Intensive, Few Sites)
 Traditional Monitoring Program
(Extensive, Few Observations)
• Special Study & Research Areas
• Complete Coverage (LuLc, etc.)
Potential Strategies
• Sequential Estimation
Approaches (WQ, Stressors, IBI)
• Endpoint Estimation (IBI)
• Estimate Probability of Condition
(Good, Fair, Poor)
Some Challenges
• Cause and Effect Relationships
• What to Fix/Change to Restore or
Protect
• Assignment of Sources
• Impairment Decisions (10% Obs.
Exceed Criteria)
• De-Listing Criteria
Total Maximum Daily Load
(TMDL)
• Original Focus: Point Sources
• Issues Shifted to Non-Point
Sources
• Multiple Sources & Stressors
• ~10,000 TMDLs Completed
• Substantial Workload
• Implementation, Effectiveness (?)
FUNCTIONAL COMPONENTS OF A
STREAM ECOSYSTEM
ATMOSPHERE
RIPARIAN
•
•
•
•
STREAM USE
Producer: woody plants
1° Consumer: birds
2° Consumer: birds
Decomposers
WATER COLUMN
LAND USE
•
•
•
•
Producer: macrophytes
1° Consumer: fish
2° Consumers: herptiles, fish
Decomposers
BENTHIC
WATER
TABLE
•
•
•
•
Producer: algae
1° Consumer: benthos
2° Consumer: benthos,
herptiles, fish
Decomposers: microbes
RELEVANCE TO ECOLOGICAL FUNCTION
Stressor Sources
Movement of
Materials
CONCEPTUAL MODEL: WADEABLE STREAMS
ANTHROPOGENIC
STRESSORS
Agriculture
Manufacturing
Mining
Forestry Practices
Population Density
Road Density
Channelization
Dams
HUMAN USES
Consumption
Waste Receptor
Recreation/Aestethics
Harvesting
ECOSYSTEM
SUSTAINABILITY
HABITAT
INTEGRITY
BIOTIC
INTEGRITY
ABIOTIC CHARACTERISTICS
WATER QUALITY
• Temperature
• Turbidity
• Nutrients
• Organic/inorganic
Chemicals
• Toxics
• pH
ANTHROPOGENIC
STRESSORS
Angling Pressure
Stocking
Agriculture
Manufacturing
Mining
Riparian Alterations
Invasion of non-native spp.
HABITAT QUALITY
• Substrate type
• Depth and Velocity
• Volume
• Flow regime
• Habitat
heterogeneity
• Instream Cover
BIOLOGICAL
CHARACTERISTICS
RELEVANCE TO
ECOLOGICAL
FUNCTION
CONCEPTUAL RELATIONSHIP: STRESSORS vs.
RICHNESS, ABUNDANCE, AND HABITAT METRICS
Stressor Exposure Measurements
Response Metrics
SO4
pH   Metals
 Family, Spp. Richness
 NO3
 Nutrients
 Population
 Roads
 Livestock
 Row Crops
 Logging
 Dams
 Chemicals
 Ichthyocides
 Stocking
 Abundance
 Temp
 Sensitive spp.
 O2
 Tolerant spp.
 Turbidity, Sedimentation
Riparian Modifications
 Benthic spp.
 Water Column spp.
 Long-lived spp.
Instream Fish Cover
 Non-indigenous spp.
RELEVANCE TO ECOLOGICAL FUNCTION
Opportunities
• Incorporation of Conceptual
Model Information
• Objective Evidence on Causes –
Sources
• Multiple Stressors
• Epidemiological Tools?
• Forecast Restoration –
Effort/Change, Time Sequences
Summary
• Major Improvements Occurring
• Significant Short Term
Contributions Possible
• Longer Term Opportunities
Require Innovation and Creativity
• Statistical Foundation Critical