# Presentation: 825888

## Nutrient and Acidity Status of Wadeable Streams in the United States- Results from the EPA’s Wadeable Streams Assessment  

- Ellen Tarquinio ( US EPA Office of Water), Alan Herlihy (Oregon State University), Dave Peck (US EPA Office of Research and Development), John Stoddard (US EPA Office of Research and Development)

## Wadeable Streams Assessment

- First statistically-valid report on the condition of the Nation’s streams
- Baseline from which to track changes over time
- Collaboration among EPA, states, tribes and other partners

- Wadeable Streams are streams, creeks, and small rivers that are shallow enough to be sampled using methods that involve wading in the water.

## Key Components

-  Randomized site selection
-  Ecological assessment based on            benthic macroinvertebrates
-  Quantitative physical habitat characterization
-  Water chemistry
-  Comprehensive quality assurance
-  Standardize/centralized data    management
-  Analysis plan for ecological assessment

## Wadeable Streams Assessment Basic Framework

- Multiple reporting scales– ecoregion level II, EPA region, nation
- Focus on basic set of core indicators
- Complement efforts in Western States and Regions
- Encourage cooperators to enhance projects
- Complete sampling in 2004

**Notes:**
I try to mention that we came up with this indicators (the use of the EMAP/ western streams methods) after significant deliberation and evaluation of other options.  This path offered the greatest density of monitoring sites because we could focus the sites in the eastern half of the US...

## Slide 5

## WSA Core Chemical Variables

- Anions
- Sulfate, Nitrate, Chloride,         Bicarbonate (calc.)
- Base Cations
- Calcium, Magnesium, Sodium, Potassium
- Other Analytes
- DOC, Color, Conductivity, Silica

- Trophic State
- Total N, Total P, TSS, Turbidity, Ammonium
- Acid-Base
- Alkalinity (ANC), pH, Dissolved inorganic carbon

## Protocols

- Field grab, shipped overnight to lab
- One 4 L cubitainer:  2 sealed syringes
- Lab process within 72 hr of collection
- Aliquot and preserve
- QA process
- Audit samples (precision, accuracy)
- Charge balance (∑anions vs. ∑cations)
- Calculated conductivity vs. measured
- ANC vs. calculated alkalinity

## WSA Aggregated Level III Ecoregions

## Reference 

- Condition class categories were set using regionally based reference conditions
- Reference sites were selected using regionally based screening factors to identify best available reference sites.
- Reference presentation Tuesday 10:45 Alan Herlihy

## National Total Phosphorus Levels 

**National Total Phosphorus Levels**** **

## National Total Nitrogen Results 

**National Total Nitrogen Results**** **

## Acidification in Steams

**Notes:**
Acidic (ANC < 0) Length = 18,044 km (1.8%)
	Dominant Acid Source
	Acidic Deposition		7,879 km (0.77%)
	Acidic Mine Drainage	*	4,677 km (0.46%)
	Natural Organic Acids	5,488 km (0.54%)
Episodic Acidification (ANC 0-25 ueq/L) = 11,212 km (1.1%)
	{streams sensitive to acidic deposition; likely become acidic during storm events}

## Regional Acidification 

## Salinity (Conductivity)  National

**Notes:**
High levels of salinity in the plains are associated with water with drawl from the sites

## Slide 18