1. Assessing PA’s Lake Erie Tributaries
Nate Irwin
PA DEP- Office of the Great Lakes
18 April 2016

2. Waters of the Commonwealth
All waterbodies: lakes, streams, rivers, springs, wetlands…
Water body assessments are a requirement of the federal Clean Water Act
Pennsylvania has established protected uses:
Aquatic Life
Water Supply
Recreation / Fish Consumption
While there are many

3. Lake Erie Tributary Streams
Lake Erie tributaries are scheduled to be assessed again in 2016 for both aquatic life and recreation (based on E. coli bacteria, see Ch. 93)
Last assessment was 2004 (mostly Doug Ebert w/ ECDH)
Most impairments are in urbanized streams. Impairments are caused by stormwater and siltation. Results get reported to EPA

5. Stream Assessments What are Stream Assessments?
A grading of the health of the stream
Instream Comprehensive Evaluation (ICE)
Physical
Chemical
Biological

6. Physical Habitat evaluation of the site Is the diversity of
Is there a diversity of
habitat types that will
benefit a diversity of species?
Is the diversity of
organisms limited by the “number of homes in the neighborhood”?

7. Chemical Field chemistry via water quality meter
A total of 8 grab samples will be collected per site
29 tests will be performed at the lab
One time check of water purity
Limitation is that it is one moment in time

8. Biological
An assessment of the organisms that call the waterbody home.
May include macroinvertebrates (bottom dwelling “bugs”), fish, algae, plants, and/or bacteria.
Priority is given to macroinvertebrates
Dep.wv.gov

9. Why Macroinvertebrates
Easy to catch/collect
Good indicators or water quality
Well studied
Individual pollution tolerance values
Quick to rebound
“Easy” to identify

10. What’s done with Macro’s
A total of 6 samples will be collected and combined at each site via d-net.
Samples sent to Harrisburg for identification
Standard biological metrics will be carried on the data
Ultimate goal is to determine whether sites are “attaining” or “non-attaining” of their protected aquatic life use.

12. Recreational Assessment
Recreational Use assessments being led by Central Office
Planning is still underway
Based on E. coli samples
Timeframe is June-Sept.
Each site will be sampled on 5 consecutive samples within a 30 day period.
Hundreds of samples will be collected.
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14. Contact: Nate Irwin Office of the Great Lakes nirwin@pa.gov