Tryon Creek Watershed Report Card

Information
Photo shows a fish with speckled back in clear creek water and rocky stream bed.
The Tryon Creek watershed scores are above average in most areas measured by the 2019 Watershed Health Index. Upcoming projects to increase access for migrating fish will further improve the scores.

The following summary is based on data from the 2019 Watershed Health Index. The scores below are a snapshot of conditions across the entire watershed. Conditions can vary in smaller parts of the watershed.

The scores from 2015, the first year Environmental Services released the report cards, are included.

Water Quality Score: B-

Tryon Creek contains valuable aquatic habitat, but because of water quality issues the health of the watershed is low. E. coli bacteria levels often exceed state water quality standards. Untreated stormwater sends sediment and pollutants into the stream. Projects to repair and replace old sewer and stormwater pipes like the Hillsdale Crest Sewer Repair help improve water quality.

Scores for Water Quality Indicators, 2019 and 2015

Graphic shows slider bars that represent data in table on water quality scores below.
Arrow shows 2019 score. Bar shows 2015 score.

Scores are on a scale of 0 to 10 with scores of 8 or higher meaning the indicator is properly functioning. A score of 3 or lower means the indicator is not functioning properly or provides little to no support for a healthy watershed. Find more information about the indicators and how to read the scores.

Water Quality Indicator2019 Score2015 Score
Ammonia-Nitrogen9.99.9
Dissolved Copper5.95.7
Dissolved Oxygen8.68.6
E. coli2.95.3
Temperature4.95.0
Total Mercury1.81.8
Total Phosphorus6.36.6
Total Suspended Solids3.85.7

Habitat Score: B+

Habitat conditions are different throughout the watershed. The best habitat conditions exist in the Tryon Creek State Natural Area. There is room for improvement both above and below this area. Stream accessibility is a challenge, as culverts create barriers for fish passage. The recent SW Boones Ferry Bridge and Stream Restoration project replaced a culvert with a bridge which will help fish reach habitat in the upper portions of Tryon Creek.

Scores for Habitat Indicators, 2019 and 2015

Graphic shows slider bars that represent data in table on habitat scores below.
Arrow shows 2019 score. Bar shows 2015 score.

Scores are on a scale of 0 to 10 with scores of 8 or higher meaning the indicator is properly functioning. A score of 3 or lower means the indicator is not functioning properly or provides little to no support for a healthy watershed. Find more information about the indicators and how to read the scores.

Habitat Indicator2019 Score2015 Score
Bank Condition9.810.0
Floodplain Condition10.010.0
Large Wood7.44.8
Riparian Integrity7.26.9
Shallow Water RefugiaNot applicableNot applicable
Stream Accessibility1.91.5
Substrate Composition6.02.3
Tree Canopy10.010.0

Hydrology Score: B

Roads, roofs, and parking lots impact streams in the Tryon Creek watershed. These impervious surfaces create “flashy” hydrology during storm events. Heavy rains lead to stream bank instability and sediment deposits in stream beds. We are improving hydrologic conditions with projects like the Basin 3/Tryon Headwaters and Carson-Basin-SW 39th Avenue projects to manage stormwater.

Scores for Hydrology Indicators, 2019 and 2015

Graphic shows slider bars that represent data in table on hydrology scores below.
Arrow shows 2019 score. Bar shows 2015 score.

Scores are on a scale of 0 to 10 with scores of 8 or higher meaning the indicator is properly functioning. A score of 3 or lower means the indicator is not functioning properly or provides little to no support for a healthy watershed. Find more information about the indicators and how to read the scores.

Hydrology Indicator2019 Score2015 Score
Effective Impervious Area5.35.2
Stream Connectivity6.86.8

Fish and Wildlife Score: D+

Cutthroat trout and reticulate culpin are the most abundant fish detected during stream surveys. Coho and chinook salmon, steelhead, and other native fish are also present in Tryon Creek. A culvert at Highway 43 significantly blocks fish from swimming up Tryon Creek to the prime habitat in the Tryon Creek State Natural Area. Environmental Services is working on a project to remove the culvert, which will open up the entire creek to fish.

Scores for Fish and Wildlife Indicators, 2019 and 2015

Graphic shows slider bars that represent data in table on fish and wildlife scores below.
Arrow shows 2019 score. Bar shows 2015 score.

Scores are on a scale of 0 to 10 with scores of 8 or higher meaning the indicator is properly functioning. A score of 3 or lower means the indicator is not functioning properly or provides little to no support for a healthy watershed. Find more information about the indicators and how to read the scores.

Fish and Wildlife Indicator2019 Score2015 Score
Birds4.14.7
Fish2.12.0
Macroinvertebrates5.05.7

In Summary

The above-average scores for most of the Tryon Creek watershed demonstrate the impact of our work. Decades of projects to manage and treat stormwater have improved water quality, hydrology, and habitat. We are hopeful that upcoming projects will further improve water quality as well as fish and wildlife scores.

Read more about the Tryon Creek watershed.