WATERSHED INVENTORY AND ASSESSMENT Module 7, part C – Assessment

Developed by: Desotelle/Yoon Updated: Dec 2004 U3-m7c-s2 Watershed Inventory and Assessment Assessment Watershed Condition Evaluation Monitoring Plan  Issues and Description  it’s about land use  Inventory  Indicators that measure watershed functions  Assessment (evaluation/monitoring)

Developed by: Desotelle/Yoon Updated: Dec 2004 U3-m7c-s3 Assessment Unit  Watershed components (functions, indicators, functional values)  Evaluation methods and examples  Summarize inventory  Choose evaluation method  Evaluate the watershed  Establish watershed goals

Developed by: Desotelle/Yoon Updated: Dec 2004 U3-m7c-s4 Watershed Components  Functions – characteristic of the watershed  Indicators – measures the function  Functional valuation – rating of the function Peterson Environmental and Desotelle Consulting, 1997

Developed by: Desotelle/Yoon Updated: Dec 2004 U3-m7c-s5 Evaluation methods  Quantitative – ability to measure an indicator and apply it to a scientific range of numbers to evaluate a rating  Qualitative – rating methodology evaluated by an individual’s perception

Developed by: Desotelle/Yoon Updated: Dec 2004 U3-m7c-s6 Example  Example based on Carver County, Minnesota’s Wetland Inventory and Functional Value Analysis  Surface water runoff function  Evaluates storage results for the attenuation of peak high and low stream flows by the storage and slow release of water in the wetland

Developed by: Desotelle/Yoon Updated: Dec 2004 U3-m7c-s7 Stream Order  The stream/ditch order number connected to the wetland basin.  High - 1st order or no stream/ditch  Moderate - 2nd or 3rd order  Low - 4th order or greater Desotelle Consulting

Developed by: Desotelle/Yoon Updated: Dec 2004 U3-m7c-s8 Wetland Area/Watershed Area  The ratio of the wetland area to the subwatershed area  High - >/= 0.02  Moderate - >/= 0.05 and <0.02  Low - <0.05 Desotelle Consulting

Developed by: Desotelle/Yoon Updated: Dec 2004 U3-m7c-s9 Gradient of Contributing Landscape  The greatest area covered by slopes ranging below from wetland to 800m out  High - >/= 6% slope  Moderate - >/=2% and <6% slope  Low - <2% slope Desotelle Consulting

Developed by: Desotelle/Yoon Updated: Dec 2004 U3-m7c-s10 Runoff Final Landscape  Combined stream order, wetland area/watershed ratio, and gradient of contributing landscape  High – stream order high, or stream order moderate and other two are high  Moderate – All other combinations  Low – All low or any combination two lows and a moderate Desotelle Consulting

Developed by: Desotelle/Yoon Updated: Dec 2004 U3-m7c-s11 Circular 39 Wetland Type  The predominant wetland type for the basin  High - Types 3, 4, 5, 6, 7  Moderate - Types 2  Low - Types 1, 90 Desotelle Consulting

Developed by: Desotelle/Yoon Updated: Dec 2004 U3-m7c-s12 Soil Hydrologic Group  The greatest area covered by soils types below from wetland to 800m out  High - A, B soils  Moderate - C, A/d, B/d soils  Low - D, C/d soils Desotelle Consulting

Developed by: Desotelle/Yoon Updated: Dec 2004 U3-m7c-s13 Wetland Area  The area of the wetland basin  High - >/= 5 acres  Moderate - >/= 1and <5 acres  Low - <1 acre Desotelle Consulting

Developed by: Desotelle/Yoon Updated: Dec 2004 U3-m7c-s14 Runoff Final Wetland  Combined Circular 39 dominant type, soil hydrologic group, and wetland area  High – All high or any combination of two highs and a moderate  Moderate – All other combinations  Low – All low or any combination two lows and a moderate Desotelle Consulting

Developed by: Desotelle/Yoon Updated: Dec 2004 U3-m7c-s15 Final Runoff Functional Value  Combining landscape and wetland functions for runoff into a final assessment  High  Both high  Moderate  All other combinations  Low  Both low or one low and one moderate Desotelle Consulting

Developed by: Desotelle/Yoon Updated: Dec 2004 U3-m7c-s16 Wetland evaluation Stormwater Function Natural Resource Function Desotelle Consulting

Developed by: Desotelle/Yoon Updated: Dec 2004 U3-m7c-s17 Oregon Watershed Assessment

Developed by: Desotelle/Yoon Updated: Dec 2004 U3-m7c-s18 Rapid Stream Assessment Technique  Inventory needs include  Channel stability  Channel scouring/sediment deposition  Physical instream habitat  Water quality  Riparian habitat conditions  Biological indicators (macroinvertebrates)  Relies on extensive field work  Prioritize which streams need this work.

Developed by: Desotelle/Yoon Updated: Dec 2004 U3-m7c-s19 Rapid Stream Assessment Technique

Developed by: Desotelle/Yoon Updated: Dec 2004 U3-m7c-s20 Impervious Cover Model  Impervious cover <10% = sensitive  Impervious cover % = impacted  Impervious cover >25% = non- supporting Photos Copyright 1999, Center for Watershed Protection

Developed by: Desotelle/Yoon Updated: Dec 2004 U3-m7c-s21 Select evaluation method(s)  There are many evaluation methods  Research  Select the methods the best fit information and issues for your watershed

Developed by: Desotelle/Yoon Updated: Dec 2004 U3-m7c-s22 Summarize the inventory  Identify missing or unavailable information.  Summarize information collected for each of the manual components  List issues that may require additional assessment or data-gathering

Developed by: Desotelle/Yoon Updated: Dec 2004 U3-m7c-s23 Evaluate the watershed  Evaluate the functions of the aquatic–riparian system, fish populations, and water quality using the assessment technique(s) that best fit the watershed issues  Describe watershed areas and issues that should be the focus for action, including habitat restoration/protection opportunities.

Developed by: Desotelle/Yoon Updated: Dec 2004 U3-m7c-s24 References  Cowardin et al. Classification of Wetlands and Deepwater Habitats of the United States FWS/OBS-79/31.  Shaw Samuel P. and Fredine C. Gordon. Wetlands of the United States Circular 39. Fish and Wildlife Service.  Center for Watershed Protection. Rapid Watershed Planning Handbook  EPA Surf your watershed  Indiana Dept of Environmental Management, Office of Water Quality  Minnesota Forest Resources Council. Sustaining Minnesota Forest Resources: Voluntary Site-Level Forest Management Guidelines for Landowners, Loggers, and Resource Managers  Oregon Watershed Assessment Manual  Rosgen, Dave. Applied River Morphology Wildland Hydrology, Pagosa springs, CO. Illustrations by Hilton Lee Silvey.  Snyder, Doug. A GIS Based Wetland Assessment Methodology for Urban Watershed Planning Minnesota Board of Soil and Water Resources.