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The Design for the Wetland Restoration of a Freshwater Cranberry Bog in New England Lee Weishar, Ph.D.; PWS

The Design for the Wetland Restoration of a Freshwater

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Page 1: The Design for the Wetland Restoration of a Freshwater

The Design for the Wetland

Restoration of a Freshwater

Cranberry Bog in New

England

Lee Weishar, Ph.D.; PWS

Page 2: The Design for the Wetland Restoration of a Freshwater

Points for Discussion

• History of the wetland (cranberry bog)

• Challenges for restoration

• Design alternatives

• Recommendations

• Status of Project

• Conclusions

Page 3: The Design for the Wetland Restoration of a Freshwater
Page 4: The Design for the Wetland Restoration of a Freshwater
Page 5: The Design for the Wetland Restoration of a Freshwater

1890’s 1940’s 1990’s

Page 6: The Design for the Wetland Restoration of a Freshwater

Site Demographics

• Quashnet River cranberry bog

– Subdivided into 6 units (K1 – K6)

– The entire site is approximately 24 hectares (60 acres)

– The restoration plan called for restoring ~10 hectares (25 acres)

– Natural wetland considerations • Quashnet River

• Johns Pond Outlet

• Cold groundwater seeps

Page 7: The Design for the Wetland Restoration of a Freshwater

Challenges for the Restoration

Design

• Active Cranberry Bog

• Contaminated groundwater

• Active herring run (Alewives)

• Active trout spawning area

• Objectives

– Restore/improve trout spawning

– Maintain herring run

– Maintain cranberry production

Page 8: The Design for the Wetland Restoration of a Freshwater
Page 9: The Design for the Wetland Restoration of a Freshwater

Challenges for the Restoration

Design

• Active Cranberry Bog

• Contaminated groundwater

• Active herring run (Alewives)

• Active trout spawning area

• Objectives

– Restore/improve trout spawning

– Maintain herring run

– Maintain cranberry production

Page 10: The Design for the Wetland Restoration of a Freshwater
Page 11: The Design for the Wetland Restoration of a Freshwater
Page 12: The Design for the Wetland Restoration of a Freshwater
Page 13: The Design for the Wetland Restoration of a Freshwater
Page 14: The Design for the Wetland Restoration of a Freshwater

Challenges for the Restoration

Design

• Active Cranberry Bog

• Contaminated groundwater

• Active herring run (Alewives)

• Active trout spawning area

• Objectives

– Restore/improve trout spawning

– Maintain herring run

– Maintain cranberry production

Page 15: The Design for the Wetland Restoration of a Freshwater

Restoration Site

Page 16: The Design for the Wetland Restoration of a Freshwater
Page 17: The Design for the Wetland Restoration of a Freshwater
Page 18: The Design for the Wetland Restoration of a Freshwater
Page 19: The Design for the Wetland Restoration of a Freshwater

Challenges for the Restoration

Design

• Active Cranberry Bog

• Contaminated groundwater

• Active herring run (Alewives)

• Active trout spawning area

• Objectives

– Restore/improve trout spawning

– Maintain herring run

– Maintain cranberry production

Page 20: The Design for the Wetland Restoration of a Freshwater
Page 21: The Design for the Wetland Restoration of a Freshwater
Page 22: The Design for the Wetland Restoration of a Freshwater

Challenges for the Restoration

Design

• Active Cranberry Bog

• Contaminated groundwater

• Active herring run (Alewives)

• Active trout spawning area

• Objectives

– Restore/improve trout spawning

– Maintain herring run

– Maintain cranberry production

Page 23: The Design for the Wetland Restoration of a Freshwater

Restoration Approach

• Channel designs were modeled with

HEC-RAS

• Three channel modifications were

evaluated

– Evaluate exiting conditions –pumping & no

pumping

– Partial channel realignment

– Full channel realignment

Page 24: The Design for the Wetland Restoration of a Freshwater

Low Flow, Low DO

Page 25: The Design for the Wetland Restoration of a Freshwater

Restoration Alternatives

• Channel designs were modeled with

HEC-RAS

• Three channel modifications were

evaluated

– Evaluate exiting conditions – pumping &no

pumping

– Partial channel realignment

– Full channel realignment

Page 26: The Design for the Wetland Restoration of a Freshwater

Leave this channel intact

Realign channel

Page 27: The Design for the Wetland Restoration of a Freshwater

Restoration Alternatives

• Channel designs were modeled with

HEC-RAS

• Three channel modifications were

evaluated

– Evaluate exiting conditions – pumping &no

pumping

– Partial channel realignment

– Full channel realignment

Page 28: The Design for the Wetland Restoration of a Freshwater

Realign channels

Abandon channel

Page 29: The Design for the Wetland Restoration of a Freshwater

Existing Conditions Design 3

Page 30: The Design for the Wetland Restoration of a Freshwater
Page 31: The Design for the Wetland Restoration of a Freshwater

Conclusions

• The site is highly altered

– Cranberry farming activities

– Extensive groundwater pumping

• Feasibility study shows that restoration

is possible

– Improve trout spawning habitat

– Maintain cranberry production

– Maintain herring run