URBAN WATERWAYS RESTORATION STUDY South Platte River Harvard Gulch - - PowerPoint PPT Presentation

URBAN WATERWAYS RESTORATION STUDY

South Platte River • Harvard Gulch • Weir Gulch

www.DenverWaterways.com

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Study Sponsors

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Long term Schedule

Feasibility Study D i & C t ti Secure Federal Feasibility Study 3 years Complete 2017 Design & Construction 6-12+ years Secure Federal Funding

• Min. 2 years

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Tonight’s Agenda

• 1. Overview of Study
• 2. Review Existing Conditions
• 3. Present Potential Ways to Meet Study Goals
• 4. Present Next Steps

5 G th F db k

• 5. Gather Feedback

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Study Area

Harvard Gulch Harvard Gulch

dway sity Blvd ado Blvd Broad Univers Colora Evans Ave

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Other Denver Projects in the Area

Harvard Gulch Harvard Gulch

• Grant Frontier Park
• Denver Water Irrigation Conversion to Reclaimed

Water at Harvard Park and Golf Course (Pond Improvements) p )

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Study Goals

Harvard Gulch Harvard Gulch

Primary Goal: Reduce Flood Risk Secondary Goal: Ecosystem Restoration y y

Create a Healthy Waterway

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Study Goals

Harvard Gulch Harvard Gulch

C l t G l R ti

Photos: The Greenway Foundation

Complementary Goal: Recreation

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Public Input to Date

Primary Goal: Reduce Flood Risk

• General feedback of the importance of reducing the flood risk

General feedback of the importance of reducing the flood risk

• Bible Park is a good example of Detention

Secondary Goal: Ecosystem Restoration

• Preference for natural treatment (less concrete channels)
• Natural Vegetation to Support Habitat

Natural Vegetation to Support Habitat Complementary Goal: Recreation Education Opportunities

• Education Opportunities
• Improve trail connectivity

Comments & Responses are on the website DenverWaterways.com

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Flood Risk

Existing Conditions

860 t t i 500 fl d l i

• 860 structures in 500-yr floodplain
• Population at risk of approximately 2,500 people
• Current system designed to handle 10-25 yr event

y g y

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Existing Conditions

Fl d Ri k Flood Risk

t St Race St Gilpin

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Existing Conditions

Ecological Ecological Development impacts have caused a reduction in the quantity, distribution, and functional quality of riparian and wetland habitat quality of riparian and wetland habitat

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Existing Conditions

Low Functioning Wetland & Riparian Habitat Low Functioning Wetland & Riparian Habitat

• Changes in adjacent uses (urbanization)
• Lack of connectivity for migration
• Increased erosion
• Increased erosion
• Lack of native vegetation

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ALTERNATIVES

Alternative 1: No Action Alternative 1: No Action Alternative 2: Open Channel - Flood Risk Reduction Focus Alternative 3: Open Channel - Ecosystem Focus Alternative 3: Open Channel - Ecosystem Focus Alternative 4: Storm Pipe Alternative 5: Detention Alternative 5: Detention Alternative 6: Non-Structural

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Alternatives – Cross Section Depictions

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ALTERNATIVE 1

No Action

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ALTERNATIVE 2

Grass-Lined Channel - Flood Control Focus

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ALTERNATIVE 3

Wetland Channel - Environmental Focus

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ALTERNATIVE 4

Storm Pipe Alternative

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ALTERNATIVE 5

Detention Area Alternative

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ALTERNATIVE 6

Non-Structural Alternative

• Elevation
• Relocation/Buyout/Acquisition
• Berms and Floodwalls

Dry Floodproofing

• Dry Floodproofing
• Wet Floodproofing

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Alternatives – Reach 1

Logan St to S. Platte River

Enlarge Wesley St storm pipe

• r

Add secondary y storm pipe along Iliff Ave Open channel along Iliff Ave with storm pipe under Santa Fe Dr

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Alternatives – Reach 2

Ogden St to Logan St

Multiple detention areas Multiple detention areas linked and drained with storm pipes Wide channel supporting habitat

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Alternatives – Reach 3

Downing St to Ogden St g g

Wide channel supporting habitat; Narrow grass-lined channel; Wide channel supporting habitat; flow split within Downing St storm pipe Narrow grass-lined channel; flow split within Downing St storm pipe

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Alternatives – Reach 4

Race St to Downing St

Narrow Narrow grass-lined channel Wide channel ti supporting habitat

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Alternatives – Reach 5

Clayton St to Race St

Narrow grass-lined channel Wide channel supporting supporting habitat

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Alternatives – Reach 6

Colorado Blvd to Clayton St

Narrow grass-lined channel Wide Wide channel supporting habitat

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Selection Criteria

Flood Risk Reduction Benefits and Costs Reduction in Risk to Loss of Life Reduction in Risk to Loss of Life Impacts/Benefits to Habitat Impacts/Benefits to Recreation p Are these important to you? Any others?

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Study Outcomes & Schedule

Step 1: Understand existing conditions Spring 2015 Step 2: Evaluate a broad range of options Early 2016 Step 3: Selection of Preferred Plan

• Public Meeting #3

Late 2016 Propose a preferred plan C & CCD S l ti f P f d Pl L t 2017

• Corps & CCD Selection of Preferred Plan

Late 2017

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Long term Schedule

Feasibility Study D i & C t ti Secure Federal Feasibility Study 3 years Complete 2017 Design & Construction 6-12+ years Secure Federal Funding

• Min. 2 years

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Feedback & Next Steps

Collect your feedback:

• Visit the stations tonight & write comments on the plans
• Provide comments online www.DenverWaterways.com
• Call 311

Project Team Next Steps:

• Project team evaluation of the range of options
• Project team evaluation of the range of options
• Recommend a preferred option based on selection criteria
• Propose preferred plan at public meeting – Fall 2016

Propose preferred plan at public meeting Fall 2016

Tiffany Vanosdall- USACE Study PM Selena Klosowski Denver Study PM Selena Klosowski- Denver Study PM Jeremy Hamer – Denver Floodplain Manager www.DenverWaterways.com

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Q & A

www.DenverWaterways.com

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