confluence park - safety-related success of the first designed in-river us whitewater park - rick...
DESCRIPTION
Confluence Park – Looking Back at the Safety-Related Success of the First Designed In-River Whitewater Park in the U.S. The whitewater river park at Confluence Park was constructed in 1974 - becoming the nation’s first designed park constructed in an active river. The whitewater course was totally re-designed by the author and rebuilt in 1995. Located within a very urbanized area and regulated floodplain, the structures making up the features act to form a diversion and stabilize this formerly degrading river channel. While the park is one of the most heavily utilized – particularly by novices – there have been no known drownings or serious injuries within this steep-gradient whitewater park. The various features of the park employ a number of design techniques and philosophies that have proven successful over the past almost 40 years. The safety related aspects of the park will be discussed and questions and discussion will be encouraged. Rick Mclaughlin is an engineer at the Mclaughlin Whitewater Design Group – a Division of Merrick & Company. He has been the design engineer on a number of whitewater and multi-purpose recreational projects since the early 1980s. Some of these include the current configuration of Confluence Park, the 1996 Olympic Whitewater Venue, a large river restoration, diversion, and whitewater project on the American River, a very large scale river restoration and whitewater project in Columbus Georgia and a fish passage and whitewater course in Delta Colorado.TRANSCRIPT
1
Copyright © 2012 Merrick & Company - All rights reserved.
Confluence Park, Denver COLooking Back at the Safety-Related Success of the First Designed In-River Whitewater Park in the U.S.
Presented to the:
April 2014
2
Copyright © 2012 Merrick & Company - All rights reserved.
Safety
3
Copyright © 2012 Merrick & Company - All rights reserved.
Safety
4
Copyright © 2012 Merrick & Company - All rights reserved.
Safety
5
Copyright © 2012 Merrick & Company - All rights reserved.
Safety
Union Avenue Boat Chutes, Sheridan, CO
One of the Most
Dangerous Venues in
Colorado
High Flows (not the problem)
6
Copyright © 2012 Merrick & Company - All rights reserved.
Initial Conclusion
Is yours the same as a nationally recognized expert?
7
Copyright © 2012 Merrick & Company - All rights reserved.
Presentation Outline
Confluence Park Safety Performance
Safety Criteria
Criteria from the 1980s
New Objectives and Criteria
Safety Features at Confluence Park
8
Copyright © 2012 Merrick & Company - All rights reserved.
Confluence Park Safety Record
No known fatalities or serious injuries since 1976
Canoe Crunching and raft catching “holes” eliminated in 1995
No changed hydraulic conditions in these 38 years of operations
Stepped Dam added in 1996 eliminated dam related safety issues - even in this heavily used reach.
Boated by intermediate kayakers in the 10-year flood event.
9
Copyright © 2012 Merrick & Company - All rights reserved.
10
Copyright © 2012 Merrick & Company - All rights reserved.
Presentation Outline
Confluence Park Safety Performance
Safety Criteria
Criteria from the 1980s
New Objectives and Criteria
Safety Features at Confluence Park
11
Copyright © 2012 Merrick & Company - All rights reserved.
Design Criteria for Recreation Structures
http://www.udfcd.org/downloads/down_critmanual.htmhttp://cwcb.state.co.us/technical-resources/floodplain-
stormwater-criteria-manual/Pages/main.aspx
12
Copyright © 2012 Merrick & Company - All rights reserved.
Emphases of Existing UDFCD Manual
Avoidance of Overly Retentive Hydraulics
Portages
+/- Design Suggestions
Signage/Barriers
13
Copyright © 2012 Merrick & Company - All rights reserved.
Emphases of Existing UDFCD ManualOverly Retentive Hydraulics
14
Copyright © 2012 Merrick & Company - All rights reserved.
Emphasis of Existing ManualSignage/Barriers
Wide Ties and Polyester - Not Good
Barriers - Not good
15
Copyright © 2012 Merrick & Company - All rights reserved.
Emphasis of Existing ManualSignage/Barriers
No Standardized Messages or Graphics
(This sign – Not Good)
16
Copyright © 2012 Merrick & Company - All rights reserved.
Other Recommendations in Existing ManualConfluence Park Design included these:
.Issues as previously outlined
Maximum drop height of 4 feet. If more, a physical hydraulic model may be necessary.
Determine characteristics to be compatible with public safety and recreational boating.
Assess stability of the structure.
Portage paths.
Obtain peer review on the preliminary design.
Allow for follow-up rock adjustment after completion, especially for boat chutes.
17
Copyright © 2012 Merrick & Company - All rights reserved.
Use a Froude number, Fr, less than 1.5 at the toe of the drop.
Consider the slope of the downstream face of a sloping drop; 10(H) to 1(V) is common.
Provide boat chute with pilot rocks for routine boat passage of drop.
Use grouted sloping boulder or appropriately sized large ungraded sloping boulder structure.
Warning Signs
Other Recommendations in Existing ManualConfluence Park Design did not include These:
18
Copyright © 2012 Merrick & Company - All rights reserved.
Emphasis of Existing Manual
Summary:
Criteria and suggestions have demonstrated value and are still of upmost priority.
But over the past decade we have learned a lot more and the criterion are dated just like these kayakers.
19
Copyright © 2012 Merrick & Company - All rights reserved.
UpdatesAdditional “Suggestions”
Global Objectives:
20
Copyright © 2012 Merrick & Company - All rights reserved.
Proposed UpdatesAdditional “Suggestions”
Two-Dimensional Modeling
• Complex Situations
• Typical Applications
21
Copyright © 2012 Merrick & Company - All rights reserved.
Proposed UpdatesAdditional “Suggestions”
Summary of Other Suggestions:
22
Copyright © 2012 Merrick & Company - All rights reserved.
Proposed Engineering Related CriteriaObvious?
23
Copyright © 2012 Merrick & Company - All rights reserved.
Safety is More Challenging than Ever Aesthetics & Permitting
(Grout - Bad)
Innovative techniques to
reduce grout have been
successful, but ???
Pinned Boulder Technique used on the 2013 World Freestyle
Championships, Nantahala River , North Carolina
24
Copyright © 2012 Merrick & Company - All rights reserved.Photos: USBR
Multiple Slot Baffled
Safety is More Challenging than Ever Integration with Fish Passage
25
Copyright © 2012 Merrick & Company - All rights reserved.
Safety is More Challenging than Ever Diversion and Floodplain Objectives
At the New Whitewater River Park in Boise, ID: Surfers and Kayakers play in and around Gate and Intake Apparatus
26
Copyright © 2012 Merrick & Company - All rights reserved.
Safety is More Challenging than Ever Accommodating a Wide Range of Users
27
Copyright © 2012 Merrick & Company - All rights reserved.
Safety is More Challenging than Ever Limited Budgets
28
Copyright © 2012 Merrick & Company - All rights reserved.
Presentation Outline
Confluence Park Safety Performance
Safety Criteria
Criteria from the 1980s
New Objectives and Criteria
Safety Features at Confluence Park
29
Copyright © 2012 Merrick & Company - All rights reserved.
Safety Features of Confluence Park
30
Copyright © 2012 Merrick & Company - All rights reserved.
Man-Made Jetty
Design: Durable Construction Techniques
31
Copyright © 2012 Merrick & Company - All rights reserved.
Thank You
Richard McLaughlin, PE
McLaughlin Whitewater Design Group
www.mclaughlinwhitewater.com
303-964-3333