Extreme weather is becoming more common in our region. Flood events can impact human health and safety, and result in substantial costs to property and infrastructure. Geared toward municipal decision makers and concerned citizens, this forum provides on-the-ground examples of flood resilience strategies that can help Hudson Valley communities minimize risks while conserving financial resources.
Presentation by Wayne Reynolds, Commissioner, Delaware County Department of Public Works for a flood management forum hosted by the Cary Institute of Ecosystem Studies in Millbrook, NY on May 4, 2013.
"Subclassing and Composition – A Pythonic Tour of Trade-Offs", Hynek Schlawack
Flood Recovery Lessons Learned in Delaware County
1. Flood RecoveryFlood Recovery
Lessons Learned Along theLessons Learned Along the
WayWay
Prepared For:Prepared For:
The Cary InstituteThe Cary Institute
May 4, 2013May 4, 2013
By: Delaware County Department of Public WorksBy: Delaware County Department of Public Works
2. Requested topicsRequested topics
How has Delaware County responded toHow has Delaware County responded to
floodsfloods
Adaptations made to road infrastructureAdaptations made to road infrastructure
Introduction to practices outside ofIntroduction to practices outside of
culvertsculverts
Success stories and lessons learnedSuccess stories and lessons learned
6. Quick HistoryQuick History
Open channel flowOpen channel flow
Trapezoidal channelsTrapezoidal channels
Uniform alignmentsUniform alignments
Lined for scour protectionLined for scour protection
Bermed for flood protectionBermed for flood protection
January 19, 1996January 19, 1996
All new educationAll new education
7. FEMA Declared EventsFEMA Declared Events
11 events in 15 years11 events in 15 years
January 19, 1996January 19, 1996
November 9, 1996November 9, 1996
May 13, 2004May 13, 2004
September 18, 2004September 18, 2004
April 5, 2005April 5, 2005
June 26, 2006June 26, 2006
November 16, 2006November 16, 2006
June 19, 2007June 19, 2007
April 26, 2011April 26, 2011
August 28, 2011August 28, 2011
September 8, 2011September 8, 2011
8. Numerous Undeclared EventsNumerous Undeclared Events
June 1996June 1996
July 1998July 1998
July 2008 (FHWA Declared)July 2008 (FHWA Declared)
October 2010 (FHWA Declared)October 2010 (FHWA Declared)
9. June 2006June 2006
$14 million in damage$14 million in damage
14 bridges closed14 bridges closed
12 roads closed12 roads closed
Wide spread damageWide spread damage
Heavy damage on tributaries as opposedHeavy damage on tributaries as opposed
to 1996 which involved the main stems into 1996 which involved the main stems in
the headwatersthe headwaters
10. June 2007June 2007
Localized eventLocalized event
Watershed: 9.6 square milesWatershed: 9.6 square miles
Extremely destructiveExtremely destructive
4 lives lost4 lives lost
1 never recovered1 never recovered
Homes were lostHomes were lost
6 to 8 inches of rain in 2 hour period6 to 8 inches of rain in 2 hour period
Some reports of up to 11” in 4 hoursSome reports of up to 11” in 4 hours
In excess of $12 million in damageIn excess of $12 million in damage
11.
12. 2011 Event2011 Event
5 Bridges lost5 Bridges lost
20 damaged due to scour20 damaged due to scour
Estimated $15 million in damageEstimated $15 million in damage
Not as bad as Greene and Ulster CountiesNot as bad as Greene and Ulster Counties
13.
14. Lessons LearnedLessons Learned
We have to work with nature, we will notWe have to work with nature, we will not
win a battle with itwin a battle with it
Keep big picture in mindKeep big picture in mind
Monitor your workMonitor your work
Flooding resilience is not cheapFlooding resilience is not cheap
Important elementsImportant elements
AlignmentsAlignments
Hydraulic capacityHydraulic capacity
ScourScour
Structure typesStructure types
16. Town of HancockTown of Hancock
A Case StudyA Case Study
Fish CreekFish Creek
County Bridge on a Town RoadCounty Bridge on a Town Road
Dead end roadDead end road
Drainage Area: 11.29 square milesDrainage Area: 11.29 square miles
32. ColchesterColchester
Horse BrookHorse Brook
Damaged in 1996Damaged in 1996
Cleaned outCleaned out
TU poster childTU poster child
• National recognitionNational recognition
• DEP sponsored Dave RosgenDEP sponsored Dave Rosgen
DPW/TU CooperativeDPW/TU Cooperative
33. County Bridge 17-21County Bridge 17-21
Reconstructed in 1998Reconstructed in 1998
Stream Design by TUStream Design by TU
Incorporated floodplain drainageIncorporated floodplain drainage
Step pool designsStep pool designs
Special issues due to confluence withSpecial issues due to confluence with
BeaverkillBeaverkill
Drainage area: 2.58 Square MilesDrainage area: 2.58 Square Miles
Span: 17.3 feetSpan: 17.3 feet
Opening: 121.1 square feetOpening: 121.1 square feet
48. Town of ColchesterTown of Colchester
June, 2007June, 2007
County Route 7County Route 7
Watershed: 9.6 square milesWatershed: 9.6 square miles
81. Solutions for Delaware CountySolutions for Delaware County
Adopt hydraulic and hydrology standardsAdopt hydraulic and hydrology standards
Three sided box culvertsThree sided box culverts
Floodplain benchesFloodplain benches
Floodplain drainageFloodplain drainage
Geomorphology designsGeomorphology designs
Rock vanesRock vanes
Root wadsRoot wads
Natural vegetationNatural vegetation
82. Adopt StandardsAdopt Standards
Standards adopted by the BOSStandards adopted by the BOS
Our standards are sizing a replacementOur standards are sizing a replacement
structure to pass a Q 50 with 2 feet ofstructure to pass a Q 50 with 2 feet of
freeboard or pass Q 100 with gravity flowfreeboard or pass Q 100 with gravity flow
whichever is shorterwhichever is shorter
Standards require scour protection for theStandards require scour protection for the
design stormdesign storm
Standard is natural, living bottoms (threeStandard is natural, living bottoms (three
sided boxes or bridges as preferredsided boxes or bridges as preferred
Strict bridge takeover policyStrict bridge takeover policy
83. Three Sided BoxesThree Sided Boxes
AdvantagesAdvantages
More capacityMore capacity
Square more efficient than roundSquare more efficient than round
More scour protectionMore scour protection
Better fish passageBetter fish passage
Can precast in winterCan precast in winter
92. Town of HamdenTown of Hamden
20112011
Existing Pipe: 9’ X 5’ elliptical CMPExisting Pipe: 9’ X 5’ elliptical CMP
Watershed Area: 3.06 square milesWatershed Area: 3.06 square miles
Q50: 586 cfsQ50: 586 cfs
Q100: 681 cfsQ100: 681 cfs
Design bankfull width: 16.7 feetDesign bankfull width: 16.7 feet
93.
94.
95.
96.
97.
98.
99. Town of StamfordTown of Stamford
20122012
Watershed Area: 4.69 square milesWatershed Area: 4.69 square miles
Original crossing: 6’ diameter pipeOriginal crossing: 6’ diameter pipe
Existing Capacity: less than Q 1.25Existing Capacity: less than Q 1.25
Q 50: 1195 cfsQ 50: 1195 cfs
Q100: 1374 cfsQ100: 1374 cfs
Construction Cost: $247,000Construction Cost: $247,000
100.
101.
102.
103.
104. Great PartnersGreat Partners
Delaware County Soil and WaterDelaware County Soil and Water
Conservation DistrictConservation District
Delaware County Planning DepartmentDelaware County Planning Department
Delaware County Watershed AffairsDelaware County Watershed Affairs
New York City Department ofNew York City Department of
Environmental ProtectionEnvironmental Protection
105. Design for good wildlife habitat and thereDesign for good wildlife habitat and there
is a very good chance that you will get ais a very good chance that you will get a
durable infrastructure.durable infrastructure.
Design for durable infrastructure and thereDesign for durable infrastructure and there
is a very good chance that you will get ais a very good chance that you will get a
durable infrastructure.durable infrastructure.
106. Life as we knew it seems to have passedLife as we knew it seems to have passed
For whatever reason, the climate hasFor whatever reason, the climate has
changedchanged
We need to really think about the futureWe need to really think about the future
As an engineer, I am convinced that weAs an engineer, I am convinced that we
need to get homes and businesses out ofneed to get homes and businesses out of
the floodplainsthe floodplains
We really need to plan for future safetyWe really need to plan for future safety