Hudson Estuary WatershedHudson Estuary Watershed ...€¦ · 10/10/2013 · Teton 1976 11 Ka Loko 2006 7 Hadlock 2005 0 DlhiDelhi 2010 0 5 NYS Department of Environmental Conservation3-5

Hudson Estuary WatershedHudson Estuary Watershed Resiliency Project -Resiliency Project

Dams

Alon Dominitz P EAlon Dominitz, P.E.Chief

Dam Safety SectionDam Safety Section518-402-8185

http://www.dec.ny.gov/lands/4991.html

NYS Department of Environmental Conservation1

What is a dam?

• An artificial barrier that impounds or may impound waters (Part p y p (673)

• “An Owner must at all times operate and maintain said structure and all appurtenant structures in a safe condition” (ECL 15-0507)


pp ( )• Does not include wastewater (ex: CAFO lagoons)

Types of damsEarth dam

Gravity dam

Buttress Dam


Arch dam


Dams Sometimes FailSouth Fork 1889 2,209Teton 1976 11Ka Loko 2006 7Hadlock 2005 0D lhi 2010 0Delhi 2010 0

NYS Department of Environmental Conservation5 3-5

Internal Erosion

NYS Department of Environmental Conservation6 3-6Fowler Finch Pond Dam, Delaware County March 2011

Inadequate Spillway Capacity/ Surface Erosion

NYS Department of Environmental Conservation7 www.damsafety.org 3-7

Concrete Dam stability


Undermining of SpillwayUndermining of Spillway Toe

NYS Department of Environmental Conservation9 www.damsafety.org 3-9

Dam Hazard ClassificationDam Hazard Classification

Class BIntermediate

Hazard

Cl C

Hazard Potential

Class A Class CHigh

Hazard

Class ALow Hazard Hazard

PotentialPotential


Hazard Class Can Change


With Increasing Hazard gClassification A→C

• Dam Owner responsibilities increase• Design standards increase• Regulatory requirements increaseg y q• Time, money and effort increase


Spillway Capacity RequirementsSpillway Capacity Requirements(DEC Guidelines for Design of Dams)

Hazard Class Spillway Capacity*

A – Low 100-yearB I t di t 150% f 100B – Intermediate 150% of 100-yearC – High ½ Probable Maximum Flood

* Existing dams

Spillway capacity is the ability of the dam’s spillway system to pass inflow after routing through the reservoir. It is therefore affected the watershed, spillway hydraulics, and available storage in the reservoir.


NYS Dam Safety ProgramR l i i b DEC• Regulatory inspection by DEC engineers

• Technical review• Monitoring of Owner Dam

Safety Programs• Repair or removal of dams by p y

owners• Enforcement • Emergency planning assistanceg y p g• Repair or removal of dams

when the owner fails to follow an Order

NYS Department of Environmental Conservation14 14

NYS Dam Safety Framework• Owner Responsibility & Safety

ECL 15-0507Part 673

• Construction PermitsConstruction PermitsECL 15-0503/ 15-0511Parts 608/ 621

• Technical Standards/ Guidance“Guidelines for Design of Dams”Guidelines for Design of DamsTOGSOther industry guidelines,

research, etc.Engineering judgmentg ee g judg e

• Report of Safety InspectionsECL 15-0516

Dam Inventory - No “registry”


Dam Inventory - No registry

Dam Safety Permit Thresholds

HT ‐Feet

15’

PERMIT

REQUIRED

NO

M H HEIGH

6’

REQUIRED

PERMIT

DA

6

REQUIRED

IMPOUNDMENT STORAGE – Million Gallons

1 3


Code of Hammurabi - Section 53circa 1800 B.C.

If anyone be too lazy to keep his dam in proper condition, and does not so keep it;

if then the dam breaks and allif then the dam breaks and all the fields be flooded,

then shall he in whose dam the break occurred be sold for moneymoney,

and the money shall replace the h h d t b


corn he has caused to be ruined.

ALL DAMS BY OWNER TYPE(State Dam Inventory)

4178PRIVATE

822

454

LOCALGOVERNMENT

STATE 454

102

STATE

PUBLICUTILITY

44

UTILITY

FEDERAL


HIGH HAZARD DAMS BY OWNER TYPETYPE

(State Dam Inventory)


Owner Responsibilities

• Inspection• Maintenance• Repair• Operation• Monitoring• Emergency Action• Regulatory complianceg y p

ECL 15-0507 “An Owner of a dam … shall at all times operate and maintain said structure … in a safe condition … ‘Owner’ means any

l l bli ti h t t t i


person or local public corporation who owns, erects, reconstructs, repairs, maintains or uses a dam or other structure which impounds waters.”

NYSDEC Regulations:Part 673 “Dam Safety”Part 673 Dam Safety

What do the owners have to do?• Recordkeeping• Property Transfer

• Inspection and Maintenance Plan

Notification• Safety Inspection

• Emergency Action Plan• Annual Certification

• Engineering Assessment

• Report Flow in Auxiliary Spillway

• Financial Securityp y

• Enhanced Safety Program


Typical Dept.Inspection Reportp p


Dam Emergency Responsibilities

DAM OWNER GOVERNMENTDAM OWNER GOVERNMENT

• Warning• Detection

Warning

• Evacuation• Notification

• Evacuation

• Recovery• Prevent sudden release of water

• Recovery (impacted area)

NYS Department of Environmental Conservation23Dam Safety program oversees owner, advises governments

Emergency Action PlansEmergency Action Plans• Uniform Planning Process• Decades-old industry standard• Decades-old industry standard

for High Hazard dams• Required for Federal Energy

Regulatory CommissionRegulatory Commission (FERC) dams

• Part of FEMA’s “Model State Dam Safety Program”Dam Safety Program

• Over 60% of High Hazard dams in NY had EAP’s before the new regulations but many werenew regulations, but many were over 10 years old

• Currently over 95% of High Hazard dams have EAP’s but


Hazard dams have EAP s, but some don’t meet requirements

Emergency Action Plans - Part 673.7

– Class B – Within 24 months - August 19, 2011 (Passed!)Cl C Withi 12 th A t 19 2010 (P d!)– Class C – Within 12 months – August 19, 2010 (Passed!)

– Newly classified dams – Within 12 months of being reclassified

• Class C – full EAP• Engineer inundation map• 1 or more notification flowcharts1 or more notification flowcharts• Other provisions: preparedness, exercising, etc.

• Class B – “EAP lite”• Typically Rougher inundation map• Typically Rougher inundation map• Typically Simple notification flowchart/ list

• Both require coordination with local Emergency Mgrs!

NYS Department of Environmental Conservation25 25

Dams Provide Important Public Functions and Services

• Scenic and recreation• Water supply• Flood attenuation• Hydroelectric• Some natural resource

fbenefit depending on your perspective (different habitat)habitat)

• But, we must remember - they aren’t “natural” or permanent


“natural” or permanent

Dams Affect Streams in Many waysFundamental change from natural

waterbody to an artificial pond or lake y p

The presence of a dam can significantly alter both


upstream and downstream of the dam

Impacts Beyond the ImpoundmentImpacts Beyond the ImpoundmentDisrupts river continuum

– Barrier to upstream (and downstream) movement-not just fishnot just fish

– Alters sediment, nutrient and debris transportp

– Flow (sometimes)– Water quality can be

d d ddegraded• Temp• DO


Impacts can reach miles downstream

Other “People” Impacts• Danger to

canoeists and k kkayakers

• Upstream and downstream flooding riskflooding risk

Greenhouse gas?NYS Department of Environmental Conservation29

• Greenhouse gas?

How much do dams affect the Hudson River watershed?


You Be The JudgeOnly DEC inventory shownOnly DEC inventory shown

1900 2000

• “Golden Age of Dam Building” 1950 1970Building” 1950-1970


Current and Past Efforts: Inventory and remove barriers

•180 sq. miles•651 Culverts•651 Culverts•184 dams(64 DEC inventory)


Flood Reduction with non-FloodFlood Reduction with non-Flood Control Dams

The development of a coordinated flood control system will likely take years of y y ystudy, analysis, negotiations, funding, design and construction. It will require g qstrong and consistent local leadership. Technical and funding assistance may be g yavailable from NRCS or the USACE.





Dam Removal / BreachBenefits and Challenges

• Removal/ reduction of flood hazard from dam failure• Removal/ reduction of flood hazard from dam failure• Relief from regulatory and civil liability of dam ownership• Possible reduction of upstream flood hazard• Restoration of natural stream conditions/ fish passage• Beauty/ recreational opportunities/ habitat in stream and on formerly

flooded land

• Construction project – stream disturbance, sediment management, p j , g ,construction stormwater, flood plain development, dam safety, etc.

• Possible increase of downstream flood hazard from loss of flood attenuation

• Loss/ reduction of lake – recreation, water supply, habitat, hydrooss/ educt o o a e ec eat o , ate supp y, ab tat, yd o

Every project has a unique history, setting, concerns, and challenges. Generally, the size and complexity of the breach/ removal project is similar in magnitude to the size of the original dam construction project.


similar in magnitude to the size of the original dam construction project.


New Waterville Dam





CLOMR/ LOMRFl d M R i iFlood Map Revisions

• Physical Change to Floodplain such as Fill or Stream Changes; or

• Changes to Map and/or Study due to Updated Technical DataData

• CLOMR: Conditional Letter of Map Revision for a Proposed Project – need FEMA review of proposed revised map

• LOMR: Letter of Map Revision.• Official Revision of FIRM (and FIS) to show changes in

fl d l i fl d fl d l tifloodplains, floodways, or flood elevations• Up to 12 forms – MT-2• Community Acknowledgment Always Required


• Community Acknowledgment Always Required

Community ResponsibilityCommunity Responsibility• Must Require LOMR for Physical Changes

Causing an Increase OR Decrease in Base FloodCausing an Increase OR Decrease in Base Flood Elevation.

44 CFR 65 3– 44 CFR 65.3– Six Month Deadline

• May Not Permit Floodway Encroachment unless• May Not Permit Floodway Encroachment unless – No Increase in BFE, Engineering Analysis

Required; orRequired; or– Conditional LOMR Received

• 44 CFR 60 3(d)


• 44 CFR 60.3(d)

Information and Publications• Fact Sheets for Dam

Owners• Guidelines for Design of Dams

(1989) Owners– Dam Inspections by Owners– Burrowing Animals

(1989)• Owners Guidance Manual for

the Inspection and Maintenance of Dams in New York (1987)

– Trees and Brush Near Dams– Etc.

• Dams Inventory on Google

of Dams in New York (1987)

• Emergency Action Plans –DOW TOGS 3 1 3 Dams Inventory on Google

Earth• DRAFT Guidance for Dam

Ha ard Classification

DOW TOGS 3.1.3• Guidance for Dam Engineering

Assessments –DOW TOGS 3 1 4 Hazard Classification -

DOW TOGS 3.1.5DOW TOGS 3.1.4

http://www.dec.ny.gov/lands/4991.html


p y g


Documents

Hudson Estuary WatershedHudson Estuary Watershed ...€¦ · 10/10/2013 · Teton 1976 11 Ka Loko 2006 7 Hadlock 2005 0 DlhiDelhi 2010 0 5 NYS Department of Environmental Conservation3-5