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Matthew Taylor, P.E.
GZA GeoEnvironmental, Inc.
Senior Project Manager
A Review of the MIIC Infrastructure Status Report on
Dams
Dam Safety in Massachusetts, By the Numbers
EBC’s Dam
Management
Program
Series:
Massachusetts
Pending Dam
Safety
Legislation
April 26, 2012
Environmental
Business Council
New England, Inc.
2
Dam Safety in Massachusetts
By the Numbers
Matthew A. Taylor, P.E.
Senior Project Manager
GZA GeoEnvironmental, Inc.
Page 3
Dam Safety in Massachusetts
By the Numbers
• Objectives:
– Summarize the May 2010
Massachusetts
Infrastructure Investment
Coalition (MIIC) -
Infrastructure Status Report:
Massachusetts Dams
– Highlights of the Commonwealth of Massachusetts
Dam Safety Regulations 302 CMR 10:00
• Hazard Class vs. Condition Rating
– Major Recommendations from the 2011 Auditor of
the Commonwealth’s Report on the Massachusetts
Dam Safety Law
Page 4
Dam Safety in Massachusetts
By the Numbers
• Who is the Massachusetts Infrastructure
Investment Coalition (MIIC)?
– The Engineering Center along with ACEC/MA, BSCES,
and MALSCE organized the coalition with over 20
industry associations.
– Goals: Identifies the long term needs for infrastructure
investments to support economic develop and to improve
the quality of life for citizens of Massachusetts.
– MIIC prepared Infrastructure Status Report for
infrastructure elements including dams, bridges,
roadways, water, wastewater, etc.
– GZA assisted the MIIC in the preparation of the MIIC
Status Report on Massachusetts Dam’s in May 2010.
Page 5
Over 2,900 dams in the Commonwealth of
Massachusetts
~1,683 Jurisdictional Dams
Page 6
Almost half of the Massachusetts Dams are more
than 100 years old
0%
10%
20%
30%
40%
50%
60%
1900 1920 1940 1960 1980 2000 2010
Perc
en
tag
e o
f D
am
s i
n M
assach
usett
s
Date of Construction (prior to)
Distribution of Dams by Date of Construction
or earlier
Page 7
ASDSO Survey on Design Life of
Dams – Providence, RI, 2000
• The 100-year design life was reported most frequently.
• Data generally suggests a design life of less than 150
years is appropriate for most dams.
• More than 1,300 of Massachusetts’ dams have
exceeded their design life!
Page 8
Hazard Potential Classification
– Per 302 CMR 10.06(3)
• Hazard Potential Classification is primarily based
on potential consequence of failure, such as:
– Loss of life; and
– Damage to property or infrastructure
• Hazard Potential Classification has no relationship
to:
– Current structural integrity
– Operational status
– Flood routing capability
– Safety condition of the dam
Page 9
Hazard Potential Classification
- Per 302 CMR 10.06(3)
• High (Class I)
– Failure will likely lead to loss of life and serious damage
to homes, industrial/commercial facilities, important
public utilities, highways, railroads.
• Significant (Class II)
– Failure may lead to loss of life and damage to homes,
industrial/commercial facilities, secondary highways or
railroads, interruption of use or service of relatively
important facilities.
• Low (Class III)
– Failure may cause minimal property damage and no loss
of life expected.
Page 10
Nearly 2/3’a of Massachusetts Dams are High
or Significant Hazard to Public Safety
~1,683 Jurisdictional Dams
Source: ODS, 2010
Page 11
Condition Ratings for Dams
• Assessed by a Registered Professional
Engineer experienced in dam safety
inspections and engineering during the Phase
I Inspection.
• The Report is then subsequently submitted to
the ODS where it is accepted/denied by the
Commissioner of the DCR.
• Condition Rating is based on the overall state
of a dam and its potential risk of failure.
– Condition Rating is independent of “potential
consequence of failure”.
Page 12
Condition Ratings for Dams
• Considers the following aspects of the dam:
– Structural Integrity
– Operational and maintenance procedures
– Compliance with design standards/regulations.
• Condition Ratings include:
1. Good
2. Satisfactory
3. Fair
4. Poor
5. Unsafe
Page 13
Many of Massachusetts Dams are in a
State of Disrepair
26% of Massachusetts Dams
Source: ODS, 2010
Page 14
Condition Ratings for Dams * * Per App. D – ODS Phase I Dam Inspection Report
1. Good:
– No existing or potential deficiencies. Safe performance is
expected under all loading including the Spillway Design
Flood.
2. Satisfactory:
– Minor O&M deficiencies. Infrequent hydrologic events
would probably result in deficiencies.
3. Fair:
– Significant O&M deficiencies, no structural deficiencies.
Potential deficiencies exist at unusual loading conditions
that may realistically occur. Can be used when
uncertainties exist as to critical parameters.
Page 15
Condition Ratings for Dams * * Per App. D – ODS Phase I Dam Inspection Report
4. Poor:
– Significant structural, O&M deficiencies are
clearly recognized under normal loading
conditions.
5. Unsafe:
– Major structural, O&M deficiencies exist under
normal operating conditions.
• Note: Only Poor and Unsafe are defined in 302
CMR 10.00. App. D states if a discrepancy among
the definitions exists, 302 CMR 10.00 shall
govern.
Page 16
Condition Ratings for Dams
• Structural deficiencies(*), include but are not
limited to, the following:
• Excessive uncontrolled seepage
• Missing riprap with resulting erosion of slope
• Sinkholes (not animal burrows)
• Excessive vegetation and tree growth
• Deterioration of concrete structures
• Inoperable outlets (gates and valves)
(*) Per App. D – ODS Phase I Dam Inspection Report (not
defined in 302 CMR 10.00).
Page 17
Condition Ratings for Dams
• Per 302 CMR 10.08:
– The Commissioner shall determine whether a dam
and appurtenant features meets accepted dam
safety standards.
• The Commissioner will issue Certificates of Non-
Compliance and order dam owners to execute
detailed inspections and to bring their dams in to
compliance to reduce safety risk.
• Around 2006/2007, ODS began issuing these
Certificate of Non-Compliance to Poor or Unsafe
dams with High and Significant Hazard
Classifications.
Page 18
Hazard Potential Classification vs.
Condition Rating
• Hazard Potential Classification is primarily
based on potential consequence of failure.
• Condition Rating is primarily based on
potential risk of failure.
• Hazard Potential Classification of dam is
independent of its Condition Rating.
– Condition Rating cannot increase or decrease the
Hazard Potential Classification of the dam per the
Dam Safety Regulations.
Page 19
Auditor of the Commonwealth –
Division of Local Mandates (DLM)
• In January 2011, the DLM issued the report
entitled Local Financial Impact Review –
Massachusetts Dam Safety Law.
• The DLM’s report contains the following key
conclusions about Massachusetts dams:
– 62 municipalities own 100 critical dams that are in
Unsafe or Poor condition.
– Estimate $60M in remediation costs to reduce the
likelihood of failure of these critical dams.
– 75 of the 100 critical dams do not have Emergency
Action Plans (EAP).
The DLM report is available at: www.mass.gov/sao/dlmstudies.htm
Page 20
Auditor of the Commonwealth –
Division of Local Mandates (DLM)
• The DLM’s report contains the following major
recommendations:
1. Short Term: The Commonwealth should
ensure that the every high hazard, municipally
owned critical dam has an EAP.
2. Long Term: The Commonwealth should
establish a multi-year program of incentive
financing to target resources for remediation
of the 100 municipal critical dams.
Page 21
Auditor of the Commonwealth –
Division of Local Mandates (DLM)
• Additional Key Items in the DLM’s report:
1. Incentive Financing = Zero interest loans
funded by the Commonwealth where
repayments are earmarked and used to fund
future dam repair projects.
2. The work should be performed on a prioritized
schedule that is based on level of risk to public
safety.
3. The DLM report does not define how the
Commonwealth would secure funding for the
recommended dam remediation work.
Recommended