-- WILLETT POND DAM -PHASE I

INSPECTION / EVALUATION REPORT

Dam Name:
NID ID#:
Owner:
Town:
Consultant:
Date of Inspection:

Willett Pond Dam
MA00169
Neponset River Land Holding Association
Norwood/Walpole, MA
Fuss & O’Neill, Inc.
June 6, 2017

 EXECUTIVE SUMMARY
This Phase I Inspection/Evaluation Report details the inspection and evaluation of Willett
Pond Dam and Dike in Norwood/Walpole, Massachusetts. The inspection was performed on
June 6, 2017 by Fuss & O’Neill, Inc. Fuss & O’Neill recommends the following actions be
taken to address the deficiencies observed or found.
Willett Pond Dam is classified as a Large, High Hazard Potential (Class I) dam. The dam
was found to be in Poor condition with the following deficiencies:
x Spillway Capacity capable of passing approximately 13 percent of the
Spillway Design Flood (SDF) without overtopping
x Minor dike crest height irregularity
x Sparsely vegetated areas on the dike
The specific reason for the Poor rating is the inadequate spillway size in accordance with
302 CMR 10.14. If the spillway were adequately sized, this dam would be classified to be at least
fair.
Fuss & O’Neill recommends the following actions be taken to address the deficiencies observed
or found at the dam during this inspection and evaluation:
1. Develop a spillway design capable of safely passing the SDF
2. Remove woody vegetation from dike
3. Seed sparsely vegetated areas on the dike

Willett Pond Dam, Norwood/Walpole, Massachusetts
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 Dam Evaluation Summary Detail Sheet
1. NID ID:
June 6, 2017
MA00169
4. Inspection Date:
July 7, 2015
2. Dam Name:
Willett Pond Dam and Dike
5. Last Insp. Date:
Norwood, MA
June 6, 2019
3. Dam Location:
6. Next Inspection:
7. Inspector:
Shawn King
8. Consultant:
Fuss & O'Neill, Inc.
9a. Is Hazard Code Change Requested?:
9. Hazard Code:
High
No
POOR
10. Insp. Frequency: 2 Years
11. Overall Physical Condition of Dam:
12. Spillway Capacity (% SDF)
0-50% of the SDF or Unknown
E1. Design Methodology:
3
E7. Low-Level Discharge Capacity:
4
E2. Level of Maintenance:
4
E8. Low-Level Outlet Physical Condition:
5
E3. Emergency Action Plan:
5
E9. Spillway Design Flood Capacity:
1
E4. Embankment Seepage:
5
E10. Overall Physical Condition of the Dam:
2
E5. Embankment Condition:
4
E11. Estimated Repair Cost:
$1,046,900 - $4,910,000
E6. Concrete Condition:
4
Evaluation Description
E1: DESIGN METHODOLOGY
1. Unknown Design – no design records available
2. No design or post-design analyses
3. No analyses, but dam features appear suitable
4. Design or post design analysis show dam meets most criteria
5. State of the art design – design records available & dam meets all criteria
E2: LEVEL OF MAINTENANCE
1. Dam in disrepair, no evidence of maintenance, no O&M manual
2. Dam in poor level of upkeep, very little maintenance, no O&M manual
3. Dam in fair level of upkeep, some maintenance and standard procedures
4. Adequate level of maintenance and standard procedures
5. Dam well maintained, detailed maintenance plan that is executed
E3: EMERGENCY ACTION PLAN
1. No plan or idea of what to do in the event of an emergency
2. Some idea but no written plan
3. No formal plan but well thought out
4. Available written plan that needs updating
5. Detailed, updated written plan available and filed with MADCR, annual training
E4: SEEPAGE (Embankments, Foundations, & Abutments)
1. Severe piping and/or seepage with no monitoring
2. Evidence of monitored piping and seepage
3. No piping but uncontrolled seepage
4. Minor seepage or high volumes of seepage with filtered collection
5. No seepage or minor seepage with filtered collection
E5: EMBANKMENT CONDITION (See Note 1)
1. Severe erosion and/or large trees
2. Significant erosion or significant woody vegetation
3. Brush and exposed embankment soils, or moderate erosion
4. Unmaintained grass, rodent activity and maintainable erosion
5. Well maintained healthy uniform grass cover
E6: CONCRETE CONDITION (See Note 2)
1. Major cracks, misalignment, discontinuities causing leaks,
seepage or stability concerns
2. Cracks with misalignment inclusive of transverse cracks with no
misalignment but with potential for significant structural degradation
3. Significant longitudinal cracking and minor transverse cracking
4. Spalling and minor surface cracking
5. No apparent deficiencies

E7: LOW-LEVEL OUTLET DISCHARGE CAPACITY
1. No low level outlet, no provisions (e.g. pumps, siphons) for emptying pond
2. No operable outlet, plans for emptying pond, but no equipment
3. Outlet with insufficient drawdown capacity, pumping equipment available
4. Operable gate with sufficient drawdown capacity
5. Operable gate with capacity greater than necessary
E8: LOW-LEVEL OUTLET PHYSICAL CONDITION
1. Outlet inoperative needs replacement, non-existent or inaccessible
2. Outlet inoperative needs repair
3. Outlet operable but needs repair
4. Outlet operable but needs maintenance
5. Outlet and operator operable and well maintained
E9: SPILLWAY DESIGN FLOOD CAPACITY
1. 0 - 50% of the SDF or unknown
2. 50-90% of the SDF
3. 90 - 100% of the SDF
4. >100% of the SDF with actions required by caretaker (e.g. open outlet)
5. >100% of the SDF with no actions required by caretaker
E10: OVERALL PHYSICAL CONDITION OF DAM
1. UNSAFE – Major structural, operational, and maintenance deficiencies
exist under normal operating conditions
2. POOR - Significant structural, operation and maintenance deficiencies
are clearly recognized under normal loading conditions
3. FAIR - Significant operational and maintenance deficiencies, no structural
deficiencies. Potential deficiencies exist under unusual loading conditions
that may realistically occur. Can be used when uncertainties exist as to
critical parameters
4. SATISFACTORY - Minor operational and maintenance deficiencies.
Infrequent hydrologic events would probably result In deficiencies.
5. GOOD - No existing or potential deficiencies recognized. Safe performance
is expected under all loading including SDF
E11: ESTIMATED REPAIR COST
Estimation of the total cost to address all identified structural, operational,
maintenance deficiencies. Cost shall be developed utilizing standard
estimating guides and procedures

Changes/Deviations to Database Information since Last Inspection

  

0 

PREFACE

The assessment of the general condition of the darn reported herein was based upon available
data and visual inspections. Detailed investigations and analyses involving topographic
mapping, subsurface investigations, testing and detailed computational evaluations were beyond
the scope of this report unless reported otherwise.

In reviewing this report, it should be realized that the reported condition of the dam was based
on observations of field conditions at the time of inspection, along with data available to the
inspection team.

It is critical to note that the condition of the dam depends on numerous and constantly
changing internal and external conditions, and is evolutionary in nature. It would be incorrect
to assume that the reported condition of the dam will continue to represent the condition of the
dam at some point in the future. Only through continued care and inspection can there be any
chance that unsafe conditions be detected.

Licensed Profeccional?c Signature*

 

Christopher J. Cullen, PE.
Massachusetts License 0.: 47018
License Type: Civil

 

Project Manager
Fuss O?Neill, lnc.

302 CM 70. 00 require: impecting engineers to be Commonwealth ofMaccaclintettc Regictered Pro?mional
Engineer: wit/J a Cioil Engineering licence wit/J experience in dam sa?eg?y inlpectionc and engineering. TlJe
Department will alio accept incpection ny a Commonwealth ofManac/Jncettc Regictered Projectional Engineer
wit/J a Structural or Sanitary} Engineering licence, provided the Regictered Projectional Engineer not experience
in t/Jejield of dam engineering and impection.

 

Pond I )zlm. Nonrnod/ ?Pil??fh?i?. A [meatintro/l." Date of Inspection: June 6, 2017
Based on DCR 'I'cmpl?tc Version 3,_Iunc 2008
l?nnd 

SECTION

Page No.

EXECUTIVE SUMMARY ..................................................................................................................... I
PREFACE ............................................................................................................................................... III
SECTION 1 ............................................................................................................................................... 1
1.0

DESCRIPTION OF PROJECT ............................................................................................... 1
1.1
General ............................................................................................................................. 1
1.1.1 Authority ............................................................................................................ 1
1.1.2 Purpose of Work ............................................................................................... 1
1.1.3 Definitions ......................................................................................................... 1
1.2
Description of Project ................................................................................................... 1
1.2.1 Location ............................................................................................................. 1
1.2.2 Owner/Caretaker .............................................................................................. 2
1.2.3 Purpose of the Dam ......................................................................................... 2
1.2.4 Description of the Dam and Appurtenances ............................................... 2
1.2.5 Operations and Maintenance .......................................................................... 3
1.2.6 DCR Size Classification ................................................................................... 3
1.2.7 DCR Hazard Potential Classification ............................................................ 3
1.3
Pertinent Engineering Data .......................................................................................... 3
1.3.1 Drainage Area.................................................................................................... 3
1.3.2 Reservoir ............................................................................................................ 3
1.3.3 Discharges at the Dam Site ............................................................................. 3
1.3.4 General Elevations (feet) ................................................................................. 4
1.3.5 Main Spillway Data ........................................................................................... 4
1.3.6 Auxiliary Outlet ................................................................................................. 4
1.3.7 Design and Construction Records and History ........................................... 4
1.3.8 Operating Records ............................................................................................ 4
1.4
Summary Data Table ..................................................................................................... 4

SECTION 2 ............................................................................................................................................... 6
2.0

INSPECTION ............................................................................................................................. 6
2.1
Visual Inspection ............................................................................................................ 6
2.1.1 General Findings ............................................................................................... 6
2.1.2 Dam .................................................................................................................... 6
2.1.3 Appurtenant Structures .................................................................................... 6
2.1.4 Downstream Area ............................................................................................. 7
2.1.5 Reservoir Area ................................................................................................... 7
2.2
Caretaker Interview ........................................................................................................ 7
2.3
Operation and Maintenance Procedures..................................................................... 8
2.3.1 Operational Procedures ................................................................................... 8
2.3.2 Maintenance of Dam and Operating Facilities............................................. 8
2.4
Emergency Warning System ......................................................................................... 9
2.5
Hydrologic/Hydraulic Data .......................................................................................... 9

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 2.6

Structural and Seepage Stability .................................................................................... 9
2.6.1 Embankment Structural Stability.................................................................... 9
2.6.2 Seepage Stability ..............................................................................................10

SECTION 3 .............................................................................................................................................11
3.0

ASSESSMENTS AND RECOMMENDATIONS .............................................................11
3.1
Assessments...................................................................................................................11
3.2
Studies and Analyses ....................................................................................................11
3.3
Recurrent Maintenance Recommendations..............................................................12
3.4
Minor Repair Recommendations ...............................................................................12
3.5
Remedial Modifications Recommendations .............................................................12
3.6
Alternatives ....................................................................................................................12
3.7
Opinion of Probable Construction Costs .................................................................13

TABLES
1.1

FOLLOWING PAGE
Summary Data Table

FIGURES
Figure 1.
Figure 2.
Figure 3.
Figure 4.
Figure 5.
Figure 6.
Figure 7.
Figure 8.

END OF REPORT
Locus Plan
Aerial Photograph
Drainage Area
Downstream Area
Site Sketch (Dam)
Site Sketch (Dike)
Photo Key (Dam)
Photo Key (Dike)

APPENDICES
Appendix A.
Appendix B.
Appendix C.
Appendix D.

4

END OF REPORT
Photographs
Inspection Checklist
Previous Reports and References
Definitions

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 SECTION 1
1.0

DESCRIPTION OF PROJECT

1.1

General

1.1.1

Authority

The Neponset River Land Holding Association (NRLHA) retained Fuss and O’Neill, Inc. to
perform a visual inspection, and develop a report of conditions for Willett Pond Dam on
Bubbling Brook in Walpole and Norwood, Norfolk County, Massachusetts. This inspection
and report were performed in accordance with MGL Chapter 253, Sections 44-50
of the Massachusetts General Laws as amended by Chapter 330 of the Acts of 2002.
1.1.2

Purpose of Work

The purpose of this investigation was to inspect and evaluate the present condition of the dam
and appurtenant structures in accordance with 302 CMR 10.07 to provide information that will
assist in both prioritizing dam repair needs and planning/conducting maintenance and
operation.
The investigation was divided into four parts: 1) obtain and review available reports,
investigations, and data previously submitted to the owner pertaining to the dam and
appurtenant structures; 2) perform a visual inspection of the site; 3) evaluate the status of an
emergency action plan for the site and; 4) prepare and submit a final report presenting the
evaluation of the structure, including recommendations and remedial actions, and opinion
of probable costs.
1.1.3

Definitions

To provide the reader with a better understanding of the report, definitions of commonly used
terms associated with dams are provided in Appendix D. Many of these terms may be included
in this report. The terms are presented under common categories associated with dams which
include: 1) orientation; 2) dam components; 3) size classification; 4) hazard classification; and
5) miscellaneous.
1.2

Description of Project

1.2.1

Location

The Willett Pond Dam is intersected by the town line between Walpole and Norwood in
Norfolk County, Massachusetts. Brook Street in Norwood and Bullard Street in Walpole
traverse the dam. The center of the dam is located at latitude 42.1812ஈ North and Longitude
71.2330ஈ West (WGS 84 Datum) as determined using Google Earth Software. The dike is
located entirely within Walpole and begins several hundred feet south of the dam.
From the center of Norwood, travel south on Route 1A (Walpole Street). Turn Right on
Bullard Street. The dam is approximately 1.3 miles from the Walpole Street/Bullard Street
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 intersection. The dike can be accessed by Bullard Lane, which is located approximately ¼ mile
south of the dam.
The Willett Pond Dam drainage area is 4.8 square miles and is located within the towns of
Norwood, Walpole, Westwood, and Dover. Hawes Brook discharges from Willett Pond and
runs east to the head of Hawes Brook, which in turn runs east to the confluence with the
Neponset River. The location of Willett Pond is shown in Figure 1. An aerial photograph of
the dam and impoundment area is provided as Figure 2.
1.2.2

Owner/Caretaker

See Table 1.1 for current owner and caretaker data (names and contact information).
1.2.3

Purpose of the Dam

See Table 1.1 for the current purpose of the dam.
Willett Pond Dam was constructed in 1913 as a source for industrial water supply. The dam
is currently being used for conservation and recreation.
1.2.4

Description of the Dam and Appurtenances

The dam is a 900-foot long earth embankment with a concrete core wall. The structural height
of the dam is 25 feet. The downstream slope is approximately 2.5H:1V and grass-covered. The
upstream slope is approximately 2H:1V and riprap covered. There is an asphalt-paved public
road on the crest.
A spillway is located at the right abutment of the dam. The spillway is a concrete broad crested
structure, 28.3 feet long with vertical concrete training walls. Two vertical feet of weir boards
spanning the spillway in three bays are used to adjust water levels in the lake. A roadway bridge
spans the spillway. The discharge channel is concrete and masonry lined with a concrete wall
forming the left outlet wall and bedrock providing containment on the right side. The channel
routes flow from the lake to a wetland downstream of the dam and ultimately to Bubbling
Brook.
A brick gatehouse is located on the downstream slope of the dam. Within the gate house are
two operators for slide gates controlling flow from the lake through two 20-inch ductile iron
pipes. The pipes outlet to a concrete channel that routes water through a Parshall flume, and
then to the wetland area downstream of the dam. The wetland area begins at the toe of the
downstream embankment.
South of the dam, there is a 1,900-foot long dike with a structural height of approximately
14 feet. Like the dam, the dike is an earth embankment with a concrete core wall. There is
residential development abutting the full length of the dike. The crest of the dike is generally
15 feet wide and grass-covered. The upstream slope is generally 2H:1V, and riprap covered with
several small boat docks serving the residences. The downstream slope varies considerably,
from approximately 3H:1V to flat, where residential filling against the downstream slope has
brought the grade up to the crest elevation.
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 1.2.5

Operations and Maintenance

The NRLHA currently manages operation and maintenance activities on the dam and dike.
There is a formal Operation & Maintenance (O&M) Manual, last updated in March 2016.
NRLHA also maintains a logbook with water surface elevations, stop log position, valve
adjustments, and other maintenance activities. The O&M Manual describes operational goals
and maintenance schedules by time of year. NRLHA appears to be following their O&M
manual guidelines.
1.2.6

DCR Size Classification

Willet Pond Dam has a height of dam of approximately 25 feet and a maximum storage
capacity of 2,500 acre-feet. Refer to Appendix D for definitions of height of dam and storage.
Therefore, in accordance with Department of Conservation and Recreation Office of Dam
Safety classification, under Commonwealth of Massachusetts dam safety rules and regulations
stated in 302 CMR 10.00 as amended by Chapter 330 of the Acts of 2002, Willet Pond Dam is
a Large size structure.
1.2.7

DCR Hazard Potential Classification

The areas surrounding Bubbling Brook and the Neponset River below Willett Pond Dam, are
heavily developed with residential areas and multiple commercial and industrial complexes,
parks, and schools. It appears that a failure of the dam at maximum pool will likely cause loss
of life and serious damage to home(s), industrial or commercial facilities, important public
utilities, main highway(s) or railroad(s). Therefore, in accordance with Department of
Conservation and Recreation classification procedures, under Commonwealth of Massachusetts
dam safety rules and regulations stated in 302 CMR 10.00 as amended by Chapter 330 of the
Acts of 2002, Willett Pond Dam should be classified as a High (Class I) hazard potential
dam. The Hazard Potential Classification recommendation is consistent with the Hazard
Potential Classification on record with the Office of Dam Safety for Willett Pond Dam.
1.3

Pertinent Engineering Data

1.3.1

Drainage Area

The drainage area for Willett Pond Dam is approximately 4.8 square miles as delineated and
confirmed using USGS StreamStats online software and extends through the communities of
Norwood, Walpole, Westwood, and Dover. The topography is gently rolling. Portions of the
watershed are heavily developed. Approximately 45 percent of the watershed is made up of
farms, woodlands, and swamps. No significant impoundments are located within the watershed.
1.3.2

Reservoir

See Table 1.1 for data about normal, maximum, and spillway design flood (SDF) pools.
1.3.3

Discharges at the Dam Site

No record of discharges was available for this site. No records of overtopping were discovered
during the research for this report.
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 1.3.4
A.
B.
C.
D.
E.
F.
G.
H.
I.
1.3.5
A.
B.
C.
D.
E.

General Elevations (feet)
Top of Dam
Spillway Design Flood Pool
Normal Pool (With weir boards)
Spillway Crest (No weir boards)
Top of Dike
Upstream Water at Time of Inspection
Downstream Water at Time of Inspection
Streambed at Toe of the Dam
Low Point along Toe of the Dam

145.0
>145.0
139.9
137.7
142.0
140.0
120.5
119.5
119.5 at low level outlet

Main Spillway Data
Type
Weir Length
Weir Crest Elevation
Upstream Channel
Downstream Channel

Concrete spillway with 3 bays of weir boards
28.3 feet
139.9
137.7
137.5

The spillway travels through the bridge abutments under Bullard Street. A channel with an
average slope of 8 percent carries the water to the confluence with Bubbling Brook.
1.3.6
A.
B.
C.
D.
1.3.7

Auxiliary Outlet
Type
Size
Invert of Pipes
Control

Low-level
20-inch diameter iron pipes (2)
119.64
Knife Gates

Design and Construction Records and History

The dam was constructed in 1913. As-built drawings were included in the 1979 ACOE Phase I
Report. Repair plans and as-built plans for the Bullard Street Bridge Repair are also on file.
Maintenance of the dam since the 2015 inspection has included:
x Brush and small tree removal from the dike
x Removal of debris from the spillway discharge channel
x Exercising the gates twice per year
1.3.8

Operating Records

Operations records for the dam are kept in a log book. Maintenance items, stop-log
configuration, low-level outlet configuration, and pond elevations are routinely recorded during
site visits.
1.4

Summary Data Table

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 1.1 Summary Data Table
Required Phase I Report Data
National ID #
Dam Name
Dam Name (Alternate)
River Name
Impoundment Name
Hazard Class
Size Class
Dam Type
Dam Purpose
Structural Height of Dam (feet)
Hydraulic Height of Dam (feet)
Drainage Area (sq. mi.)
Reservoir Surface Area (acres)
Normal Impoundment Volume (acre-feet)
Max Impoundment Volume ((top of dam) acre-feet)
SDF Impoundment Volume* (acre-feet)
Spillway Type
Spillway Length (feet)
Freeboard at Normal Pool (feet)
Principal Spillway Capacity* (cfs)
Auxiliary Spillway Capacity* (cfs)
Low-Level Outlet Capacity* (cfs)
Spillway Design Flood* (flow rate - cfs)
Winter Drawdown (feet below normal pool)
Drawdown Impoundment Vol. (acre-feet)
Latitude
Longitude
City/Town
County Name
Public Road on Crest
Public Bridge over Spillway
EAP Date (if applicable)
Owner Name
Owner Address
Owner Town
Owner Phone
Owner Emergency Phone
Owner Type
Caretaker Name
Caretaker Address
Caretaker Town
Caretaker Phone
Caretaker Emergency Phone
Date of Field Inspection
Consultant Firm Name
Inspecting Engineer
Engineer Phone Number

Data Provided by the Inspecting Engineer
MA00169
Willett Pond Dam and Dike
0
Bubbling Brook
Willett Pond
High
Large
Earth Embankment
Recreation/Conservation
25
20
4.8
240
1736
2500
>2500
Box Culvert/Channel
28.3
5
250/650 (with/without stop logs)
N/A
96 (at max pool)
1/2PMF, 4,830
NA
NA
42.1812N
71.233W
Norwood
Norfolk
Yes
Yes
3/17/2016
Neponset River Land Holding Assoc.
2173 Washington Street
Canton, MA 02021
781-575-0354
781-575-0354
Private Association or other non-profit
Tom Palmer & Ian Cooke
2173 Washington Street
Canton, MA 02021
781-575-0354
978-467-5271
6/6/2017
Fuss & O'Neill, Inc.
Shawn King
860-646-2469

*In the event a hydraulic and hydrologic analysis has not been completed for the dam, indicate "No H&H" in this table, recommendation
section shall include specific recommendation to hire a qualified dam engineering consultant to conduct analysis to determine spillway
adequacy in conformance with 302 CMR 10.00.

Willett Pond Dam, Norwood/Walpole

Date of Inspection: June 6, 2017

 SECTION 2
2.0

INSPECTION

2.1

Visual Inspection

Willett Pond Dam was inspected on June 6, 2017. At the time of the inspection, the weather
was 85°F and clear. Photographs to document the current conditions of the dam were taken
during the inspection and are included in Appendix A. The level of the impoundment was
140.0 feet (normal pool). Underwater areas were not inspected. A copy of the inspection
checklist is included in Appendix B.
2.1.1

General Findings

In general, Willett Pond Dam was found to be in Poor condition due to the inadequate spillway
size. If the spillway were adequately sized, this dam would be classified to be Fair or possibly
Satisfactory. The specific concerns are identified in more detail in the sections below:
2.1.2
x

Dam

Abutments

o The abutments were in satisfactory condition.

x

Upstream Slope

o The upstream face of the dam is an earthen slope with armor consisting of
placed rip-rap.

x

Crest

o The roadway on the dam crest was raised approximately two feet at some point
in the past, so the original dam crest is not visible. The asphalt roadway is
cracked and rutted with age. There are some signs of the road base course
eroding in places.

x

Downstream Slope

o The downstream slope is approximately 2.5:1 with satisfactory vegetative cover.

2.1.3

Appurtenant Structures

x Primary Spillway
The spillway structure has a concrete floor and side walls. A steel and concrete bridge
spans the spillway. The base of the spillway is concrete. The upper half of the structure
and upstream training walls are formed and poured concrete and in good condition. Two
concrete pier remnants are located within the spillway. These piers are part of the old
bridge structure that was left in place when the Bullard Street Bridge was reconstructed in
2007. The piers support three bays of wooden weir boards that appeared to be in good
condition. No seepage was observed below or around the spillway.

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 x Low-Level Outlet
The low-level outlet consists of two 20-inch diameter ductile iron pipes. The outlets are
controlled by knife gates located in a gatehouse on the downstream slope of the dam. The
gates are typically left in a partially open position to maintain minimum flows to Bubbling
Brook and the Neponset River. The valve operators are regularly maintained. A Parshall
flume is located at the discharge of the low level outlet pipes.
x Dike
The dike consists of a 1,900-foot-long earthen embankment with a concrete core wall.
Abutting property owners have historically accessed Willett Pond across the dike. Small
birch trees are located along approximately 40 percent of the waterline and upstream face
of the dike. The crests of the dike and the downstream slope have varying degrees of
vegetation, but the majority of the dike is covered with grass. It was noted that areas of
sparse vegetation observed in the past are establishing vegetation during this inspection, but
additional areas were observed with little to no vegetation. Riprap protection was observed
on much of the upstream dike embankment. In some areas, abutters have effectively
buttressed the dike by substantially filling the areas down gradient of the dike. In other
areas the downstream slope of the dike has slopes as steep as 2:1.
2.1.4

Downstream Area

The area immediately below the dam is primarily wetland and marsh with thick brush and small
streams. Guild Pond is located approximately 300 feet downstream of the dam.
2.1.5
x
2.2

Reservoir Area
The shores of Willett Pond are generally mild to medium sloped. The shores are a mix
of well-maintained lawns at private residences and wooded areas elsewhere.
Caretaker Interview

Mr. Ian Cooke of NRLHA provided updated information concerning activities, maintenance
operation of the dam and dike. The information provided by them has been incorporated into
this report. Information of note includes:
x No Dam or Dike overtopping events are indicated in their records
x The dam is managed as part of the Neponset River Watershed for conservation
and recreation
x An O&M Manual is kept up to date
x Staff is regularly trained and is knowledgeable about maintenance and
emergency procedures
x An Emergency Action Plan (EAP) is on file with the Office of Dam Safety
x As-Built Plans are available

Willett Pond Dam, Norwood/Walpole, Massachusetts
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Date of Inspection: June 6, 2017
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 2.3

Operation and Maintenance Procedures

NRLHA keeps an updated O&M Manual. The manual was last updated in March 2016, with
the addition of the EAP as an addendum to the O&M manual.
2.3.1

Operational Procedures

The O&M Plan establishes goals for operation of the dam. The basic operational goal is to
ensure adequate flow for fish spawning, survival, and overwintering while maintaining an
adequate pool for recreation on the pond. The plan divides the year into three periods and
establishes minimum discharges and target pond water levels for each period. The O&M Plan
references the EAP for additional emergency operation procedures.
The low level outlet gates are lubricated and exercised every spring and fall by opening and
closing the valves fully before returning them to their appropriate seasonal settings.
2.3.2

Maintenance of Dam and Operating Facilities

The plan defines four maintenance priorities, including:
x Maintaining the ground cover on the dam and dike with periodic grass planting and
mowing, preventing erosion and allowing for efficient dam inspection.
x Scheduling regular tree and brush cutting and spraying stumps to prevent roots from
penetrating the dam and dike.
x Keeping the spillway clear and maintaining the desired flow.
x Maintaining the integrity of the valve house and exercising the valves.
The plan calls for dam visits as necessary to meet seasonal operational goals, with monthly
inspections from March through November, and one winter inspection in January. Additionally,
the plan calls for inspections prior to or after extraordinary weather events, such as: prior to
predicted major rainstorms or snow melts, during or after extremely heavy rainfall or a severe
storm, during or after a severe windstorm, and following an earthquake in the area.
Specific tasks addressed in the plan include:
x Trash pick-up, annually on Earth Day and at other times as deemed necessary.
x Exercising low-level outlet valves each spring and fall.
x Filling, marking, and monitoring animal holes and removal of nuisance animals
as necessary.
x Inspecting, realigning, and replacing erosion control wattles as necessary each
May and October.
x Spot seeding every April and September as needed.
x Mowing of warm season grass in May, June, August, and September or as needed.
x Spraying weeds and poison ivy with herbicide or manually removing monthly or as
necessary.
x Spraying woody vegetation on the water side of dike and dam with herbicide
in September, if needed.
Willett Pond Dam, Norwood/Walpole, Massachusetts
8
Date of Inspection: June 6, 2017
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 x
x
x
2.4

Cutting woody vegetation to the ground after it has been killed.
Removing obstructions from the spillway during monthly inspections.
Repairing dislodged riprap as needed.
Emergency Warning System

A formal EAP, last updated in 2016, is on file with the DCR Office of Dam Safety, the local
Emergency Management Office, and in the NRLHA offices.
2.5

Hydrologic/Hydraulic Data

Willett Pond Dam is classified as a Large size, High hazard (Class I) potential dam and in
accordance with the MGL 302 CMR 10.00, the spillway design flood is the ½-PMF flood event.
The information in the table below was obtained from our hydrologic and hydraulic assessment
of the dam performed as part of the Phase II Investigation. The numbers presented represent
the spillway capacity without weir boards in place. Peak SDF inflow was estimated at 4,883 cfs.
The routed SDF outflow was estimated at 4,811 cfs without weir boards and 4,830 with weir
boards installed.
A.
B.
C.
D.
E.
F.

Spillway Design Flood (SDF) Return Period
SDF Inflow (cfs)
SDF Outflow (cfs)
Principal Spillway Capacity (cfs)(no weir boards)
Low-level Outlet Capacity (cfs)
Maximum Depth of Overtopping for SDF (ft) (if applicable)

½ PMF
4,883 cfs
4,830 cfs
650 cfs
96 cfs
1.8 ft

There are no records of embankment overtopping at the dam or dike. However, our study of
the dam indicates the dike will overtop by as much as 1.8 feet during the SDF.
2.6

Structural and Seepage Stability

Stability and seepage analyses were performed as part of the 2011 Phase II Investigation
performed by Fuss & O’Neill.
2.6.1

Embankment Structural Stability

Dam embankment stability analyses performed as part of the recent Phase II investigation
indicated factors of safety of 1.5 against deep failure under full pool conditions and 1.16 under
seismic, full pool conditions.

Willett Pond Dam, Norwood/Walpole, Massachusetts
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Date of Inspection: June 6, 2017
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 2.6.2

Seepage Stability

The toe of the dam, and three locations along the toe of the dike (as shown in the figures) are
damp, but no seepage flow was noted. The moist conditions at the toe of the dam are most
likely due to backwater from the wetland and pond immediately downstream of the dam. The
seepage observed at the toe of the dike does not appear to be causing any instability. The wet
areas at the toe of the dike all correspond to drainage collection areas at the toe and are not
likely due to seepage. No subsidence, sinkholes or sediment transport was noted during the
inspection.
The core walls in the dam and dike have a significant effect on seepage. Monitoring well
elevations and seepage analysis of the dam during the Phase II investigation indicated that the
core walls are performing adequately.

Willett Pond Dam, Norwood/Walpole, Massachusetts
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Date of Inspection: June 6, 2017
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 SECTION 3
3.0

ASSESSMENTS AND RECOMMENDATIONS

3.1

Assessments

In general, the overall condition of Willett Pond Dam is Poor, primarily due to the low spillway
capacity. The dam was found to have the following deficiencies:
1. Spillway Capacity only capable of passing approximately 13 percent of the Spillway
Design Flood (SDF) without overtopping
2. Minor irregularities of dike crest height
3. Sparse vegetation cover in areas on dike
4. Woody vegetation on dike
The 2015 Phase I Report listed the condition of Willett Pond Dam as Poor. The table below
lists the previously identified deficiencies and the current status of those deficiencies:
Previously Identified Deficiency

Resolution or Current Condition

Spillway Capacity only capable of passing
approximately 13 percent of the Spillway
Design Flood (SDF) without overtopping

Unresolved – Alternatives provided in the
Phase II investigation

Minor irregularities of dike crest height

Unresolved – Irregularities remain

Sparse vegetative cover on dike

Partially Resolved – Some areas reestablishing
cover.

Woody vegetation on dike

Unresolved – Woody vegetation persists on
dike

The following recommendations and remedial measures generally describe the recommended
approach to address current deficiencies at the dam. Prior to undertaking recommended
maintenance, repairs, or remedial measures, the applicability of environmental permits needs to
be determined for activities that may occur within resource areas under the jurisdiction of local
conservation commissions, MADEP, or other regulatory agencies.
3.2

Studies and Analyses

The Phase II Report has been completed in 2011. Alternatives for rehabilitation of the dam
were provided, principally involving the inadequate capacity of the spillway to accommodate
the SDF. No additional studies are recommended at this time.

Willett Pond Dam, Norwood/Walpole, Massachusetts
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Date of Inspection: June 6, 2017
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 3.3

Recurrent Maintenance Recommendations

The annual maintenance procedures indicated in the O&M Manual should continue to be
followed. The primary tasks from the plan include:
x Exercising low-level outlet valves each spring and fall.
x Filling, marking, and monitoring animal holes and removal of nuisance animals
as necessary.
x Inspecting, realigning, and replacing erosion control wattles as necessary each
May and October.
x Spot seeding every April and September as needed.
x Mowing of warm season grass in May, June, August, and September.
x Spraying weeds and poison ivy with herbicide monthly or as necessary.
x Spraying woody vegetation on the water side of dike and dam with herbicide
in September when needed.
x Cutting woody vegetation to the ground after it has been killed.
x Removing obstructions from the spillway during monthly inspections.
3.4

Minor Repair Recommendations
x

3.5

Remove woody vegetation, especially non-birch varieties, from dike
Remedial Modifications Recommendations

The only major remedial recommendation concerns the inadequacy of the spillway to
accommodate the design storm, which is the ½ PMF for High Hazard dams. This issue has
been addressed in the Phase II investigation.
3.6

Alternatives

As stated above, the spillway capacity issue was examined in the Phase II investigation. Several
alternatives were presented, including breaching the dam, widening and/or deepening the
spillway, raising the dike elevation, raising the dam elevation, armoring the dike to overtop
safely, installing a new weir, installing a new gate and combinations of these. It has been
determined that the cross sectional area beneath the bridge needs to be increased in area to
accommodate the SDF under any scenario. The fixed spillway length must be increased to
350 feet. Alternatively, a bottom-hinged gate is also being considered. At this time, alternative
spillway solutions are being considered.

Willett Pond Dam, Norwood/Walpole, Massachusetts
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Date of Inspection: June 6, 2017
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 3.7

Opinion of Probable Construction Costs

Costs for repair of the dam are dominated by the cost of providing adequate spillway capacity
for the SDF. Costs for several spillway alternatives were presented in the Phase II investigation.
All costs included enlarging the cross-sectional bridge opening area. The following table
summarizes the cost ranges for each alternative considered.
Spillway Alternative
Hinged bottom gate
Long fixed concrete ogee weir
Raise dike, short ogee weir
Lower water level, short ogee weir

Cost Range
$1,046,000
$2,240,000
$2,292,000
$4,910,000
$1,299,000
$2,783,000
$1,209,000
$2,591,000

Willett Pond Dam, Norwood/Walpole, Massachusetts
13
Date of Inspection: June 6, 2017
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 FIGURES
Figure 1.
Figure 2.
Figure 3.
Figure 4.
Figure 5.
Figure 6.
Figure 7.
Figure 8.

Locus Plan
Aerial Photograph
Drainage Area
Downstream Area
Site Sketch (Dam)
Site Sketch (Dike)
Dam Photo (Dam)
Photo Key (Dike)

Willett Pond Dam, Norwood/Walpole, Massachusetts
Date of Inspection: June 6, 2017
Based on DCR Template Version 3, June 2008
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 APPENDIX A
Photographs

Willett Pond Dam, Norwood/Walpole, Massachusetts
Date of Inspection: June 6, 2017
Based on DCR Template Version 3, June 2008
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 Willett Pond Dam   June 14, 2017

Photo 1:

Photo 2:

Overview of dam from downstream

Overview of upstream face from right abutment

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Corres. (HQ)

 Willett Pond Dam   June 14, 2017

Photo 3:

Photo 4:

Overview of upstream face from left abutment

Overview of dam crest from right abutment

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Corres. (HQ)

 Willett Pond Dam   June 14, 2017

Photo 5:

Photo 6:

Overview of dam crest from left abutment

Overview downstream face from right abutment

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Corres. (HQ)

 Willett Pond Dam   June 14, 2017

Photo 7:

Overview of downstream face from left abutment

Photo 8:

Overview of spillway from upstream

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Corres. (HQ)

 Willett Pond Dam   June 14, 2017

Photo 9:

Overview of spillway from downstream

Photo 10: Overview of right training wall

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Corres. (HQ)

 Willett Pond Dam   June 14, 2017

Photo 11: Overview of left training wall

Photo 12: Overview of weir

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Corres. (HQ)

 Willett Pond Dam   June 14, 2017

Photo 13: Overview of stilling basin

Photo 14: Overview of downstream channel

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Corres. (HQ)

 Willett Pond Dam   June 14, 2017

Photo 15: Overview of gatehouse exterior

Photo 16: Overview of gatehouse interior

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Corres. (HQ)

 Willett Pond Dam   June 14, 2017

Photo 17: Overview of knife gate valve operator #1 (note leakage)

Photo 18: Overview of knife gate valve operator #2

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Corres. (HQ)

 Willett Pond Dam   June 14, 2017

Photo 19: Overview of operational stem

Photo 20: Overview of Parshall Flume outlet exterior

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Corres. (HQ)

 Willett Pond Dam   June 14, 2017

Photo 21: Overview of Parshall Flume outlet channel and downstream area

Photo 22: Overview of reservoir

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Corres. (HQ)

 Willett Pond Dam   June 14, 2017

Photo 23: Dike crest facing left abutment

Photo 24: Dike upstream slope facing left abutment

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Corres. (HQ)

 Willett Pond Dam   June 14, 2017

Photo 25: Overview of dike crest

Photo 26: Overview of dike crest

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Corres. (HQ)

 Willett Pond Dam   June 14, 2017

Photo 27: Overview of dike crest

Photo 28: Overview of dike crest

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Corres. (HQ)

 Willett Pond Dam   June 14, 2017

Photo 29: Overview of dike crest

Photo 30: Overview of dike crest

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Corres. (HQ)

 Willett Pond Dam   June 14, 2017

Photo 31: Overview of dike crest

Photo 32: Overview of dike crest

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Corres. (HQ)

 Willett Pond Dam   June 14, 2017

Photo 33: Overview of dike crest

Photo 34: Dike crest facing right abutment

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Corres. (HQ)

 Willett Pond Dam   June 14, 2017

Photo 35: Panoramic view of downstream dam face
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Corres. (HQ)

 APPENDIX B
Inspection Checklist

Willett Pond Dam, Norwood/Walpole, Massachusetts
Date of Inspection: June 6, 2017
Based on DCR Template Version 3, June 2008
\\private\dfs\ProjectData\P2005\1323\A85\Deliverables\Report\MA00169_Willett Pond Dam_Norwood Walpole_20170606.doc

 YES

YES

NO

Dam Safety Inspection Checklist v.3.1

FOLLOW-UP INSPECTION REQUIRED:

2500

1736

YES

142 (dike crest height)

CONDITIONAL LETTER:

EL. MAXIMUM POOL (FT):

20

HYDRAULIC HEIGHT (FT):

139.9

MAXIMUM POOL STORAGE (ACRE-FT):
EL. NORMAL POOL (FT):

FOR INTERNAL MADCR USE ONLY

800

LONG.: 71.233W

NORMAL POOL STORAGE (ACRE-FT):

OVERALL LENGTH (FT):

GENERAL DAM INFORMATION

25

1913

Recreation/Conservation

Earth Embankment

42.1812N

RIVER: Bubbling Brook

LAT.:

ALTERNATE DAM NAME:

COUNTY: Norfolk

STRUCTURAL HEIGHT (FT):

YEAR BUILT:

PURPOSE OF DAM:

TYPE OF DAM:

Willett Pond

Boston Harbor

Norwood

MA00169

NID ID #:
STATE HAZARD CLASSIFICATION:
High
CHANGE IN HAZARD CLASSIFICATION REQUESTED?:

6-11-220-02

STATE ID #:

DAM LOCATION INFORMATION

Brook Street (Norwood), Bullard Street (Walpole)

IMPOUNDMENT NAME(S):

DRAINAGE BASIN:

USGS QUAD.:

DAM LOCATION:
(street address if known)

CITY/TOWN: Norwood

Large

NO

Willett Pond Dam and Dike

STATE SIZE CLASSIFICATION:

REGISTERED:

NAME OF DAM:

DAM SAFETY INSPECTION CHECKLIST

NO

No

Page 1

 MA00169

6-11-220-02

TYPE OF DESIGN
LEVEL OF MAINTENANCE
EMERGENCY ACTION PLAN
EMBANKMENT SEEPAGE
EMBANKMENT CONDITION
CONCRETE CONDITION
LOW-LEVEL OUTLET CAPACITY

Dam Safety Inspection Checklist v.3.1

NAME OF INSPECTING ENGINEER:

E1)
E2)
E3)
E4)
E5)
E6)
E7)

Shawn King

NAME

Chris Cullen

3
4
5
5
4
4
4

YES

YES

120.5

Click on box to select E-code

LOW-LEVEL OUTLET CONDITION
5
SPILLWAY DESIGN FLOOD CAPACITY 1
OVERALL PHYSICAL CONDITION
2
ESTIMATED REPAIR COST
$1,046,900 - $4,910,000
ROADWAY OVER CREST
YES
BRIDGE NEAR DAM
YES

Fuss & O'Neill

SIGNATURE:

E8)
E9)
E10)
E11)

EVALUATION INFORMATION

Project Engineer

TITLE/POSITION

If YES, date 7-Jul-15

If YES, date April, 1979

Fall 2007-Spring 2008

NO

NO

July 7, 2015

REPRESENTING

EL. TAILWATER DURING INSP.:

DATE OF LAST REHABILITATION:

PERSONS PRESENT AT INSPECTION

Click on box to select E-code

0-50% of the SDF or Unknown

SPILLWAY CAPACITY:

EL. POOL DURING INSP.: 140

POOR

OVERALL PHYSICAL
CONDITION OF DAM:

NGVD29

PREVIOUS DCR PHASE I:

CONSULTANT: Fuss & O'Neill, Inc.

BENCHMARK/DATUM:

ARMY CORPS PHASE I:

DATE OF PREVIOUS INSPECTION:

INSPECTION SUMMARY

NID ID #:

STATE ID #:

TEMPERATURE/WEATHER: 85°F, Clear

June 6, 2017

June 6, 2017

DATE OF INSPECTION:

INSPECTION DATE:

NAME OF DAM: Willett Pond Dam and Dike

Page 2

 YES

PUBLIC BRIDGE WITHIN 50' OF DAM?

Dam Safety Inspection Checklist v.3.1

YES

DOES CREST SUPPORT PUBLIC ROAD?

FISH LADDER (LIST TYPE IF PRESENT)

HAS DAM BEEN BREACHED OR OVERTOPPED

4.8
YES

NO

NO

20-inch diameter ductile iron pipes (2)

2

DRAINAGE AREA (SQ MI)

TYPE OF OUTLETS

NUMBER OF OUTLETS

1/2PMF, 4,830

IF YES, ROAD/BRIDGE NAME: Brook St (Norwood) and Bullard st. (Walpole)
BR#W-03-037(3KC)
MHD BRIDGE NO. (IF APPLICABLE)

Brook St (Norwood) and Bullard st. (Walpole)

IF YES, PROVIDE DATE(S)

IF YES, ROAD NAME:

NO

SPILLWAY DESIGN FLOOD (PERIOD/CFS)

346/746 (With/without stop logs)

96 (at max pool)

TOTAL DISCHARGE CAPACITY (CFS)

OUTLET(S) CAPACITY (CFS)

AUX. SPILLWAY CAPACITY (CFS) N/A

N/A

AUXILIARY SPILLWAY TYPE

Neponset River Land Holding Assoc.
Tom Palmer & Ian Cooke
2173 Washington Street
Canton, MA 02021
781-575-0354
978-467-5271
781-575-9971
palmer@neponset.org

250/650 (with/without stop logs)

SPILLWAY CAPACITY (CFS)

28.3

CARETAKER: ORGANIZATION
NAME/TITLE
STREET
TOWN, STATE, ZIP
PHONE
EMERGENCY PH. #
FAX
EMAIL

MA00169

SPILLWAY LENGTH (FT)

Neponset River Land Holding Ass
Ian Cooke, President
2173 Washington Street
Canton, MA 02021
781-575-0354
781-575-0354
781-575-9971
cooke@neponset.org
Private Association or other non-profit

NID ID #:

6-11-220-02

Box Culvert/Channel

ORGANIZATION
NAME/TITLE
STREET
TOWN, STATE, ZIP
PHONE
EMERGENCY PH. #
FAX
EMAIL
OWNER TYPE

June 6, 2017

STATE ID #:

PRIMARY SPILLWAY TYPE

OWNER:

INSPECTION DATE:

NAME OF DAM: Willett Pond Dam and Dike

Page 3

 OBSERVATIONS

Paved Road
1. SURFACE TYPE
Numerous cracks in pavement; patched
2. SURFACE CRACKING
None observed
3. SINKHOLES, ANIMAL BURROWS
4. VERTICAL ALIGNMENT (DEPRESSIONS) Minor - gradual changes along dam crest
Good
5. HORIZONTAL ALIGNMENT
6. RUTS AND/OR PUDDLES
Some rutting of pavement
7. VEGETATION (PRESENCE/CONDITION) Paved road
8. ABUTMENT CONTACT
Good

CONDITION

Dam Safety Inspection Checklist v.3.1

ADDITIONAL COMMENTS: The dam crest cannot be observed because a paved road with base course has been constructed on the original dam crest.

CREST

AREA
INSPECTED

MA00169

6-11-220-02

EMBANKMENT (CREST)

NID ID #:

INSPECTION DATE:

June 6, 2017

STATE ID #:

NAME OF DAM: Willett Pond Dam and Dike

NO
ACTION

X
X
X
X
X
X
X
X

REPAIR

MONITOR

Page 4

 1. WET AREAS (NO FLOW)
2. SEEPAGE
3. SLIDE, SLOUGH, SCARP
4. EMB.-ABUTMENT CONTACT
5. SINKHOLE/ANIMAL BURROWS
6. EROSION
7. UNUSUAL MOVEMENT
8. VEGETATION (PRESENCE/CONDITION)

CONDITION

June 6, 2017

Dam Safety Inspection Checklist v.3.1

ADDITIONAL COMMENTS:

D/S
SLOPE

AREA
INSPECTED

INSPECTION DATE:

NAME OF DAM: Willett Pond Dam and Dike
MA00169

6-11-220-02

Wet areas along significant portion of toe likely due to downstream wetland
None Observed
None Observed
Some stone and misc. fill at the left dam/abutment contact
None Observed
None Observed
None Observed
Good

OBSERVATIONS

EMBANKMENT (D/S SLOPE)

NID ID #:

STATE ID #:

NO
ACTION

X
X
X
X
X
X
X

MONITOR

X

REPAIR

Page 5

 1. SLIDE, SLOUGH, SCARP
2. SLOPE PROTECTION TYPE AND COND.
3. SINKHOLE/ANIMAL BURROWS
4. EMB.-ABUTMENT CONTACT
5. EROSION
6. UNUSUAL MOVEMENT
7. VEGETATION (PRESENCE/CONDITION)

CONDITION

None Observed
Placed rip-rap along upstream face in good condition (see notes)
None Observed
Good
None Observed
None Observed
Riprap, no vegetation

OBSERVATIONS

X
X
X
X
X
X
X

NO
ACTION

Dam Safety Inspection Checklist v.3.1

ADDITIONAL COMMENTS: Flat placed large stones on upstream face. Road crest appears to have been raised by placing fill over original dam crest. This
2' of fill has an irregular edge that may be subject to erosion from wave action. Any erosion would affect the road condition, but
would likely not adversely impact the dam.

U/S
SLOPE

AREA
INSPECTED

MA00169

6-11-220-02

EMBANKMENT (U/S SLOPE)

NID ID #:

INSPECTION DATE:

June 6, 2017

STATE ID #:

NAME OF DAM: Willett Pond Dam and Dike

REPAIR

MONITOR

Page 6

 1. PIEZOMETERS
2. OBSERVATION WELLS
3. STAFF GAGE AND RECORDER
4. WEIRS
5. INCLINOMETERS
6. SURVEY MONUMENTS
7. DRAINS
8. FREQUENCY OF READINGS
9. LOCATION OF READINGS

CONDITION

June 6, 2017

OBSERVATIONS

MA00169

6-11-220-02

2 piezometers were installed along dam crest (up and downstream of internal core wall)
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A

INSTRUMENTATION

NID ID #:

STATE ID #:

Dam Safety Inspection Checklist v.3.1

ADDITIONAL COMMENTS: 2 piezometers were also located on dike near left and right abutments

INSTR.

AREA
INSPECTED

INSPECTION DATE:

NAME OF DAM: Willett Pond Dam and Dike

MONITOR

X

REPAIR

NO
ACTION

Page 7

 CONDITION

1. WALL TYPE
2. WALL ALIGNMENT
3. WALL CONDITION
4. HEIGHT: TOP OF WALL TO MUDLINE
5. SEEPAGE OR LEAKAGE
6. ABUTMENT CONTACT
7. EROSION/SINKHOLES BEHIND WALL
8. ANIMAL BURROWS
9. UNUSUAL MOVEMENT
10. WET AREAS AT TOE OF WALL

Dam Safety Inspection Checklist v.3.1

ADDITIONAL COMMENTS:

D/S WALLS

AREA
INSPECTED

MA00169

6-11-220-02

N/A
N/A
N/A
min:
N/A
N/A
N/A
N/A
N/A
N/A
max:

OBSERVATIONS

DOWNSTREAM MASONRY WALLS

NID ID #:

INSPECTION DATE:

June 6, 2017

STATE ID #:

NAME OF DAM: Willett Pond Dam and Dike

avg:

REPAIR

MONITOR
NO
ACTION

Page 8

 1. WALL TYPE
2. WALL ALIGNMENT
3. WALL CONDITION
4. HEIGHT: TOP OF WALL TO MUDLINE
5. ABUTMENT CONTACT
6. EROSION/SINKHOLES BEHIND WALL
7. ANIMAL BURROWS
8. UNUSUAL MOVEMENT

CONDITION

June 6, 2017

Dam Safety Inspection Checklist v.3.1

ADDITIONAL COMMENTS:

U/S WALLS

AREA
INSPECTED

INSPECTION DATE:

NAME OF DAM: Willett Pond Dam and Dike
MA00169

6-11-220-02

N/A
N/A
N/A
min:
N/A
N/A
N/A
N/A
max:

OBSERVATIONS

UPSTREAM MASONRY WALLS

NID ID #:

STATE ID #:

avg:

REPAIR

MONITOR
NO
ACTION

Page 9

 OBSERVATIONS

MA00169

6-11-220-02

None Observed
None Observed
None Observed
None Observed
None Observed
Parshall Flume Downstream of Gate House
Heavy vegetation, lots of brush
No ready access, except by foot

DOWNSTREAM AREA

NID ID #:

STATE ID #:

10. DATE OF LAST EAP UPDATE

9. DOWNSTREAM HAZARD DESCRIPTION Developed residential with some industrial and commercial

1. ABUTMENT LEAKAGE
2. FOUNDATION SEEPAGE
3. SLIDE, SLOUGH, SCARP
4. WEIRS
5. DRAINAGE SYSTEM
6. INSTRUMENTATION
7. VEGETATION
8. ACCESSIBILITY

CONDITION

June 6, 2017

Dam Safety Inspection Checklist v.3.1

ADDITIONAL COMMENTS:

D/S
AREA

AREA
INSPECTED

INSPECTION DATE:

NAME OF DAM: Willett Pond Dam and Dike

3/17/2016

NO
ACTION

X
X
X
X
X
X
X
X

REPAIR

MONITOR

Page 10

 Bullard Street in Walpole, Brook street in Norwood
Gate house is triple locked
WHAT:
YES
NO
DATE:
YES
NO
DATE:
YES
NO
DATE:
YES
NO
DATE:
YES
NO
DATE:
YES
NO
PURPOSE:
YES
NO

4. ACCESS ROADS
5. SECURITY DEVICES
6. VANDALISM OR TRESPASS
7. AVAILABILITY OF PLANS
8. AVAILABILITY OF DESIGN CALCS
9. AVAILABILITY OF EAP/LAST UPDATE
10. AVAILABILITY OF O&M MANUAL
11. CARETAKER/OWNER AVAILABLE
12. CONFINED SPACE ENTRY REQUIRED

ty Inspection Checklist v.3.1

ACOE Phase 1 - April 1979
ACOE Phase 1 - April 1979
3/17/2016
June 4, 2013
June 6, 2017

OBSERVATIONS

MA00169

6-11-220-02

Unknown
Private residences, primarily. Some undeveloped
Mild to moderate

MISCELLANEOUS

NID ID #:

STATE ID #:

1. RESERVOIR DEPTH (AVG)
2. RESERVOIR SHORELINE
3. RESERVOIR SLOPES

CONDITION

June 6, 2017

ADDITIONAL COMMENTS: EAP was updated in 2016

MISC.

AREA
INSPECTED

INSPECTION DATE:

NAME OF DAM: Willett Pond Dam and Dike

Page 11

 SPILLWAY TYPE
WEIR TYPE
SPILLWAY CONDITION
TRAINING WALLS
SPILLWAY CONTROLS AND CONDITION
UNUSUAL MOVEMENT
APPROACH AREA
DISCHARGE AREA
DEBRIS
WATER LEVEL AT TIME OF INSPECTION

CONDITION

June 6, 2017

Dam Safety Inspection Checklist v.3.1

NID ID #:

X
X
X
X
X
X
X
X
X
X

Concrete channel with vertical side walls
2 ft high stop logs
Fair
Good
Wooden stop logs
None observed
Willet Pond - clear of debris
Stone lined channel, some concrete paving of channel
None observed
Approximately 1" of flow over stop-logs el. 140.0 feet

MA00169

6-11-220-02

OBSERVATIONS

PRIMARY SPILLWAY

ADDITIONAL COMMENTS: Spillway is undersized to pass the SDF

SPILLWAY

AREA
INSPECTED

INSPECTION DATE:

STATE ID #:

NO
ACTION

NAME OF DAM: Willett Pond Dam and Dike

Page 12

REPAIR

MONITOR

 CONDITION

SPILLWAY TYPE
WEIR TYPE
SPILLWAY CONDITION
TRAINING WALLS
SPILLWAY CONTROLS AND CONDITION
UNUSUAL MOVEMENT
APPROACH AREA
DISCHARGE AREA
DEBRIS
WATER LEVEL AT TIME OF INSPECTION

Dam Safety Inspection Checklist v.3.1

ADDITIONAL COMMENTS:

SPILLWAY

AREA
INSPECTED

MA00169

6-11-220-02

N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A

OBSERVATIONS

AUXILIARY SPILLWAY

NID ID #:

INSPECTION DATE:
June 6, 2017

STATE ID #:

NAME OF DAM: Willett Pond Dam and Dike

Page 13

REPAIR

MONITOR
NO
ACTION

 MISCELLANEOUS

TYPE
INTAKE STRUCTURE
TRASHRACK
PRIMARY CLOSURE
SECONDARY CLOSURE
CONDUIT
OUTLET STRUCTURE/HEADWALL
EROSION ALONG TOE OF DAM
SEEPAGE/LEAKAGE
DEBRIS/BLOCKAGE
UNUSUAL MOVEMENT
DOWNSTREAM AREA

CONDITION

June 6, 2017

OBSERVATIONS

MA00169

6-11-220-02

Two 20-inch ductile iron pipes
Submerged, not visible
Unknown
Gate valves located within gate house near downstream toe, minor leakage
N/A
Two 20-inch ductile iron pipes
Discharge to concrete Parshall flume
None observed
Minor leakage from gate valve housings
None observed
None observed
Heavily vegetated stream discharging to a small pond on Hawes brook

OUTLET WORKS

NID ID #:

STATE ID #:

X
X
X

X
X
X
X

X
X
X

NO
ACTION

Dam Safety Inspection Checklist v.3.1

ADDITIONAL COMMENTS: Sump pipe from gate house to the downstream wetland is broken inside the concrete chamber upstream of the Parshall Flume,
allowing water in the flume to back up into the gate house. Temporary repair of pipe has been perfomed by NHLA

OUTLET
WORKS

AREA
INSPECTED

INSPECTION DATE:

NAME OF DAM: Willett Pond Dam and Dike

MONITOR

X

X

REPAIR

Page 14

 TYPE
AVAILABILITY OF PLANS
AVAILABILITY OF DESIGN CALCS
PIEZOMETERS
OBSERVATION WELLS
INCLINOMETERS
SEEPAGE GALLERY
UNUSUAL MOVEMENT

CONDITION

June 6, 2017

Dam Safety Inspection Checklist v.3.1

ADDITIONAL COMMENTS:

GENERAL

AREA
INSPECTED

INSPECTION DATE:

NAME OF DAM: Willett Pond Dam and Dike
MA00169

6-11-220-02

N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A

OBSERVATIONS

CONCRETE/MASONRY DAMS

NID ID #:

STATE ID #:

REPAIR

MONITOR
NO
ACTION

Page 15

 TYPE
SURFACE CONDITIONS
CONDITIONS OF JOINTS
UNUSUAL MOVEMENT
HORIZONTAL ALIGNMENT
VERTICAL ALIGNMENT

CONDITION

June 6, 2017

Dam Safety Inspection Checklist v.3.1

ADDITIONAL COMMENTS:

CREST

AREA
INSPECTED

INSPECTION DATE:

NAME OF DAM: Willett Pond Dam and Dike
MA00169

6-11-220-02

N/A
N/A
N/A
N/A
N/A
N/A

OBSERVATIONS

CONCRETE/MASONRY DAMS (CREST)

NID ID #:

STATE ID #:

REPAIR

MONITOR
NO
ACTION

Page 16

 TYPE
SURFACE CONDITIONS
CONDITIONS OF JOINTS
UNUSUAL MOVEMENT
ABUTMENT CONTACT
LEAKAGE

Dam Safety Inspection Checklist v.3.1

NID ID #:

STATE ID #:
MA00169

6-11-220-02

N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A

OBSERVATIONS

CONCRETE/MASONRY DAMS (DOWNSTREAM FACE)
CONDITION

June 6, 2017

ADDITIONAL COMMENTS:

D/S
FACE

AREA
INSPECTED

INSPECTION DATE:

NAME OF DAM: Willett Pond Dam and Dike

REPAIR

MONITOR
NO
ACTION

Page 17

 TYPE
SURFACE CONDITIONS
CONDITIONS OF JOINTS
UNUSUAL MOVEMENT
ABUTMENT CONTACTS

CONDITION

June 6, 2017

Dam Safety Inspection Checklist v.3.1

ADDITIONAL COMMENTS:

U/S
FACE

AREA
INSPECTED

INSPECTION DATE:

NAME OF DAM: Willett Pond Dam and Dike
MA00169

6-11-220-02

N/A
N/A
N/A
N/A
N/A

OBSERVATIONS

CONCRETE/MASONRY DAMS (UPSTREAM FACE)

NID ID #:

STATE ID #:

REPAIR

MONITOR
NO
ACTION

Page 8

 MA00169

OBSERVATIONS

DIKE EMBANKMENT (CREST)

NID ID #:

6-11-220-02

1. SURFACE TYPE
Irregular Vegetation, see note
None observed
2. SURFACE CRACKING
None observed
3. SINKHOLES, ANIMAL BURROWS
4. VERTICAL ALIGNMENT (DEPRESSIONS) Minor undulations of crest along 1,900-foot length ranging from 142' to 143'
5. HORIZONTAL ALIGNMENT
Good.
6. RUTS AND/OR PUDDLES
None Observed
7. VEGETATION (PRESENCE/CONDITION) Some small trees (birch, small evergreens) on upstream face near waters edge.
Good
8. ABUTMENT CONTACT

CONDITION

June 6, 2017

STATE ID #:

Dam Safety Inspection Checklist v.3.1

ADDITIONAL COMMENTS: Varied including well maintained grass; some previous bare areas being revegetated

CREST

AREA
INSPECTED

INSPECTION DATE:

NAME OF DAM: Willett Pond Dam and Dike

NO
ACTION

X

X

MONITOR

X
X

X
X
X

X

REPAIR

Page 4

 NID ID #:

MA00169

6-11-220-02

None observed
None Observed
None Observed
Good
None Observed
None Observed
None Observed
Irregular grass cover (see comments below)

OBSERVATIONS

DIKE EMBANKMENT (D/S SLOPE)

1. WET AREAS (NO FLOW)
2. SEEPAGE
3. SLIDE, SLOUGH, SCARP
4. EMB.-ABUTMENT CONTACT
5. SINKHOLE/ANIMAL BURROWS
6. EROSION
7. UNUSUAL MOVEMENT
8. VEGETATION (PRESENCE/CONDITION)

CONDITION

June 6, 2017

STATE ID #:

Dam Safety Inspection Checklist v.3.1

ADDITIONAL COMMENTS: Varied including well maintained grass, areas of recently removed woody vegetation (wood chips), some bare/sandy areas
Water collects in swales along the dowstream dike toe. These swales outlet toward the road periodically.

D/S
SLOPE

AREA
INSPECTED

INSPECTION DATE:

NAME OF DAM: Willett Pond Dam and Dike

NO
ACTION

X
X
X
X
X
X
X
X

REPAIR

MONITOR

Page 5

 CONDITION

1. SLIDE, SLOUGH, SCARP
2. SLOPE PROTECTION TYPE AND COND.
3. SINKHOLE/ANIMAL BURROWS
4. EMB.-ABUTMENT CONTACT
5. EROSION
6. UNUSUAL MOVEMENT
7. VEGETATION (PRESENCE/CONDITION)

Dam Safety Inspection Checklist v.3.1

ADDITIONAL COMMENTS:

U/S
SLOPE

AREA
INSPECTED

MA00169

6-11-220-02

None Observed
Placed rip-rap along majority of dike
None Observed
Good
Some areas worn, possibly due to pedestrian traffic
None Observed
Small trees and bushes along upstream face near water level

OBSERVATIONS

DIKE EMBANKMENT (U/S SLOPE)

NID ID #:

INSPECTION DATE:

June 6, 2017

STATE ID #:

NAME OF DAM: Willett Pond Dam and Dike

NO
ACTION

X

X
X
X
X

X

X

REPAIR

MONITOR

Page 6

 CONDITION

1. PIEZOMETERS
2. OBSERVATION WELLS
3. STAFF GAGE AND RECORDER
4. WEIRS
5. INCLINOMETERS
6. SURVEY MONUMENTS
7. DRAINS
8. FREQUENCY OF READINGS
9. LOCATION OF READINGS

Dam Safety Inspection Checklist v.3.1

ADDITIONAL COMMENTS:

INSTR.

AREA
INSPECTED

MA00169

6-11-220-02

2 piezometers were installed along dike crest. Located near the abutments
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A

OBSERVATIONS

DIKE INSTRUMENTATION

NID ID #:

INSPECTION DATE:
June 6, 2017

STATE ID #:

NAME OF DAM: Willett Pond Dam and Dike

MONITOR

X

REPAIR

NO
ACTION

Page 7

 10. DATE OF LAST EAP UPDATE

Dam Safety Inspection Checklist v.3.1

3/17/2016

None Observed
None Observed
None Observed
None Observed
None Observed
None Observed
Ranges from lawn areas to wooded lots
Accessible from easement at north end of dike; also through select residence yards
with permission

OBSERVATIONS

9. DOWNSTREAM HAZARD DESCRIPTION Houses generally set back 100 feet to 300+ feet from dike

1. ABUTMENT LEAKAGE
2. FOUNDATION SEEPAGE
3. SLIDE, SLOUGH, SCARP
4. WEIRS
5. DRAINAGE SYSTEM
6. INSTRUMENTATION
7. VEGETATION
8. ACCESSIBILITY

CONDITION

ADDITIONAL COMMENTS: Generally residential development down stream of the dike.

D/S
AREA

AREA
INSPECTED

MA00169

6-11-220-02

DIKE DOWNSTREAM AREA

NID ID #:

INSPECTION DATE:
June 6, 2017

STATE ID #:

NAME OF DAM: Willett Pond Dam and Dike

NO
ACTION

X
X
X
X
X
X
X
X

REPAIR

MONITOR

Page 10

 Unknown
Private residences. Some undeveloped
Mild to moderate
Bullard Street in Walpole, Brook street in Norwood
NA
WHAT:
YES
NO
DATE:
YES
NO
DATE:
YES
NO
DATE:
YES
NO
DATE:
YES
NO
DATE:
YES
NO
PURPOSE:
YES
NO

4. ACCESS ROADS
5. SECURITY DEVICES
6. VANDALISM OR TRESPASS
7. AVAILABILITY OF PLANS
8. AVAILABILITY OF DESIGN CALCS
9. AVAILABILITY OF EAP/LAST UPDATE
10. AVAILABILITY OF O&M MANUAL
11. CARETAKER/OWNER AVAILABLE
12. CONFINED SPACE ENTRY REQUIRED

ACOE Phase 1 - April 1979
ACOE Phase 1 - April 1979
3/1/2016
June 4, 2013
June 6, 2017

OBSERVATIONS

MA00169

DIKE MISCELLANEOUS

NID ID #:

6-11-220-02

1. RESERVOIR DEPTH (AVG)
2. RESERVOIR SHORELINE
3. RESERVOIR SLOPES

CONDITION

June 6, 2017

STATE ID #:

ty Inspection Checklist v.3.1

ADDITIONAL COMMENTS: Home owners use the dike for access to Lake. They generally mow grass and in some cases have planted shrubs/flower beds.

MISC.

AREA
INSPECTED

INSPECTION DATE:

NAME OF DAM: Willett Pond Dam and Dike

Page 11

 APPENDIX C
Previous Reports and References

Willett Pond Dam, Norwood/Walpole, Massachusetts
Date of Inspection: June 6, 2017
Based on DCR Template Version 3, June 2008
\\private\dfs\ProjectData\P2005\1323\A85\Deliverables\Report\MA00169_Willett Pond Dam_Norwood Walpole_20170606.doc

 PREVIOUS REPORTS AND REFERENCES
The following is a list of reports that were located during the file review, or were referenced in
previous reports.
1. Inspection plans for Army Corps of Engineers, prepared by Metcalf & Eddy, Inc., 1979.
2. “Willett Pond Dam, Inspection/Evaluation and Hydraulic/Hydrologic Report,”
prepared by PARE Engineering, September 2005.
3. “Willett Pond Dam, Phase I Inspection/Evaluation Report,” Prepared by GZA
GeoEnvironmental, Inc., June 2007.
4. “Operation and Maintenance Plan, Willett Pond Dam and Dike,
Dam ID# 6-11-220-02, Army Corp ID# MA0016 Norwood/Walpole, Massachusetts,”
prepared by NRLHA, Norwood, MA.
5. “Willett pond Dam, 90-Day Follow-up Inspection/Evaluation Report,” prepared by
Fuss & O’Neill, Inc, January 2008.
6. “Willett Pond Dam, Inspection/Evaluation Report,” prepared by Fuss & O’Neill, June
11, 2009.
7. “Willett Pond Dam, Inspection/Evaluation Report,” prepared by Fuss & O’Neill, June
22, 2011.
8. “Willett Pond Dam, Phase II Investigation Final Report,” prepared by Fuss & O’Neill,
Inc., dated July 29, 2011.
9. “Willett Pond Dam, Phase I Inspection/Evaluation Report,” prepared by Fuss &
O’Neill Inc., dated June 4, 2013.
10. “Willett Pond Dam, Phase I Inspection/Evaluation Report,” prepared by Fuss &
O’Neill Inc., dated July 7, 2015.
The following references were utilized during the preparation of this report and the
development of the recommendations presented herein.
1. “Estimating Peak Discharges of Small, Rural Streams in Massachusetts” (Water Supply
Paper 2214), U.S. Geological Survey, Alexandria, VA, 1983.
2. “Recommended Guidelines for Safety Inspection of Dams” (ER 1110-2-106 – National
Program of Inspection of Dams, Volume I, Appendix D), U.S. Army Corps of
Engineers, Washington, DC, 1976.
3. “Technical Paper No. 40, Rainfall Frequency Atlas of the United States for Durations
from 30 Minutes to 24 Hours and Return Periods from 1 to 100 Years”, US Dept. of
Commerce Weather Bureau, Washington, DC, May 1961.

Willett Pond Dam, Norwood/Walpole, Massachusetts
Date of Inspection: June 6, 2017
Based on DCR Template Version 3, June 2008
\\private\dfs\ProjectData\P2005\1323\A85\Deliverables\Report\MA00169_Willett Pond Dam_Norwood Walpole_20170606.doc

 APPENDIX D
Definitions

Willett Pond Dam, Norwood/Walpole, Massachusetts
Date of Inspection: June 6, 2017
Based on DCR Template Version 3, June 2008
\\private\dfs\ProjectData\P2005\1323\A85\Deliverables\Report\MA00169_Willett Pond Dam_Norwood Walpole_20170606.doc

 COMMON DAM SAFETY DEFINITIONS
For a comprehensive list of dam engineering terminology and definitions refer to 302 CMR10.00 Dam
Safety, or other reference published by FERC, Dept. of the Interior Bureau of Reclamation, or FEMA.
Please note should discrepancies between definitions exist, those definitions included within 302 CMR
10.00 govern for dams located within the Commonwealth of Massachusetts.
Orientation
Upstream – Shall mean the side of the dam that borders the impoundment.
Downstream – Shall mean the high side of the dam, the side opposite the upstream side.
Right – Shall mean the area to the right when looking in the downstream direction.
Left – Shall mean the area to the left when looking in the downstream direction.
Dam Components
Dam – Shall mean any artificial barrier, including appurtenant works, which impounds or diverts water.
Embankment – Shall mean the fill material, usually earth or rock, placed with sloping sides, such that it
forms a permanent barrier that impounds water.
Crest – Shall mean the top of the dam, usually provides a road or path across the dam.
Abutment – Shall mean that part of a valley side against which a dam is constructed. An artificial
abutment is sometimes constructed as a concrete gravity section, to take the thrust of an arch dam where
there is no suitable natural abutment.
Appurtenant Works – Shall mean structures, either in dams or separate therefrom, including but not be
limited to, spillways; reservoirs and their rims; low-level outlet works; and water conduits including
tunnels, pipelines, or penstocks, either through the dams or their abutments.
Spillway – Shall mean a structure over or through which water flows are discharged. If the flow is
controlled by gates or boards, it is a controlled spillway; if the fixed elevation of the spillway crest
controls the level of the impoundment, it is an uncontrolled spillway.
Size Classification
(as listed in Commonwealth of Massachusetts, 302 CMR 10.00 Dam Safety)
Large – structure with a height greater than 40 feet or a storage capacity greater than 1,000 acre-feet.
Intermediate – structure with a height between 15 and 40 feet or a storage capacity of 50 to 1,000 acrefeet.
Small – structure with a height between 6 and 15 feet and a storage capacity of 15 to 50 acre-feet.
Non-Jurisdictional – structure less than 6 feet in height or having a storage capacity of less than 15 acrefeet.
Willett Pond Dam, Norwood/Walpole, Massachusetts
Date of Inspection: June 6, 2017
Based on DCR Template Version 3, June 2008
\\private\dfs\ProjectData\P2005\1323\A85\Deliverables\Report\MA00169_Willett Pond Dam_Norwood Walpole_20170606.doc

 Hazard Classification
(as listed in Commonwealth of Massachusetts, 302 CMR 10.00 Dam Safety)
High Hazard (Class I) – Shall mean dams located where failure will likely cause loss of life and serious
damage to home(s), industrial or commercial facilities, important public utilities, main highway(s) or
railroad(s).
Significant Hazard (Class II) – Shall mean dams located where failure may cause loss of life and damage
to home(s), industrial or commercial facilities, secondary highway(s) or railroad(s), or cause the
interruption of the use or service of relatively important facilities.
Low Hazard (Class III) – Dams located where failure may cause minimal property damage to others.
Loss of life is not expected.
General
EAP – Emergency Action Plan – Shall mean a predetermined (and properly documented) plan of action
to be taken to reduce the potential for property damage and/or loss of life in an area affected by an
impending dam failure.
O&M Manual – Operations and Maintenance Manual; Document identifying routine maintenance and
operational procedures under normal and storm conditions.
Normal Pool – Shall mean the elevation of the impoundment during normal operating conditions.
Acre-foot – Shall mean a unit of volumetric measure that would cover one acre to a depth of one foot.
It is equal to 43,560 cubic feet. One million U.S. gallons = 3.068 acre feet.
Height of Dam (Structural Height) – Shall mean the vertical distance from the lowest portion of the
natural ground, including any stream channel, along the downstream toe of the dam to the lowest point
on the crest of the dam.
Hydraulic Height – means the height to which water rises behind a dam and the difference between the
lowest point in the original streambed at the axis of the dam and the maximum controllable water
surface.
Maximum Water Storage Elevation – means the maximum elevation of water surface which can be
contained by the dam without overtopping the embankment section.
Spillway Design Flood (SDF) – Shall mean the flood used in the design of a dam and its appurtenant
works particularly for sizing the spillway and outlet works, and for determining maximum temporary
storage and height of dam requirements.
Maximum Storage Capacity – The volume of water contained in the impoundment at maximum water
storage elevation.
Normal Storage Capacity – The volume of water contained in the impoundment at normal water storage
elevation.

Willett Pond Dam, Norwood/Walpole, Massachusetts
Date of Inspection: June 6, 2017
Based on DCR Template Version 3, June 2008
\\private\dfs\ProjectData\P2005\1323\A85\Deliverables\Report\MA00169_Willett Pond Dam_Norwood Walpole_20170606.doc

 Condition Rating
Unsafe – Major structural*, operational, and maintenance deficiencies exist under normal operating
conditions.
Poor – Significant structural*, operation and maintenance deficiencies are clearly recognized for normal
loading conditions.
Fair – Significant operational and maintenance deficiencies, no structural deficiencies. Potential
deficiencies exist under unusual loading conditions that may realistically occur. Can be used when
uncertainties exist as to critical parameters.
Satisfactory – Minor operational and maintenance deficiencies. Infrequent hydrologic events would
probably result in deficiencies.
Good – No existing or potential deficiencies recognized. Safe performance is expected under all loading
including SDF.
* Structural deficiencies include but are not limited to the following:
x
x
x
x
x
x

Excessive uncontrolled seepage (e.g., upwelling of water, evidence of fines movement, flowing
water, erosion, etc.)
Missing riprap with resulting erosion of slope
Sinkholes, particularly behind retaining walls and above outlet pipes, possibly indicating loss of
soil due to piping, rather than animal burrows
Excessive vegetation and tree growth, particularly if it obscures features of the dam and the dam
cannot be fully inspected
Deterioration of concrete structures (e.g., exposed rebar, tilted walls, large cracks with or without
seepage, excessive spalling, etc.)
Inoperable outlets (gates and valves that have not been operated for many years or are broken)

Willett Pond Dam, Norwood/Walpole, Massachusetts
Date of Inspection: June 6, 2017
Based on DCR Template Version 3, June 2008
\\private\dfs\ProjectData\P2005\1323\A85\Deliverables\Report\MA00169_Willett Pond Dam_Norwood Walpole_20170606.doc