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LOWER THAMES RIVER BASIN

NORWICH, CONNECTICUT

r TRADING COVEPOND DAMCT 00237

PHASE 1 INSPECTION REPORTNAT4ONAL-DAM 4N-SEC-TI4fIPROGRAM-

aFu OMj S

DEPARTMENT OF THE ARMYNEW ENGLAND DIVISION, CORPS OF ENGINEERS

WALTHAM, MASS.

JUNE 1081

thx.* Lbu

tI NCIr I E I I'DSECURITY CLASSIFICAtION OF THIS PAGE lWhen Dees, nteed)

REPORT DOCUMENTATION PAGE READ INSTRUCTIONSBEFORE COMPLETING FORM

1. REPORT NUMBER 2. GOVT ACCESSION NO. ,. RECIPIENT"S CATALOG NUMBER

CT_00237 1________ ________1

4. TITLE fend Subil/e) 5 TYPE OF REPORT A PERIOD COVEREO

Trading Cove Pond Dam INSPECTION REPORT

NATIONAL PROGRAM FOR INSPECTION OF NON-FEDERAL PERFORMINGORO. REPORT NUMBER

DAMS -_________________7. AUTHORI.) S. CONTRACT OR GRANT NUUMBER(e)

U.S. ARMY CORPS OF ENGINEERSNEW ENGLAND DIVISION9. PERFORMING ORGANIZATION NAME AND AORE 10. PRORA' LLEMENT. PROJCT, TASK

ARFA A WORK UNIT NUMBERS

| CONTROLLING OFFICE NA4E AND ADDRESS 12. RBPONT DATS

DEPT. OF THE ARMY, CORPS OF ENGINEERS June 1981NEW ENGLAND DIVISION, NEDED ,,. NUmER OF PAGES424 TRAPELO ROAD, WALTHAM, MA. 02254 5014. MONITORING AGENCY NAMEz & ADDRESS(It dillteanl from Cot /ian OI1ice) IS. SECURITY CLASS. (at shl. report)

UNCLASSIFIED6I0. DECLA IIC ATION/DOWNGRAoiNG

SCHEDULE

IS. DISTRIBUTION STATEMENT (of this *epope')

APPROVAL FOR PUBLIC RELEASE: DISTRIBUTION UNLIMITED

I?. DISTRIBUTION STATEMENT (of the . otct enteed in Mack' .0. IIt. iffo.ent fro.m Sepot)

It. SUPPLEMENTARY NOYES

Cover program reads: Phase I Inspection Report, National Dam Inspection Program;however, the official title of the program is: National Program for Inspection ofNon-Federal Dams; use cover date for date of report.

It. KEY WORDS (Conin~eue on~ rovoroe side It R066084107 And 1910"#14 6V WO.,e number)

DAMS, INSPECTION, DAM SAFETY,Lower Thames River BasinNorwich, Conn.

20 AUSTRACT (Coni.nue on .eee aide It nece..ty nd Ifdtitr ky Jl ,c At,,*,)

Trading Cove Dam is an earth embankmcnt dan with vertical masonry walls along theupstream crest. The dam is 230 feet long and 29 feet high as measure d above thestream bed. As a result of the visual inspection and hydrolo.ic and hvdr. uIi"compu tat ions, the dni i,; considered to he in FAIR ond it ion. 11c d;u, ii ,l ;i.s.i'iedas SMALL in size and as having a O,1, halvza ( potential, in a'Cord.iiics, wiL tIi t. r .'' . -f-,nded guidclines established by the Corps ,f Eng ineers. lhi storaoe c~yacit V

at the tnp of the dIor i:; 500 acre feet.

DO I DAN ,7 1471 IOIT1.0 0, 1 NOV 05 1 OBSOLETE

Accession For

'~NTIS G7?A&INATIONAL DAM INSPECTION PROGRAM DTIC TAB

Unannounced [PHASE I INSPECTION REPORT Justification 0

Name of Dam: Trading Cove Pond Dam ByDistri~utiton/

Identification No.: CT 00237 Avaiiaility Cedes

i":, i :'Y. /Or S

Town: Norwich and Montville 1 0

County and State: New London, Connecticut

Stream: Trading Cove

Owner: Daniel Griffin & State of 0

Connecticut

Date of Inspection: 8 April 1981

BRIEF ASSESSMENT 0

Trading Cove Dam is an earth embankment dam with verticalmasonry walls along the upstream crest. State Route 32runs along this crest, which is 54 feet wide. The dam is230 feet long and 29 feet high as measured above the streambed. Along the upstream side of the crest there is a 0masonry wall on both sides of the spillway, varying in bothlength and height. From the base of these walls the earthembankment slopes down to the water line established by thecrest elevation of the spillway. The spillway, which is lo-cated near the approximate center of the dam, discharges itsflow directly into a culvert which passes through the dam.The distance from the spillway crest to the entrance of theculvert is about 3 feet. The culvert consists of a concretebox and masonry structure which is 16 feet wide and 15.5feet high.

The outlet works, located near the left abutment of the dam, 0consists of a square concrete opening from which the gratehas been removed. There is no controlling gate mechanismfor this outlet and its discharge point on the downstreamslope of the dam has been blocked by riprap. Some waterstill passes through this opening and is then dischargedinto a tail race channel. The end of the channel has beenblocked but a small opening in the tail race wall providesan outlet to the streambed near the downstream toe of thedam.

The dam presently serves no purpose other than to providea means of crossing Trading Cove Brook with State Route 32

0

which passes over the crest of the dam. Very little isknown about the history of the dam, other than the factthan a downstream mill, which was demolished in 1976, prob-ably used the dam for the generation of mechanical power.It is apparent from the concrete construction within theculvert that when Route 32 was widened to support aboutfour lanes of traffic, the dam was expanded by additionson both the upstream and downstream sides.

As a result of the visual inspection and hydrologic and hy-draulic computations, the dam is considered to be in FAIRcondition. To assure the long term performance of thisstructure, a few items of concern require attention. Theerosion of the downstream slope near the spillway wallsmust be repaired, tree and brush growth on both slopesmust be cleared, the upstream wall should be regrouted anda trash rack and gate mechanism should be installed at theoutlet structure.

The dam is classified as SMALL in size and as having a LOWhazard potential, in accordance with the recommended guide-lines established by the Corps of Engineers. The storagecapacity at the top of the dam is 500 acre feet.

g The test flood for this dam is the 100-year flood, whichfor purposes of calculation has been approximated by 25%of the Probable Maximum Flood. This test flood has a peakinflow of 4,800 cfs and an outflow discharge of 4,500 cfs.The maximum outflow capacity of the spillway before over-topping occurs is 2,300 cfs, which represents approximately51 percent of the test flood outflow.It should be noted that during the final rpview process the

hazard classification for Trading Cove Pond Dam was changedfrom high to low. For this reason, the report is basicallycomplete.

L

LENARD & DILAJ ENGINEERING, INC.

o F. Lenard, P President

Michae Dilaj, P.E., Vice residentProject Manager

PREFACE

This repor,: ..s prepared under guidance contained in the RecommendedGuidelines Zor Safety Inspection of Dams, for Phase I Investiga-tions. Co.i.es of these guidelines may be obtained from the Officeof Chief c Engineers, Washington, D.C. 20314. The purpose of aPhase I Investigation is to identify expeditiously those damswhich may pose hazards to human life or property. The assessmentof the general condition of the dam is based upon available dataand visual ins:ections. Detailed investigations, and analysesinvolving topographic mapping, subsurface investigations, test-ing, and detailed computational evaluations are beyond the scopeof a Phase I Investigation. However, the investigation is in-tended to identify any need for such studies.

In reviewing this report, it should be realized that the reportedcondition of the dam is based on observations of field conditionsat the time of inspection along with data available to the inspec-tion team. In cases where the reservoir was lowered or drainedprior to inspection, such action, while improving the stabilityand safety of the dam, removes the normal load on the structureand may obscure certain conditions which might otherwise be de-tectable if inspected under the normal operating environment ofthe structure.

It is important to note that the condition of a dam depends onnumerous and constantly changing internal and external conditions,and is evolutionary in nature. It would be incorrect to assumethat the present condition of the dam will continue to representthe condition of the dam at some point in the future. Onlythrough continued care and inspection can there be any chancethat unsafe conditions will be detected.

Phase I inspections are not intended to provide detailed hydro-logic and hydraulic analyses. In accordance with the establishedGuidelines, the spillway test flood is based on the estimated"Probable Maximum Flood" for the region (greatest reasonablypossible storm runoff), or fractions thereof. Because of themagnitude and rarity of such a storm event, a finding that aspillway will not pass the test flood should not be interpretedas necessarily posing a highly inadequate condition. The testflood provides a measure of relative need for more detailed hy-drologic and hydraulic studies, considering the size of the dam,its general condition and downstream damage potential.

The Phase I Investigation does not include an assessment of theneed for fences, gates, no-trespassing signs, repairs to exist-ing fences and railings and other items which may be needed tominimize trespass and provide greater security for the facilityand safety to the public. An evaluation of the project for com-pliance with OSHA rules and regulations is also excluded.

TABLE OF CONTENTS

Page No.

LETTER OF TRANSMITTAL

LBRIEF ASSESSMENTUREVIEW BOARD PAGE

PREFACE

TABLE OF CONTENTS

OVERVIEW PHOTO v

LOCATION MAP vi

REPORT

SECTION 1 - PROJECT INFORMATION

1.1 General

a. Authorityb. Purpose of Inspection Program

c. Scope of Inspection Program

1.2 Description of Project 2

a. Locationj b. Description of Dam and Appurtenancesc. Size Classificationd. Hazard Classificatione. Ownershipf. Operatorg. Purpose of Damh. Design and Construction Historyi. Normal Operational Procedure

I 1,3 Pertinent Data 4

a. Drainageb. Discharge at Dam Sitec. Elevationsd. Reservoir Lengthe. Storagef. Reservoir Surface Areag. Damh. Diversion and Regulating Tunneli. Spillwayj. Regulating Outlet

L I0Ii

Page No.

* SECTION 2 - ENGINEERING DATA

2.1 Design 8

2.2 Construction 8

2.3 Operation 8

2.4 Evaluation 8

a. Availabilityb. Adequacy1c. Validity

SECTION 3 - VISUAL INSPECTION

3.1 Findings 9

a. Generalb. Damc. Appurtenant Structuresd. Reservoir Areae. Downstream Channel

3.2 Evaluation 11

SECTION 4 - OPERATIONAL AND MAINTENANCE

PROCEDURES

[ 4.1 Operational Procedures 12

a. Generalb. Description of any Warning System

in Effect

4.2 Maintenance Procedures 12

a. Generalb. Operating Facilities

4.3 Evaluation 12

SECTION 5 - EVALUATION HYDRAULICS/HYDROLOGIC FEATURES

E 5.1 General 13

5.2 Design Data 13

5.3 Experience Data 13

~iii

lS

Page No.

5.4 Test Flood Analysis 14

5.5 Dam Failure Analysis 14

SECTION 6 - EVALUATION OF STRUCTURAL STABILITY

6.1 Visual Observation 15

6.2 Design and Construction Data 15

6.3 Post Construction Changes 15

6.4 Seismic Stability 15

SECTION 7 - ASSESSMENT, RECOMMENDATIONS AND

REMEDIAL MEASURES

7.1 Dam Assessment 16

a. Conditionb. Adequacy of Information

APPENDICES

APPENDIX A - INSPECTION CHECKLIST

APPENDIX B - ENGINEERING DATA

APPENDIX C - PHOTOGRAPHS

APPENDIX D - HYDROLOGIC AND HYDRAULIC COMPUTATIONS

APPENDIX T' - INFORMATION AS CONTAINED IN THE NATIONALINVENTORY OF DAMS

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LOCATION MAPTRADING COVE POND DAM

6%.NORWICH, CONNECTICUT

VICIN(TY MAP

v

PHASE I INSPECTION REPORT

SECTION I - PROJECT INFORMATION

1.1 General:

a. Authority: Public Law 92-367, August 8, 1972,authorized the Secretary of the Army, through theCorps of Engineers, to initiate a National Proaramof Dam Inspection throughout the United States.The New England Division of the Corps of Engineershas been assigned the responsibility of supervisingthe inspection of dams within the New England Re-gion. Lenard & Dilaj Engineering, Inc. has beenretained by the New England Division to inspect and

F report on selected dams in the States of ConnecticutL and Rhode Island. Authorization and notice to pro-

ceed were issued to Lenard & Dilaj Engineering, Inc.under a letter of 6 November, 1980 from William E.

SHodgson, Jr., Colonel, Corps of Engineers. ContractNo. DACW33-81-C-0014 has been assigned by the Corpsof Engineers for this work.

b. Purpose of Inspection Program: The purposes of theprogram are to:

1. Perform technical inspection and evaluation ofnon-federal dams to identify conditions requir-ing correction in a timely manner by non-federalinterest.

2. Encourage and prepare the states to quickly ini-tiate effective dam inspection programs for non-federal dams.

F 3. To update, verify and complete the National In-

ventory of Dams.

c. Scope of Inspection Program: The scope of this Phase

L I inspection report includes:

1. Gathering, reviewing and presenting all availabledata as can be obtained from the owners, previous

L owners, the state and other associated parties.

2. A field inspection of the facility detailing theF visual condition of the dam, embankments and

appurtenant structures.

3. Computations concerniig the hydraulics and hy-drology of the facility and its relationship toth, calculated flood through the existing spillway.

4. An assessment of the condition of the facilityand corrective measures required.

LIt should be noted that this report does not pass judgment

on the safety or stability of the dam other than on avisual basis. The inspection is to identify those fea-tures of the dam which need corrective action and/or fur-thur study.

1.2 Description of the Project:

a. Location: The project is located on Trading Cover Brook, a tributary to the Thames River which is

approximately 5,000 feet downstream of the dam. Route32 passes over the crest of the dam, and the townline for Norwich and Montville passes through thecenter of both Trading Cove Pond and the dam (perpen-dicular to Route 32). Both towns are located in NewLondon County. The facility is shown on the UncasvilleUSGS quadrangle map, having coordinates 410 29' 41"

L (north latitude) and 720 06' 01" (west longitude).

b. Description of Dam and Appurtenances: The dam at

Trading Cove Pond is an earth embankment dam, approxi-

mately 230 feet long and 29 feet high, with an average

crest width of 54 feet. From observations of the site,it is suspected that there is an existing masonry dam

within the outer earth embankment structure. StateRoute 32 runs along the crest of the dam, which is

paved along its entire width. Along the upstream side

of the dam there are portions of masonry wall, some ofwhich have been gunited along the left side of thespillway. The remaining part of the upstream side of

the dam is earth fill with a very irregular surface,ranging from 1.5H:lV to 2H:lV in slope. The downstreamslope of the dam is an earth embankment with a slope

of 2H:lV. It has the spillway discharge channel exit-

ing at its center.

The spillway is located at the center of the dam along

the upstream side and is an ashlar masonry structure

with a flashboard permanently attached. The discharge

channel from the spillway crosses beneath the dam in

the form of a box culvert 16 feet wide and 15.5 feet

high. The culvert is constructed of reinforced concrete

L and stone masonry. The masonry portion

is located in

L2

the approximate center of the culvert and may coincidewith what was thought to be the original masonry dam.The spillway is 29 feet long and about 10 feet high.The flashboard is 6 inches in height. The spillwaychannel on the downstream side of the dam is the naturalstreambed. Tail water in the spillway channel is con-trolled by the level of Trading Cove, which is adjacentto the Thames River. The Thames River and Trading CoveLare subject to tidal fluctuations.

An intake structure is located near the left abutmentof the dam. From the entrance, the channel appearedto be a concrete box culvert. Because it was partiallyblocked no inspection could be made of its interior fromthe upstream or downstream sides. The downstream exit[of the untake structure channel is blocked by large rip-rap piled up against its face. At the exit of this

r channel, there is a tail race which runs towards thelocation of the former mill building. The race is nowpermanently blocked off at its furthest downstream point.Along the left downstream toe of the dam, there is a

I edischarge pipe from the tail race channel to the mainstream.

c. Size Classification: SMALL - With the pool level at thetop of the dam, the impoundment capacity is 500 acre feet.The dam's heiqht above the streambed is 29 feet. Inaccordance with the guidelines of the Corps of Engineers,which state that a dam less than 39 feet in height andwith a storage of 50 to 999 acre feet is small, the damis classified as being SMALL.

d. Hazard Classification: LOW - The dam is classified as

having a LOW hazard potential because no loss of lifeand minimal economic loss are expected. A tire salesoutlet is located downstream of the dam, but dischargefrom the failure of the spillway is not expected toreach the sill elevation of the building even when failedin conjunction with high tide in the Thames River estu-Lary. Because of its width, the dam was not considered

5 as a likely possibility for failure. Only the spillwayportion was therefore subjected to a failure analysis,

L with water level at the spillway crest elevation.

e. Ownership: Ownership and responsibility for the upkeepI of the dam were difficult to determine. From availablerecords it appear that the State of Connecticut ownsbetween the highway lines of Route 32, which runs alongthe crest of the dam, while Daniel Griffin owns portionsof the dam beyond those lines. The deed for the Griffinproperty indicates that water rights and control of the

•1. [3

outlet structures are under the ownership of DanielGriffin of Griffin Tire Service, Inc., 812 West ThamesStreet, Norwich, Connecticut, 06360, telephone no.(203 889-2315).

f. Operator: The roadway along the crest of the dam andthe appurtenant drainage is maintained by the Depart-ment of Transportation, State of Connecticut. The damembankments and appurtenant facilities not on State prop-erty are presently not operated and there are no opera-tional procedures in effect.

g. Purpose of Dam: The dam was originally constructed formechanical power generation. The mill located downstreamfrom the facility was demolished in 1976. At the present

ptime there is no use for the water in Trading Cove Pond,and the dam serves no purpose other than to provide ar means of crossing Trading Cove Brook with State Route 32.

h. Design and Construction History: Nothing is known aboutthe original construction of the dam. The State ofConnecticut Department of Transportation, however, laterimproved this dam and built State Route 32 along thecrest. Inspection of the spillway channel crossing thedam indicates that the center one-third portion of thedam was probably the original structure. Both on theupstream and downstream slopes, indications are thatthe dam was extended for the purpose of widening Route 32.The original mill was demolished in 1976 when the GriffinTire Service, Inc. purchased the site.

" i. Normal Operating Procedures: There is no operational

procedure at this facility.

1.3 Pertinent Data:

a. Drainage Area: Trading Cove Pond and its drainage areaare located in New London County in the southeastern por-tion of the State of Connecticut. The basin is somewhatrectangular in shape with a longitudinal east-west axisof approximately 6 miles and a width of 3 miles. The

[" total drainage area is 13.3 square miles in size. TheLtopography is characterized by hilly terrain, with ele-

vations ranging from a high of 519 feet in the north-westerly portion of the watershed to a low of 14 feetat the elevation of the spillway at Trading Cove PondDam. Basin slopes are generally moderate. The charac-ter of the area is generally rural with some denselypopulated areas near the urban area of Norwich in thenortheasterly portion of the watershed. No signigicant

I.l_4

wetlands or other storage areas exist in the watershedto retard the peak of the surface runoff. A map of thewatershed area is attached in Appendix D of this report.

b. Discharge at Dam Site: No records of spillway or outletworks discharges are available for this site. Listedbelow are calculated discharge data for the spillway.Theoutlet works, because it is blocked, was not consideredin the calculations:

1. Outlet works: Inoperative(Dimensions unknown)

2. Maximum known flood at dam site: Discharge unknown.

3. Ungated spillway capacity attop of dam: 2,300 cfs at Elev.32.1

4. Ungated spillway capacity attest flood elevation: 2,500 cfs at Elev.34.4

5. Gated spillway capacity atnormal pool elevation: N/A

* 6. Gated spillway capacity attest flood elevation: N/A

7. Total spillway capacity attest flood elevation: 2,500 cfs at Elev.34.4

8. Total project discharge attop of dam: 2,300 cfs at Elev.32.1

9. Total project discharge attest flood elevation: 4,500 cfs at Elev.34.4

c. Elevation (Feet above National Geodetic Vertical Datum):

1. Streambed at toe of dam: 3.1

2. Bottom of cutoff: Unknown

L 3. Maximum tail water: Unknown

4. Normal pool: 13.8

5. Full flood control pool: N/A

6. Spillway crest: 13.8

7. Design surcharge(original design): Unknown

5

8. Top of dam: 32.1

9. Test flood surcharge: 34.4

d. Reservoir (length in feet):

1. Normal pool: 900

2. Flood control pool: N/A

3. Spillway crest pool: 900

4. Top of dam: 6,400

5. Test flood pool: 7,000

e. Storage (acre feet):

1. Normal pool: 20

2. Flood control pool: N/A

3. Spillway crest pool: 20

4. Top of dam: 500

5. Test flood pool: 600

- f. Reservoir Surface (acres):

1. Normal pool: 4

L 2. Flood control pool: N/A

3. Spillway crest: 4

L 4. Test flood pool: 62

L 5. Top of dam: 52

g. Dam:

1. Type: Earth embankment withsome upstream verticalmasonry walls

2. Length: 230 feet

3. Height: 29 feet

4. Top width: 54 feet

1 6

i4

5. Side slopes: Downstream 3H:lVUpstream - Irregular, 1 -2H:lVwith vertical masonry walls

6. Zoning: Unknown

1 7. Impervious core: Unknown

8. Cutoff: Unknown

9. Grout curtain: Unknown

h. Diversion and Regulating Tunnel: N/A

i. Spillway:

1. Type: Masonry with flashboard

Ogee type weir

2. Length of weir: 22 feet

3. Crest elevation (withpermanent flashboard): 13.8 feet

L 4. Gates: None

5. U/S channel: Natural bed S

6. D/S channel: Natural bed

j. Regulating Outlets: Culvert through dam;exact characteristicsand dimensions could Snot be determined.

L7

L

L7LS

SECTION 2

ENGINEERING DATA

2.1 Design: There is very little known about the design ofrthe dam. It was constructed for mechanical power genera-

tion for a downstream mill, probably during the middleof the nineteenth century. The mill structure was de-molished in 1978. Plans for the original constructionwere not available. During the reconstruction of Route 32the dam was improved and an addition was made on both theupstream and downstream sides. The original part of thedam can be seen in the existing culvert, where it coversapproximately the center third. (Refer to Photo 6).

2.2 Construction: Nothing is known about the construction ofthe original dam. Indications are that it was constructedduring the middle of the nineteenth century, but no moredefinite information is available. Later additions were

• made for the improvement of Route 32 which runs along thecrest of the old dam. Recently, further improvements were

made to alleviate drainage problems.

2.3 Operation: The dam was originally constructed for mechan-ical power generation. Presently, it serves to pass StateRoute 32 over Trading Cove Brook. Since the demolitionof the mill building, the tail race of the dam was recon-nected to the original stream channel. There are no opera-tional procedures in effect at the site and no records ofpast operations were found to be available.

2.4 Evaluation:

a. Availability: The facility is available for visualinspection since it serves as a roadbed for a statehighway. All accessible operating parts of the facil-ity were inspected. No plans or other design informa-tion were found to be available.

b. Adequacy: The limited amount of data available wasinadequate to perform an in-depth assessment of thedam and appurtenant facilities. Therefore, the final

*assessment of this dam must be based primarily onvisual inspection and hydraulic and hydrologic com-putations of spillway and outlet capacity

c. Validity: Due to the lack of available data, theconclusions found in this report are based on visualinspection and hydraulic and hydrologic corputations.

8

SECTION 3

VISUAL INSPECTION

3.1 Findings:

a. General: An inspection of Trading Cove Dam was per-formed on April 8, 1981 by Lenard & Dilaj Engineering,Inc. with the assistance of Geotechnical Engineers,Inc. The weather was sunny and the temperature wasabout 650. At the time of inspection, the water levelin the pond was about 6 inches above the top of theflashboards of the spillway.

As a result of the visual inspection, the Trading CoveDam and its appurtenances were found to be in faircondition.

b. Dam: The dam is an earth embankment dam with a54 foot wide crest. Route 32 runs along the crestof the dam. The upstream section consists of an ash-lar masonry wall, partially gunited, with the lowerpart being an earth slope. The downstream section isa 2H:IV earth slope.

1. Crest: The entire crest of the dam is pavedand constitutes Route 32. The downstream sideof the crest is lower because there is a curve inthe road with a super-elevation on the upstreamend. No cracks of significance were observed onthe pavement.

L 2. Upstream Slope: The upstream slope of the damconsists of an ashlar masonry wall near the crestand an earth embankment on the lower part of theslope (see Photo 1). Part of the wall on the leftside of the spillway has been gunited. Some ofthe gunited areas near the spillway have begun toshow signs of spalling, as seen in Photo 1. Tothe right of the spillway there are areas whichhave mortar missing from between the stone blocks.Earth fill has been placed against the lower partof this wall, but the fill has a very irregularsurface and an extensive growth of small trees.The retaining wall just to the left of the spill-way has also been gunited and has had PVC drainpipes installed about 2 to 3 feet into it.

3. Downstream Slope: The downstream side of the damhas a slope of about 2H:lV. It is basically a

9

I.I

grass slope with some brush and small trees(up to a trunk diameter of 3 inches) growing onit (Photo 3). There are some footpaths alongthe slope which have resulted in erosion, partic-ularly near the wing walls of the outlet channelto the spillway, as seen in Photos 3 and 4. Theerosion here is as deep as 2 feet along the rightside of the structure. No seepage or sloughingof the embankment was observed along any of thedownstream areas. The lower part of the slope isprotected against tail water erosion by riprapwhich extends about 10 feet up the slope in thevicinity of the wing walls of the outlet structure.

c. A purtenant Structures: The appurtenant structuresor this dam are the spillway located near thecenter of the dam and an outlet structure with atail race channel near the left abutment.

1. Spillway: The spillway consists of an ashlarmasonry structure with flashboards (Photo 2)and training walls on both sides (Photo 1).The spillway discharge channel passes throughthe dam. The upstream and downstream sectionsof the channel are a concrete box structure,while the central section has ashlar masonrywalls and a concrete slab roof (Photo 6). There

are drain holes in the downstream section ofthe channel and both the concrete and ashlarmasonry appear in good condition. There was noflow observed coming out of the drain holesalong the masonry or concrete walls. Minor efflor-escence and evidence of seepage were observed onthe masonry walls.

L2. Outlet Structure and Tail Race Channel: The

intake is located near the left abutment. Theconcrete is in good condition (Photo 5), butthere is no gate, and the trash rack has beenremoved and lies at the bottom of the entrancechannel. The conduit through the dam is, at

Lits upstream end,a concrete box (Photo 5).The conduit then turns to the left at a rightangle. The nature of the channel from thispoint could not be observed or otherwise deter-mined. At the downstream side of the dam, the

conduit could not be observed, because it wascovered with stones. The water flows up throughthe stones (photo 7), and then continues intoa tail race channel. The tail race channel has

pa natural earth embankment on its left side andL a concrete wall on its right. The right side of

1.110

I0

this wall has an earth embankment placed againstit as shown on Photos 7 and 8. About 20 feetdownstream of the conduit outlet, there is a pipewith the gate removed that conveys the flow tothe downstream spillway channel (Photos 7 and 8).The concrete wall of the tail race channel iscracked and shows displacements across the cracksof up to about one inch (Photo 8). The earth

Lembankment behind the wall is overgrown withbrush and has an irregular surface (Photo 8).

d. Reservoir Area: There is considerable siltation inthe reservoir reaching the spillway crest. There isa building and a parking area at the reservoir edgeimmediately upstream of the right section of the dam.If the water level were to reach the crest of the dam,the parking lot and building would be flooded with afew feet of water.

e. Downstream Channel: The downstream channel is thenatural streambed. There is a tail water controlled

Fby the level of the Thames River, but there are nosignificant obstructions to the flow.

3.2 Evaluation: On the basis of the visual inspection, thedam and its appurtenant structures are judged to be infair condition. This assessment is based on the erosionon the downstream slope, on the tree and brush growth onboth embankment slopes, on the missing grout and spallingof the upstream walls, and on the inoperative condition

L and blockage of the outlet structure near the left abut-ment.

The present configuration of the dam appears to be theresult of substantial widening and raising of an earlierdam.

L "2

[Q

11i

SECTION 4

OPERATIONAL AND MAINTENANCE PROCEDURES

4.1 Operational Procedures:

a. General: The State of Connecticut owns the land andappurtenant structures of the dam between the highwaylines of Route 32 which runs along the crest of thedam. Daniel Griffin owns the remaining portions ofthe dam and appurtenances beyond the highway lines.According to the deed, Griffin also has water rightsin the pond and has control of the outlet structureson the dam controlling flow toward the original milllocation. The State of Connecticut Department ofTransportation has made improvements to the road anddrainage facilities. However, there are no operationalprocedures in effect for the spillway or the outletworks by either the State or Daniel Griffin. Waterlevel is maintained by a permanently set 6" high flash-board bolted to the spillway crest.

b. Description of Any Warning System in Effect: Thereis no emergency or contingency plan in effect at thisfacility.

4.2 Maintenance Procedures:

a. General: Maintenance of the spillway is provided bythe Department of Transportation of the State of Con-necticut. Further upst:-eam or further downstream fromwhere the state highway passes there is no maintenanceprovided.

b. Operating Facilities: The outlet works trash rack hasbeen removed from its groove and is blocking the flow.There is no maintenance provided here.

4.3 Evaluation: Maintenance of the dam and appurtenant facili-ties appears to be limited to that required for the properdrainage along the state highway. Embankments should bemaintained free of brush and trees so that inspections canbt. performed.

12

SECTION 5

EVALUATION OF HYDRAULIC/HYDROLOGIC FEATURES

5.1 General: Trading Cove Dam is an earth embankment dam with somevertical masonry walls along the upstream side. It is about230 feet long, 54 feet wide at the crest, and 29 feet highabove the streambed. The spillway is located near thecenter of the dam, and about 3 feet away from the verticalwall which forms the entrance to the culvert which passesthrough the dam. The spillway most closely resembles anogee type of weir, as shown by the sketches in the attachedcalculations of Appendix D. As water level continues torise above the level of the spillway, the discharge wascalculated as orifice flow, due to the presence of theculvert in close proximity to the crest. The additionaldischarge capacity which could be obtained from the outletworks near the left abutment was not considered becausethe outlet side of the structure appeared to be permanentlyblocked by stones placed in front of the opening. Anyflow passing through the stones during a storm was con-sidered to be insignificant. Also the nature of the pass-age through the dam could not be determined and its hy-draulics not calculated.

The downstream channel of the dam first forms a smallponded area and then flows in a shallow stream down toTrading Cove, a tidal backwater of the Thames River. Thedistance from the dam to Trading Cove is approximately800 feet.

The watershed covers an area of 13.3 square miles, all ofwhich contributes directly to Trading Cove Pond. No other

L significant dams or impoundments are located within thewatershed, and no substantial wetland areas exist whichmight add to the storage of storm water flows to decreasethe peak outflows.

At spillway elevation, Trading Cove Pond has a storagecapacity of approximately 20 acre feet. This increasesto 500 acre feet at the top of the dam and to 600 acrefeet at the test flood level.

5.2 Design Data: No design data was found to be availablefor Trading Cove Dam.

5.3 Experience Data: No records on past experience werefound to be available for this site.

13

[0

5.4 Test Flood Analysis: Based on the "Recommended Guidelinesfor Safety Inspection of Dams" the Trading Cove Dam isclassified as SMALL in size and as having a LOW hazardpotential. The test flood for these conditions rangesfrom the 50-year flood to the 100-year flood. Based onthe size of the dam and the storage capacity, the 100-yearflood was chosen as the test flood.

Using the HEC-l Flood Hydrograph Computer Program developedby the Army Corps of Engineers for dam safety investiga-tions, the inflow and outflow for the test flood were foundto be 4,800 cfs (360 csm) and 4,500 cfs, respectively. Asa basis of comparison, the PMF resulted in an inflow of19,200 cfs and an outflow of 18,900 cfs. The outflow capac-ity of Trading Cove Dam at the level of the top of the damis 2,300 cfs, which represents 51% of the test flood outflow.The maximum overtopping associated with this outflow is2 feet. The assumed pool elevation at the beginning ofthe test flood routing is 13.8 feet, the spillway elevation.

5.5 Dam Failure Analysis: A dam failure analysis was performedusing the "Rule of Thumb" method for estimating downstreamdam failure hydrographs, as developed by the Corps of Engi-neers. Failure was assumed to occur when the water levelin the pond was at the level of the crest of the spillway.Because of the crest width, the dam was not considered asa likely possibility for failure. Only the spillway por-tion was therefore subjected to a failure analysis.

Because the outlet works is partially blocked, an insigni-ficant discharge was assumed prior to the failure of thedam. On the downstream side, however, the failure dischargewas calculated in conjunction with high tide elevation inthe Trading Cove portion of the Thames River tidal estuary.

IThe calculated dam failure discharge, based on an assumedbreach width of 22 feet (the width of the spillway), is1,350 cfs. This will produce a depth of flow of approxi-

r mately 4 feet in the vicinity of the tire outlet downstreamL. of the dam. This level is not expected to reach the sill

elevation of the building even when failure occurs in con-junction with high tide. Beyond the tire outlet there areno structures before the flow reaches Trading Cove. Theanalysis therefore covered a distance of 600 feet as shownby the calculations in Appendix D.

L The breach of the spillway at Trading Cove Pond Dam is notexpected to cause any loss of life and only minimal damageand economic loss to the tire outlet on the downstream side.

rBecause flood depths are not expected to reach the sill ele-vation of the building, the dam is classified as having aLOW hazard potential.

ILL

S14 @

___________-

0

SECTION 6

EVALUATION OF STRUCTURAL STABILITY

6.1 Visual Observations: The visual inspection did notdisclose any evidence of structural instability.

6.2 Design and Construction Data: There was no designand construction data available to permit a formalevaluation of the stability of the dam.

6.3 Post Construction Changes: The construction ofRoute 32 apparently widened and raised an existingdam. In its present configuration, the crest isabout 54 feet wide and the dam is a maximum of about29 feet high.

6.4 Seismic Stability: The dam is located in SeismicZone 1 and, in accordance with the Phase I inspectionguidelines, does not warrant seismic stability analysis.

1.LS

.

[

S ~15

SECTION 7I

ASSESSMENT, RECOMMENDATIONS, AND REMEDIAL MEASURES

7.1 Dam Assessment:

L a. Condition: The visual inspection indicated that the

dam and its appurtenant structures are in fair condi-tion. There are some items requiring maintenance toprevent deterioration of the dam:

1. Erosion of the downstream slope adjacent to thewing walls of the outlet structure for the spill-way discharge channel.

2. Tree and brush growth on the upstream and down-stream slopes.

3. Regrouting of the upstream wall.

4. The outlet structure, whose trash rack is not inplace and whose discharge channel is blocked.

b. Adequacy of Information: There was no design or con-struction data available, and thus the assessment ofthe condition of the dam is based on the visual in-spection and engineering judgment.

16

16

0I

7.3 Remedial Measures:

a. Operating and Maintenance Procedures:

1. Repair the erosion adjacent to the wingwalls ofthe culvert on the downstream slope of the damwith crushed stone.

2. Remove small trees and brush growing on the slopesand within 20 feet of the toe, and develop protec-tion against erosion with grass or riprap.

3. Regrout the upstream ashlar masonry wall and re-pair the gunited section.

4. Reinstall the trash rack removed from the outletworks and clean the general area around it.

5. Establish a program of annual technical inspections* by a registered professional engineer.

6. Implement and intensify a program of diligent andperiodic maintenance including, but not limited to,mowing brush on slopes, backfilling animal burrowswith suitable well tamped material, and cleaningdebris from spillway and slopes.

A7.4 Alternatives: There are no practical alternatives to the

above recommendations.

[ 17

I

I

I[

I

rAPPENDIX A

INSPECTION CHECKLIST

I

I

LL

LL

I

VI S [AL I NSPECT ION CIt CK1. IIt1FAR1 Y ORGANJIM7~IION

RO . TRAING COVE DAM DAl I April 8, 1981

TIME 12:30-2:30 pm

WEATHER Sunny, 650

W.s. ELEV. 6 inches U.S. DN.S.

-~[PARTY: .above !Zashboards

1. John Lenard - L.D.E.I. 6. Karl Acimovic - L.D.E.I.

2. Michael Dilaj - L.D.E.I. 7

3. Michael Romanowski - L.D.E.I. 8.Mark Vasington - L.D.E.I. 9

Gonzalo Castro - L.D.E.I1. 30._________________

PROJECT FEATURE IrJSPECT[()0 BY REMARKS

1Geotechnical Gonzalo Castro

2. Structural, Civil John Lenard

3. Hydraulics, Hydrology Karl Acimovic, MichaeZ Dila,]

L. Survey, Civil Michael Romancm'ski

Surveu Mark Vasinqton

6.

7.

A.

in.

* I A-1

II

I I'F*RIODIC INSP[(TI)ON CHLCKI 1IJ

PROJECT TRADING COVE DAM DATE April 8, 195

PROJECT IrATUR[ __ANL

OISCIPI.NE A II[H[

AREA EVALUATED COND I T I ON

DAM EmrBANKHENT

L Crest Elevation 32.1

Current Pool Elevation 13.8, 6 inches above flashboards

[ Maximum Impoundment to Date Unknown.

Surface Cracks None observed.

F Pavement Condition Good. 0

Movement or Settlement of Crest None observed.

Lateral Movement None observed.

Downstream side of crest is lower thanVertical Al ignmnt upstream side because of superelevation IH z l imof road.

Hori zontal Ali qnment -Too irregular to judge.

Condition at Abutment and at Concrete Erosion guZZlies on downstream slope

Structures along spillway walls.

Indications of Movement of Structural Not applicable.

[ Items on Slopes

Trpspassinq on Slopes Footpaths, some erosion.

[ Slouqhin or Erosion of Slopes or None observed.Abutments

Rock Slope Protection - Riprap Failures No protection of upstream slope. Riprap.at spillway outlet and at toe of

Urnu',udl Mover,.nt or Crackinq at or Near downstream slope.T Moe None observed.

Jnusual rFti~rnkment or Downstream None observed.

Pipinq or Boils None observed.

Foundation Drainaqe Features None known or observed.

Toe Drains None known or observed.

Instrumentation System None known or observed.Nuerous trees and brush on urs ream

Veetation A-2 slope. A few trees up to 3 inces on.' wnsvrea s~ope.

PERIODIC ITJSPLCTION CtI[CKI ISl

PROJECT TRADIY.'- COVE DAM ! FlATj AvriZ 8, 1981

PROJECT FCATIIRF NAMI

DISCIPLINE NAIL:L

AREA EVALUATED CONDITION

DIKE EMBANKMENT Tailrace channel (to dam). Side wall isan earth dike with an upstream concreteCrest Elevation wall.

Current Pool Elevation PracticallZ nc water in channel.

F Maximum Impoundment to Date

L Surface Cracks Cracks on upstream concrete wall.

Pavement Condition Not applicable.

Movement or Settlement of Crest None observed.

Lateral Movement Noted \1 inch across cracks in concrete.

Vertical Aliqnnent Good.

Horizontal Aliqrnient Cracked. As built alignment is curved.

Condition at Abutment and at Concrete Not applicable.Structures

Indications of Movement of Structural Not applicable.Itels oi Slopes

L.

Trespassing on Slopes Footpaths.

Slounhinq or Erosion of Slopes or None observed.

Abutmrnts

Rock Slope Protection - Riprap Failures Riprap recently installed at pipe outlet(downstream side of dike).

Unusual Movement or Cracking at or None observed.

j Near Toes

Unusual Entankment or Downstream None observed.See piiqe

Piping or Boils None observed.

Foundation Drainaqe Features None known.

Toe Drains None known.

[ Instrumentation System None known.

Vegetation A-3 Grass, few small trees.

: D I

IM 001 C I NSPrC1 ION CII.(, KI I I

PROCT_ TRADING COVE DAM lAII April 8, 1981

PROJECT I-FATUR_ NAMF

DISCIPLIN[ NACO

I ARLA L VALUAT ED COND IT ION

OUTI ET WORKS - INTAKE CHANNEL ANDIN-T AKEC STrUC TURE

a. Approach Channel No approach channel.

FSlope ConditionsBottom Conditions

Rock Slides or Falls

Log Boom

L. Debris

Conditiun of Concrete Lining

Drains or Weep Holes

b. Intake Structure Reinforced concrete, ,5 ft. by 5 ft.

Condition of Concrete Good. P

Stop Logs and Slots Trash rack out of place, in strewn. Gatemechanism and gate missing.

L

I-l

'A-4 p

4'i

PRIO)!IC I NSP[C1IION CIIICL I ,l

lIOJI CT TRADING COVE DAM Al\L April 8, 1981

PRRJECT FFATUR , __AriF .

DISCIPLINE !_NAlE

AREA EVALUATED CON IL ION

L OUTLET WORKS - CONTROL TOWER There is no control tower.

a. Concrete and Structural

General Condition

[ Condition of Joints

Spallinq

Visible Reinforcinq

Rustinq or Staining of Concrete

Any Seepage or Efflorescence

Joint Alignment

Unusual Seepage or Leaks in GateChatiter

Cracks

Rustiiq or Corrosion of Steel

b. mechanical and Electrical

Air Vents

Float Wells

L- Crane Hoist

L Elevator

Hydraulic System

Service Gates

Emerqency Gates

Liqhtninq Protection System

Emergency Power Svstem

Wirinq and Lin' ,.qSystem A-5

Lm

I PEIRIODIC INSPF-CTION' CHECKI I jI

PROJ[CT TRDING COVE DAI, DATE ApriZ 8, 1981

PROJECT [LAI~l)f ________________ NAME _________________

~ DISCIPLINE NAME__________________________________

AREA EVALUATEDCODTN

OUTLET WORKS - TRANSITION AND CONDUIT Not observabZe.

General Condition of Concrete

r Rust or Staininq on ConcreteSpa Ilinq

Erosion or Cavitation

Cracking

Alignment of Monoliths

Alionmenit of Joints

Numberinq of Monoliths

A-

P'ERIODJIC INSPE'CTIJON -CiIICKI PJ~PkWOJ LCT TRADING COVE DAM [JAlE April 8, 1981

PkO)JECT H. ATIJIW ______________________ NA!1F________________

DISCIPLINE _____________________ NAML______________

AREA EVALUATED CONDITION

r OUTLET WORKS - OUTLET STRUCTURE AND Outlet cnanne. is tai~race (to damn).OUTLT CHNNELSee comments under dike embankment.

Geneal ondtionof onceteOutlet is covered with stones. Pipe is~ [ eneal ondtionof oncetenot observable. Water surfacing through

Rust or Stainingstn.

Spalling

Erosion or Cavitation

Visible Reinforcinq

Any Seepage or Efflorescence

Condition at Joints

Drain holes

Channel

Loose Rock or Trees OverhangingChannel

Condition of Discharge Channel

A-7

PERIODIC INSPECIO1011 ClIHfI ]S1

i [ LCT TRADING COVE POND DATF April 8, 1981

iNKOJFC] FEA1 UR[ NAMI

DISCIPLINE NAMI.

AREA EVALUATED COTJDIT ION

OUTLET WORKS - SPILLWAY WEIR, APPROACHAND DISCHARGE CHANNELS

a. Approach Channel No approach channel.

General Condition

Loose Rock Overhanqing Channel

Trees Overhanging Channel

Floor of Approach Channel

b. Weir and Training Walls Small training wall at right side only.

General Condition of Concrete Ashlar masonry with gunite cover on leftside and pointed joints on right side.

Rust or Staining Gunite in good condition; ,30% to 40%of mortar is missing.

Spalling None observ;ed.None observed.

Any Visible Reinforcing None observed.

Any Seepaie or Efflorescence None observed.

Drain Holes PVC pipes on left side, n,2 to 3 feet deep.

c. Discharqe Channel Under dam, the natural stream channel.

General Condition Good.

Loose Rock Overhanqing Channel None.

Trees Overhanqinq Channel None.

Flonr of Chdnnel Gravel.

Other Obstructions None.

L Other Convients

A-8

PERIODIC INSP[ClION C1IECKLIST

PkOJECT TRADING COVE DA DATE April 8, 1981

PROJECT IIATIRF NAME

DISCIPLINE NAME_

AREA EVALUATED CON) I T ION

OUTLET WORKS - SERVICE BRIDGE There is no service brido7e.

a. Super Structure

Bearinqs

Anchor Bolts

Bridge Seat

Longitudinal Members

Underside of Deck

Secondary Bracing

deck

Drainaqe System

RailIi ngs

Expansion Joints

Pa i nt

b. Abutment & Piers

General Condition of Concrete

Aliqnment of Abutment

Approach to Bridge

Condition of Seat & Backwall

A-9

I

II

[Ii'

[APPENDIX B

k

L ENGINEERING DATA

i1%

S

L

II SI[

S

L

I

U

r- APPENDIX C

PHOTOGRAPHS

L

OL

L:|S

Photo 1. Upstream view of the dam from parking lot

Lat edge of pond. Note cement bag retaining

wall at left end of culvert embankment.

Photo 2. Spillway weir and flashboard at inlet of

I! culvert.

US ARM ENINE DI V. NEW ENGLAND NATONLDRORANO COVE DAM

WALMAM. U*SIACNUI(TTI INSPECTION OF CT 00237

LENA~~ I. AJ ENGINEERING, INC. "MAY 19814118Commg9CTICUT NON-FED. DAMSC-

4 Ib~c-2-

rZ

-il

rPhoto 3. View of downstream slope of damn and spill-way weir on upstream side (as viewed through

L the culvert). Note erosion along both wingwalls of culvert outlet.

i7,

Pht 4.Coepo rsoSaogtergtwnwal oftecletotlt

US AMY EGINER DV. EW EGLAD TRDIN COV DA

Lop f loola AINLPORMO OWCONCIU

L USEARYDA ENGINEE IV. NC. -LN NATONA 1981N CVE

8TORMeBCokMNICT NON-FED. DAMS*mo~w~.C-3

~.4

rphoto 5. Intake structure near left abutment of dam.Note trash rack tilted towards the pond.

07

Photo 6. Spillway channel (culvert) through damn asEl seen from downstream end. Note stone masonrycenter portion of spillway channel, which

probably indicates the size of the original dam.

L US ARMY ENGINEER DIV. NEW ENGLAND TRADING_____COVE____DAM _

COIIHSSH101A111 NATIONAL PROGRAM OF NORWICH, CONNECTICUT

WATA.MSAMSTSINSPECTION OF CT 00237LLENARO DILAJ ENGINEERING, INC. MAY 1981

GTOSSS.COHICTICUTr NON-FED. DAMSC-ENGINEER C-

Photo 7.I A Tailrace channel for conduitpassing through dam. outletis buried beneath tl e stones inthe foreground. Note gate slotfor discharge pipe from channelinto main stream at right ofphoto on retaining wall.

Photo 8.

Downstream side of dischargepipe from tailrace channel.

Note spalling of concrete wall.

F4

0US ARMY ENGINEER DIV. NEW ENGLAND TRADING COVE DAMCORPS OF, 101109011 NATIONAL PROGRAM OF NORWICH ICONNECTICUT

WALTHAM, 411811ACH911(TS

INSPECTION OF CT 00237LUNARD-DILAJ ENGINEERING, INC. MAY 198r1

0 TORN S.COPNE C TIC UT NON-F1-.% DAMSC-5

- 4.

4" k

P'hoto 9. Downstream view of Griffin Tire Co.from toe of dam.

US ARMY ENGINEER DIV. NEW ENGLAND TRADING COVF DAMCOMPS op ENGINEERS NATIONAL PROGRAM OF NORWICH, CONNECTICUT

WATA.MSAHSTSINSPECTION OF CT 00237LENARO-DILAJ ENGINEERING, INC. MY18

STOMRBCONNECTgCU? NON-FED. DAMSC-

I

APPENbIX b

HYDROLOGIC AND HYDRAULIC

[ COMPUTATIONS

I[

.L

[

NARD & nlt..AJ ENGINEERING, INC. (JOB -cov-365 Storrs Road SHEET NO. OF

S!ORRS. CONNECTICUT 06268 CALCULATED .YiA± DATEk203) 429-7308

CHECKED SY DATE

SCALE

DETERMINATION OF SPILLWAY TEST FLOOD*

A. SIZE CLASSIFICATIONTHIS DAM:

Based on either storage or height

Storage 50-999 Ac.-Ft. _______ ._-__

Height 25-39 Ft. r7,

IntermediateStorage 1,000-50,000 Ac.Ft.Height 40-100 Ft.

Storage More than 50,000 Ac.-Ft.Large Height Greater than 100 Ft.

B. HAZARD POTENTIAL CLASSIFICATION

Category Loss of Life Economic Loss

QNone expecteSignificant Few Appreciable

d4High More than few Excessive

Hazard Classification LON//

C. HYDROLOGIC EVALUATION GUIDELINES

Hazard Size Spillway Test Flood

c 7 I50 to 100-Year FrequencIntermediate 100-Year Frequency to PMFLarge PMF to PMF

Significant Small 100-Year Frequency to PMFIntermediate PMF to PMFLarge PMF

High Small PMF, to PMFIntermediate PMFLarge PMF

Spillway Test Flood ?(2- FA

• Based upon "Recommended Guidelines for Safety Inspection ofDams" Department of the Army, Office of the Chief of Engineers,November 1976.

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LENARD & DILAJ ENGINEERING, INC. JO1066 Storrs Road SHEET NO. I F

STORRS, CONNECTICUT 06268 CALCULATED BY ILL -DATE ~(203) 429-7308CHKEBYDT

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LENARD & DILAJ ENGINEERING, INC. J- oO e4

1066 Storrs Road SHEET NO

STORRS, CONNECTICUT 06268 CALCULATED BY. DATE 45

1-10(203) 429-7308 fl2- //---CHECKED BY DATE

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LENAD &DILAJ ENGINEERING, INC.LEAR & 1066 Storrs Road SHEET NO ___________OF

STORRS, CONNECTICUT 06268 CALCULATED BY4Ief DATE(203) 429-7308 CEKDYDT

CHCKDB-DATE ~~ ~SCALE _______________________________

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LENARD & DILAJ ENGINEERING, INC.1066 Storrs Road SHEET NO 0 _ _________

STORRS, CONNECTICUT 06268 CALCULATED BY Jr-AA . DATE________(203) 429-7308 CHECKED BY___________DT

_______

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LENARD & DILAJ ENGINEERING, INC. JOB___________ OF

1066 Storrs Road SHEET NO I

STORRS, CONNECTICUT 06268 CACLTDB6K"1DT(203) 429-7308 CLUAE Y /"DT

CHECKED BY DATE

SCALE _________________________

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LEAD&DILAJ ENGINEERING, INC. '6 2 LLEAR &1066 Storrs Road SHEET NO. 6 OF

STORRS, CONNECTICUT 06268 CALCULATED BY DATE

(203 4297308CHECKED BY /' DATE________

SCALE

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LENARD & DILAJ ENGINEERING, INC. SHETN 7 OF~V 461'1066 Storrs RoadSEENO7O__________

ISTORRS, CONNECTICUT 06268 CALCULATED BY At- 4 DATEI ~(203) 429-7308 CHECKED BY___________ DATE

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