DAM SAFETY INSPECTION REPORT GLENWOOD LAKE DAM CLASS B, INTERMEDIATE HAZARD DAM

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1 May 1, 2013 DAM SAFETY INSPECTION REPORT GLENWOOD LAKE DAM CLASS B, INTERMEDIATE HAZARD DAM Name of Dam: Glenwood Lake Dam Westchester County, NY, NYSDEC ID No NATDAM ID No. NY13618 Hazard Potential: B = Intermediate Date Inspected: 02/28/2013 Pool Elevation: Minor overflow (1-2 inches) at spillway crest (vertical datum unknown). Weather Conditions: temperature 41 F +/- and partly cloudy, light rain Tailwater Elevation: No backwater 1. NAMES/TITLES OF PARTICIPANTS: Inspecting Engineer: William Broderick, P.E., Principal, Paul C. Rizzo Engineering New York, PLLC (RIZZO) Other Participants: Barry Nechis, Captain, New Rochelle Fire Department, Emergency Management Coordinator Kaz Orszulik, Senior Engineer, Department of Public Works, City of New Rochelle 2. INTRODUCTION The year this dam was built is unknown. Glenwood Lake is bounded on the north by Glencar Avenue on the east by Bergholz Drive on the south by Lakeside Drive and on the west by Inwood Place and Seventh Avenue. It is near the New Rochelle/Pelham border. Class B Dams are located in areas where failure may damage isolated homes, main highways, and minor railroads, interrupt the use of relatively important public utilities and/or will cause substantial economic loss or substantial environmental damage. Class B dams are consider to be Intermediate Hazard dams. -Do Not Release-

2 May 1, 2013 The latest New York State Department of Environmental Conservation (NYSDEC) safety inspection was conducted on June 11, In accordance with 6NYCRR Part , the owner of a Class B dam is required to: Operate and maintain the dam and all appurtenant structures in a safe condition at all times; Maintain in good order all available records regarding the dam, and provide those records to any new owner; Develop and implement an Inspection and Maintenance (I&M) Plan; Develop and submit to NYSDEC Dam Safety Department an Emergency Action Plan (EAP) and update the EAP annually; Submit to the NYSDEC Dam Safety Department an annual certification of ownership indicating that the I&M Plan is current and is being implemented, and that the EAP is current; Conduct Safety Inspection by a Professional Engineer on a regular schedule as defined in the I&M Plan; Conduct a full engineering assessment every 10 years, the first engineering assessment is due by August 19, 2016; and, Report flows in erodible auxiliary spillway. RIZZO has prepared this Inspection Report for the City of New Rochelle, New York. The scope of this safety inspection is to identify potential problems with dam performance, to identify additional investigations and analysis that may be required, and to provide recommendations for correcting deficiencies in order to meet the NYSDEC dam safety regulations. This Report summarizes our review of available documents and our field inspection conducted on February 28, Facility data, visual inspection checklists, findings and recommendations, and relevant photographs are included herein. The dam and appurtenant works are herein referred to as left side or right side from the perspective of looking at the dam from the upstream reservoir side. Water surface and structural dimensions are referenced to an unknown datum used in earlier documents but which provide the dams relative physical dimensions. A Project Location Map and Site Plans are presented in Appendix A. The Dam Safety Checklist and Inspection Photographs are presented in Appendices B and C, respectively. Page 2 of 10 -Do Not Release -

3 May 1, 2013 An engineering assessment of spillway capacity and structural stability of the dam are beyond the scope of this Report. 3. PROJECT DESCRIPTION The year this dam was built is unknown. It presently functions as a recreational resource. The dam is located on a tributary to the Hutchinson River in the City of New Rochelle, which is in the Lower Hudson Watershed Basin. No records from subsurface investigations which may have been done at the time of construction are available. Original construction drawings and specification were not available. Some limited data from the New York State Inventory of Dams indicates that this is a stone masonry dam and earth embankment abutments. There are no operating or water level records available for this Dam. See Table 1 for a summary of facility data. TABLE 1 FACILITY DATA Geographical Location GLENWOOD LAKE DAM NYSDEC ID# NATDAM ID # Date of completion New Rochelle, Westchester County, NY NY13618 Latitude (N) Longitude (W) Purpose NYSDEC Hazard Classification Drainage Area Dam Type Maximum Dam Height Dam Length Masonry Dam unknown (no available design or construction records) Recreation Class B, Intermediate Hazard Potential 0.12 square miles (0.08 estimated by PCR) Stone Masonry and Earth Embankment 12 ft 335 ft (estimated by PCR) U/S face: vertical D/S face: vertical Crest Elevation: unknown Crest Width: 6 to 9 inches Base Width: unknown Page 3 of 10 -Do Not Release -

4 May 1, 2013 TABLE 1 FACILITY DATA (CONTINUED) Spillway Earth Embankment (downstream of masonry dam) Normal Pool Elevation Reservoir Area Normal Storage Capacity Spillway Capacity Low Level Outlet UNKNOWN VERTICAL DATUM SOURCE: NYS DAM INVENTORY GLENWOOD LAKE DAM 6 ft wide semi-circular drop structure pit w/ small diameter metal pipe discharge. Pipe outlet location is unknown. U/S slope: about 1V:2H D/S slope: steep slope not verified Crest Elevation: unknown Crest Width: varies 5 to 6 ft At low level outlet crest 4 acres w/water level at top of low level outlet 7 acre-ft w/ water level at top of low level outlet 18 cfs w/water level at top of low level outlet None Glenwood Lake Dam is an earth embankment with a stone masonry upstream vertical parapet wall. The depth to the foundation could not be verified. The dam is about 335 feet long (estimated not surveyed) with a maximum dam height of 12 feet (based on state inventory data). The spillway. is located near the center of the dam. It consists of an uncontrolled overflow stone/masonry weir a few inches below the crest of the stone/masonry wall. The pit discharges into a buried metal pipe projecting downstream through the earth embankment. The outlet from the discharge pipe was not located due to extensive vegetation and debris on the steep downstream slope. The crest of the embankment dam is actively used by area residents as a walking trail. Overhanging trees, broken limbs, and downed trees present a hazard to all who use this area as a walking trail. 4. FINDINGS & RECOMMENDATIONS We offer the following observations and recommendations to assist the Owner in maintaining safe long term performance of the Dam structure and its appurtenant works. Page 4 of 10 -Do Not Release -

5 May 1, 2013 Findings Reservoir The reservoir rim shows signs of minor shoreline erosion and instability. No shoreline slope protection was observed. It was indicated that the reservoir is spring fed, augmented with storm water runoff. The depth of the reservoir pool is unknown. There are two sprinkler pipes located at both ends of the reservoir for aeration purposes. Information on the operation and maintenance of this system was not available at the time of inspection. Earth Embankment This dam is constructed of unclassified earth fill. Crest width is about 5 to 6 feet. There is a stone/masonry parapet wall on the upstream face. Downstream slope is steep but could not be inspected because of the accumulated vegetation and miscellaneous debris from recent storms. The debris consists of felled trees, brush, slash, and miscellaneous debris that has been placed over the slope from the crest. The maximum height of the embankment is reported to be about 12 feet but this could not be verified. The depth and character of foundation conditions for the dam is unknown. Brush, saplings and large trees on the upstream and downstream slopes, and near the crest, are detrimental to long term safe performance of the dam. The existing upstream stone/masonry parapet wall has been disturbed by tree roots and is partially damaged. There is active leakage through several sections of the parapet wall. This condition is a developing potential failure mode. In its present state the masonry wall may not function as intended to protect the earth embankment slope from wave and ice damage. This woody vegetation should be removed and the stone wall repaired at the earliest practical opportunity. Page 5 of 10 -Do Not Release -

6 May 1, 2013 On the downstream slopes there are several large diameter trees, heavy brush, and vegetative cuttings. These are also detrimental to long term safe performance of the dam. All vegetation and debris should be removed from the downstream slope to provide access for inspection and maintenance of the slope. All large diameter trees (6 inch and above) should be checked and monitored by a tree specialist. At the first sign of disease or distress, they should be removed before they have a chance to fall over in a wind storm and cause major disturbance and potential breaching in the downstream slope of the embankment. For erosion protection, it is recommended that a grass cover be established and maintained for the downstream embankment slope. There are no records available that demonstrate acceptable factors of safety for structural stability for all potential loading conditions including ice loading, extreme flood events that may lead to overtopping the dam, or seismic events. Spillway The spillway structure, located near the center of the dam, contains a metal pipe which passed through the embankment dam. Loose stones, leakage, and vegetation were observed all around this structure. No information was available at the time of inspection regarding the configuration of the pipe or where it discharges on or beyond the downstream slope. Dam safety regulations require that, assuming no inflow, the service spillway, or low level outlet, should have sufficient capacity to evacuate 75 percent of the storage between the auxiliary spillway crest and the service spillway crest within seven (7) days. This is an uncontrolled overflow spillway structure, which provides no emergency maintenance drain capability. An investigation should be made to document the configuration of the spillway. A maintenance program should be developed and initiated. Low Level Outlet There is no low level outlet control for this dam. Page 6 of 10 -Do Not Release -

7 May 1, 2013 General Comments about Vegetation Impacts on Earth Dikes and Masonry Dams Contrary to common belief, tree and woody vegetation penetrations of earthen dams have been demonstrated to be causes of serious structural deterioration and distress that can result in failure of earthen dams and uncontrolled release of impounded water. The extent of the tree and vegetation problems noted during this inspection indicates that the existing trees, woody vegetation, briars, and vines interfere with effective safety inspections and hence present a significant dam safety issue. Other potential dam safety problems caused by woody vegetation growth on the earth dikes include: Potential for uprooted trees that produce large voids and reduced freeboard and/or reduced dike cross-section for maintaining stability; Decaying roots that create seepage paths and internal erosion problems; Interference with effective dam safety monitoring, inspection and maintenance for seepage, cracking, sinkholes, slumping, settlement, deflection, and other signs of stress; Hindering desirable vegetative cover (grass cover) and causing embankment erosion; Providing cover for burrowing animals; and, Loosening compacted soil within the dike. Tree and woody vegetation root penetration has a detrimental effect on the performance of earthen and masonry dams. Tree root penetration does not stabilize a soil mass, particularly on an embankment slopes. Quite the contrary, tree root penetration loosens the soil of an embankment slope and creates a condition more conducive to surface water penetration and slope failure. Earthen dams are not unlike other engineered structures in that they must be properly maintained in order to perform as intended in the original design of the structure. Similarly, large tress and heavy vegetation up close to and on stone/masonry structures can also have a detrimental effect on overall safe long term performance of the dam. Page 7 of 10 -Do Not Release -

8 May 1, 2013 Conclusion Overall the Glenwood Lake Dam is in fairly poor condition. Significant corrective maintenance and additional routine maintenance is required to ensure continued safe performance of the dam. In view of the housing located immediately downstream of this dam and the ongoing use of the property for recreational hiking, repair and upgrade of the dam should be given a high priority in order to reduce risk to as low as practical. Recommendations The following recommendations are offered for your consideration. 1. Develop a complete topographic survey of the entire dam. Bathymetry in the reservoir within 200 feet of the dam should also be obtained to define possible sediment build up. This data is essential for establishing reliable dimensions and elevations that are required for an accurate engineering assessment of the dam. 2. Develop and implement a subsurface investigation program to determine dam and foundation properties for stability analysis. This should be implemented within one year. 3. Develop and implement an I&M Plan. This should be implemented within 6 months. 4. Develop and submit to NYSDEC Dam Safety Department an EAP and update the EAP annually. This will require a dam break analysis and preparation of inundation maps for both sunny day and flood in the event of dam failure. This should be implemented within 6 months. 5. Perform an engineering assessment of the dam, which includes an assessment of dam deficiencies, hydrologic and hydraulics analyses (H&H), stability analyses of the structural components of the dam, and a review of the current hazard category. This is required no later than August Develop a plan and schedule for implementation of tree and brush removal on and near the dam. This should be implemented within one year. Page 8 of 10 -Do Not Release -

9 May 1, Develop a plan and schedule for implementation of required rehabilitation of the stone masonry dam. Any repair or construction related to the dam may require permits from the NYSDEC. This should be implemented within one year. What Every Dam Owner Should Know The primary objective of a dam safety program is to ensure the integrity and viability of a dam such that it does not present unacceptable risk to the public, property, the environment and the owner. It requires the collective application of engineering principles and experience. It requires a philosophy of risk management that recognizes that a dam is a structure whose safe functioning is not explicitly determined by its original design and construction. Failure of a dam can have major consequences to the public and to the owners of the dam. Regardless of the regulatory framework under which a dam is being operated, dam owners have ultimate responsibility for the safe operation of this dam. This responsibility exposes owners of dams to substantial risks. Many times dam owners are not aware of the scope of these risks. A dam safety program is one very beneficial approach for dam owners to greatly reduce the risk of a sudden uncontrolled release of water with the potential to cause great harm. The program should include regular visual surveillance, maintenance, and repairs when needed. The need for and value of ongoing maintenance and upgrade programs for dams cannot be underestimated. The owners should act on all dam safety related findings in a prompt manner in order to reduce risk as low as reasonably possible. Without immediate attention, the dam may further deteriorate or may fail under extreme loading events, which can lead to a complete breach and major consequences in many ways. Some potential consequences include the following: Loss of life; Damage to homes, businesses, transportation networks, lifelines, utilities, schools, industrial facilities and other improvements; Damage to the environment; Threat to other dams located downstream that can result in cascade failures; Loss of stored reservoir pool; Loss of use of the dam; Loss of economic benefit from the dam; Page 9 of 10 -Do Not Release -

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11 APPENDIX A PROJECT LOCATION MAP AND SITE PLAN R /13 -Do Not Release-

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14 APPENDIX B DAM SAFETY INSPECTION CHECK LIST R /13 -Do Not Release-

15 ENGINEER S DAM SAFETY INSPECTION CHECKLIST Name of Project: Glenwood Lake Dam, New Rochelle, NY Hazard Classification: B State ID # ; Federal ID # NY13618 Date Inspected: 2/28/13 Type: Masonry; Earth Weather Conditions: 41 F; cloudy, light rain Length: 335 ft (est.) Height: 12 ft Pool spillway crest Spillway Width: 6 ft; Discharge: 18 cfs Tailwater Elevation: N/A Purpose: Recreation Reservoir Max. Storage: 11 acre-feet Reservoir Normal Storage: 7 acre-feet Reservoir Surface Area: 4 acres Drainage Area: 0.12 sq. mi. (Estimated) Names/Titles of Inspecting Engineer: William Broderick, P.E., Principal, Paul C. Rizzo Engineering, Tarrytown, NY Names/Titles of Other Participants: Barry Nechis, Captain, New Rochelle Fire Department, OEM Coordinator, New Rochelle, NY Kaz Orszulik, Senior Engineer, Department of Public Works, New Rochelle, NY ITEMS YES NO REMARKS RESERVOIR x 1. Signs of shoreline instability? x 2. Sedimentation? x 3. Debris? x 4. Ice related problems? x 5. Operating constraints? x 6. Environmental concerns? x 7. Rim stability? x 8. Other? x DOWNSTREAM CHANNEL (Below Project) x Spillway discharges to underground pipe of unknown size. Downstream area is steep slope and discharge location is unknown. Further investigation required. 1. Eroding or backcutting? 2. Sloughing? 3. Obstruction? GEOLOGIC CONDITIONS x No records Comments: Year Completed: unknown Tributary Hutchinson River, Lower Hudson Drainage Basin B-1 -Do Not Release-

16 ENGINEER S DAM SAFETY INSPECTION CHECKLIST Name of Project: Glenwood Lake Dam, New Rochelle, NY Hazard Classification: B State ID # ; Federal ID # NY13618 ITEMS YES NO REMARKS EMERGENCY ACTION PLAN (EAP) x Emergency response plan filed but non-compliant with EAP guidelines. Conforming EAP to be developed. 1. Current plan posted? x 2. Understood by operator? x 3. Warning systems? x 4. Certification of last test? x 5. Remote operation? x 6. Adequate? x 7. Habitable structures? x Steep slopes below spillway with fairly dense residential housing over wide area. 8. Recreation areas? x Lake area and dam crest used by general public 9. Changed hazard potential? x Water storage appears to be limited but d/s residential housing will be adversely affected by dam breach. Potential impacts enhanced by downstream steep slopes. 10. New development? x 11. Other? x OWNER S INSPECTION PROGRAM (I&M Plan) x I&M Plan to be developed. 1. Does one exist? x 2. Adequate surveillance? x a. Project structures? b. Penstocks? c. Conduits through dams? d. Drainage systems? e. Other? 3. Frequency? x 4. Documentation? x 5. Performed by whom? x No one assigned Comments: B-2 -Do Not Release-

17 ENGINEER S DAM SAFETY INSPECTION CHECKLIST Name of Project: Glenwood Lake Dam, New Rochelle, NY Hazard Classification: B State ID # ; Federal ID # NY13618 ITEMS YES NO REMARKS STONE MASONRY DAM x 1. Alignment a. Alignment? x Irregular and generally poor b. Displacement? x Some displacement of stones c. Rotation? x 2. Deterioration x a. Cracking? x Loose & missing stones; deteriorating mortar b. Spalling? x c. Exposed reinforcement? x 3. Seepage x a. Where? x Water ponding at immediate d/s of stone masonry dam section b. Quantity? x no significant flow observed; perforated drain tile directed back into spillway may be blocked 4. Drains x a. Box drain outlets? x b. Weepholes? x 5. Abutment & Foundation Contacts x No construction drawings or sketches available a. Abutment instability? b. Erosion? Visibility poor because of heavy vegetation, shrubs, large trees, & cuttings on upstream and downstream faces. c. Undercutting? d. Visible displacement? e. Seepage from contact? x f. Boils downstream? x unknown g. Springs? x unknown h. Abutment shoreline freeboard? x Lake level within 1 ft of crest 6. Galleries x a. Displacement? b. Deterioration (1) Cracking? (2) Spalling? (3) Exposed reinforcement? (4) Loss of joint fillers? (5) Leakage? (6) Scaling? c. Drains (1) Structure drains? (2) Foundation drains? (3) Maintenance/Inspection program? (4) Gutter deposits? (Continued) B-3 -Do Not Release-

18 ENGINEER S DAM SAFETY INSPECTION CHECKLIST Name of Project: Glenwood Lake Dam, New Rochelle, NY Hazard Classification: B State ID # ; Federal ID # NY13618 ITEMS YES NO REMARKS 7. Instrumentation x a. Are there... (1) Piezometers? (2) Weirs? (3) Settlement monuments? (4) Observation wells? (5) Other? b. Are readings... (1) Available? (2) Plotted? (3) Taken periodically? (4) Submitted periodically? c. Evaluated? d. Adequacy? 8. Other? x Comments: B-4 -Do Not Release-

19 ENGINEER S DAM SAFETY INSPECTION CHECKLIST Name of Project: Glenwood Lake Dam, New Rochelle, NY Hazard Classification: B State ID # ; Federal ID # NY13618 ITEMS YES NO REMARKS SERVICE SPILLWAY x 1. Crest x Crest uneven a. Settlements? x b. Displacements? x c. Cracking? x d. Deterioration? x e. Exposed reinforcement? x 2. Control Structures x a. Mechanical equipment operable? b. Are gates maintained? c. Will flashboards trip automatically? d. Are stanchions trippable? e. Are gates remotely controlled? f. Corrosion? g. Breakage? h. Secure anchorages? i. Operating constraints? j. De-icing system operable? 3. Outlet Works x a. Displacements? b. Cracking? c. Deterioration? d. Exposed reinforcement? e. Seepage at lift lines or joints? f. Weepholes? g. Drains? 4. Approach Channel x a. Trash boom? b. Debris? c. Vegetation and trees? d. Sedimentation? 5. Abutment & Foundation Contacts x a. Abutment instability? b. Erosion? c. Undercutting? d. Visible displacement? e. Seepage from contact? f. Boils downstream? g. Springs? h. Abutment shoreline freeboard? 6. Galleries x a. Displacement? b. Deterioration (1) Cracking? (continued) (2) Spalling? B-5 -Do Not Release-

20 ENGINEER S DAM SAFETY INSPECTION CHECKLIST Name of Project: Glenwood Lake Dam, New Rochelle, NY Hazard Classification: B State ID # ; Federal ID # NY13618 (3) Exposed reinforcement? (4) Loss of joint fillers? (5) Leakage? (6) Scaling? c. Drains (1) Structure drains? (2) Foundation drains? (3) Maintenance/Inspection program? (4) Gutter deposits? 7. Instrumentation x a. Are there: (1) Piezometers? (2) Weirs? (3) Settlement monuments? (4) Observation wells? (5) Other? b. Are readings: (1) Available? (2) Plotted? (3) Taken periodically? (4) Submitted periodically? c. Evaluation? d. Adequacy? 8. Energy Dissipators x a. Deterioration? b. Erosion? c. Exposed reinforcement? 9. Discharge Channel x a. Undercutting? b. Erosion? c. Obstruction? 10. Fuse Plug x a. Deterioration? b. Clear approach channel? c. Clear exit channel? d. Seepage? 11. Gate Tests x a. Auxiliary power? b. Normal power? c. Gate operation certifications/witness? 12. Other x Comment: Spillway is inadequate and cannot be easily rated in terms of discharge capacity. Drain pipe size, condition, and discharge location is unknown. Trickle flow observed at spillway drop structure. B-6 -Do Not Release-

21 ENGINEER S DAM SAFETY INSPECTION CHECKLIST Name of Project: Glenwood Lake Dam, New Rochelle, NY Hazard Classification: B State ID # ; Federal ID # NY13618 ITEM YES NO REMARKS LOW LEVEL OUTLET x 1. Gates x a. Mechanical equipment operable? b. Are gates remotely controlled? c. Are gates maintained? 2. Concrete Conduits x a. Cracking?... b. Deterioration? c. Erosion? d. Exposed reinforcement? e. Are joints displaced? f. Are joints leaking? 3. Metal Conduits x a. Is metal corroded? b. Is conduit cracked? c. Are joints displaced? d. Are joints leaking? 4. Energy Dissipators x a. Deterioration? b. Erosion? c. Exposed reinforcement? 5. Metal Appurtenances x a. Corrosion? b. Breakage? c. Secure Anchorages 6. Discharge Channel x a. Undercutting? b. Erosion? c. Obstruction? d. Other? 7. Sealed Conduits x a. Location? b. Properly maintained? Comments: B-7 -Do Not Release-

22 ENGINEER S DAM SAFETY INSPECTION CHECKLIST Name of Project: Glenwood Lake Dam, New Rochelle, NY Hazard Classification: B State ID # ; Federal ID # NY13618 ITEMS YES NO REMARKS INTAKES x 1. Equipment a. Trash boom? b. Trash racks? c. Trash rake? d. Mechanical equipment operable? e. Intake gates? f. Are racks and gates maintained? 2. Concrete Surfaces a. Cracking?... b. Deterioration? c. Erosion? d. Exposed reinforcement? e. Are joints displaced? f. Are joints leaking? 3. Conduits a. Cracking? b. Deterioration? c. Erosion? d. Exposed reinforcement? e. Are joints displaced? f. Are joints leaking? 4. Power Canals & Locks a. Slope protection? b. Trees & Brush? c. Erosion? d. Seepage? e. Animal burrows? f. Buried conduits? g Wall deterioration? 5. Metal Appurtenances a. Corrosion? b. Breakage? c. Secure Anchorages? 6. Penstocks a. Materials deteriorated? b. Joints Leaking? c. Supports adequate? d. Anchor blocks stable? Comments: B-8 -Do Not Release-

23 ENGINEER S DAM SAFETY INSPECTION CHECKLIST Name of Project: Glenwood Lake Dam, New Rochelle, NY Hazard Classification: B State ID # ; Federal ID # NY13618 ITEMS YES NO REMARKS POWERHOUSE x 1. Are generating units operable? 2. Any shutdowns since last inspection? 3. Is auxiliary equipment operable? 4. Proper maintenance? 5. Deterioration a. Cracking? b. Spalling? c. Exposed reinforcement? d. Loss of joint fillers? 6. Galleries a. Displacement? b. Deterioration (1) Cracking? (2) Spalling? (3) Exposed reinforcement? (4) Loss of joint fillers? (5) Leakage? (6) Scaling? c. Drains (1) Structure drains? (2) Foundation drains? (3) Maintenance/Inspection program? (4) Gutter deposits? 7. Any changes to structure? 8. Any changes to equipment? 9. Instrumentation? a. Are there... (1) Piezometers? (2) Weirs? (3) Settlement monuments? (4) Observation wells? (5) Other? b. Are readings... (1) Available? (2) Plotted? (3) Taken periodically? (4) Submitted periodically? c. Evaluation? d. Adequacy? 10. Other? B-9 -Do Not Release-

24 ENGINEER S DAM SAFETY INSPECTION CHECKLIST Name of Project: Glenwood Lake Dam, New Rochelle, NY Hazard Classification: B State ID # ; Federal ID # NY13618 ITEMS YES NO REMARKS EARTHEN EMBANKMENT x 1. Alignment a. Alignment? x Irregular alignment b. Displacement? x c. Settlement? x Crest uneven; side slopes not accessible 2. Deterioration a. Erosion? b. Sloughs or Slumps? c. Riprap? 3. Seepage a. Where? b. Quantity? 4. Abutment Contacts a. Abutment instability? b. Erosion? c. Undercutting? d. Visible displacement? e. Seepage from contact? f. Boils downstream? g. Springs? h. Abutment shoreline freeboard? 5. Instrumentation a. Are there... (1) Piezometers? (2) Weirs? (3) Settlement monuments? (4) Observation wells? (5) Other? b. Are readings... (1) Available? (2) Plotted? (3) Taken periodically? (4) Submitted periodically? c. Evaluated? b. Adequacy? 6. Other? Comments: Excessive vegetation, large trees, dead fall, cuttings dumped downslope make access difficult. Unable to fully inspect embankment slopes. Danger trees, possible damaged during Sandy, should be removed for public safety. B-10 -Do Not Release-

25 APPENDIX C INSPECTION PHOTOGRAPHS -Do Not Release-

26 APPENDIX C PHOTOGRAPHS GLENWOOD LAKE DAM NYSDEC ID # PHOTO 1: GLENWOOD LAKE DAM FROM LEFT ABUTMENT; LARGE TREES AND SHRUBS UPSTREAM AND DOWNSTREAM FEBRUARY 28, 2013 PHOTO 2: GLENWOOD LAKE DAM FROM SPILLWAY TOWARD LEFT ABUTMENT; LOOSE/MISSING STONES NOTED FEBRUARY 28, 2013 C-1 Do Not Release

27 APPENDIX C PHOTOGRAPHS GLENWOOD LAKE DAM NYSDEC ID # PHOTO 3: RESERVOIR LOOKING UPSTREAM FEBRUARY 28, 2013 PHOTO 4: RESERVOIR RIM FEBRUARY 28, 2013 C-2 Do Not Release

28 APPENDIX C PHOTOGRAPHS GLENWOOD LAKE DAM NYSDEC ID # PHOTO 5: SPILLWAY SEEPAGE THROUGH JOINTS; EROSION AT ABUTMENTS FEBRUARY 28, 2013 PHOTO 6: SPILLWAY CREST: LOOSE STONES, UNEVEN; SPILL TRANSITIONS TO UNDERGROUND PIPE FEBRUARY 28, 2013 C-3 Do Not Release

29 APPENDIX C PHOTOGRAPHS GLENWOOD LAKE DAM NYSDEC ID # PHOTO 7: EMBANKMENT LOOKING NORTH & ENDING AT GLOUCESTER ROAD. EXCESSIVE LARGE TREES AND VEGETATION ON UPSTREAM AND DOWNSTREAM SLOPES FEBRUARY 28, 2013 PHOTO 8: EMBANKMENT LOOKING SOUTH TOWARD SPILLWAY. EXCESSIVE LARGE TREES AND VEGETATION ON UPSTREAM AND DOWNSTREAM SLOPES FEBRUARY 28, 2013 C-4 Do Not Release

30 APPENDIX C PHOTOGRAPHS GLENWOOD LAKE DAM NYSDEC ID # PHOTO 9: DUMPED VEGETATION DOWNSTREAM OF SPILLWAY FEBRUARY 28, 2013 PHOTO 10: DOWNSTREAM OF SPILLWAY FEBRUARY 28, 2013 C-5 Do Not Release

31 APPENDIX C PHOTOGRAPHS GLENWOOD LAKE DAM NYSDEC ID # PHOTO 11: DAM & SPILLWAY. NOTE SEEPAGE THROUGH MASONRY DAM FEBRUARY 28, 2013 C-6 Do Not Release