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(continued) ation. Instruments which have been installed to measure behavior of the structures should be examined for proper functioning. The available records and readings of installed instruments should be reviewed to detect any unusual performance of the instruments or evidence of unusual performance or distress of the structure. The adequacy of the installed instrumentation to measure the performance and safety of the dam should be determined.
a. Headwater and Tailwater Gages. The existing records of the headwater and tailwater gages should be examined to determine the relationship between other instrumentation measurements such as stream flow, uplift pressures, alignment, and drainage system discharge with the upper and lower water surface elevations.
b. Horizontal and Vertical Alignment Instrumentation (Concrete Structures). The existing records of alignment and elevation surveys and measurements from inclinometers, inverted plumb bobs, gage points across cracks and joints, or other devices should be examined to determine any change from the original position of the structures.
c. Horizontal and Vertical Movement, Consolidation, and Pore-Water Pressure Instrumentation (Embankment Structures). The existing records of measurements from settlement plates or gages, surface reference marks, slope indicators and other devices should be examined to determine the movement history of the embankment. Existing piezometer measurements should be examined to determine if the pore-water pressures in the embankment and foundation would under given conditions impair the safety of the dam.
d. Uplift Instrumentation. The existing records of uplift measurements should be examined to determine if the uplift pressures for the maximum pool would impair the safety of the dam.
e. Drainage System Instrumentation. The existing records of measurements of the drainage system flow should be examined to establish the normal relationship between pool elevations and discharge quantities and any changes that have occurred in this relationship during the history of the project.
f. Seismic Instrumentation. The existing records of seismic instrumentation should be examined to determine the seismic activity in the area and the response of the structures of past earthquakes.
6. Reservoir. The following features of the reservoir should be examined to determine to what extent the water impounded by the dam would constitute a danger to the safety of the dam or a hazard to human life or property.
a. Shore line. The land forms around the reservoir should be examined for indications of major active or inactive landslide areas and to determine susceptibility of bedrock stratigraphy to massive landslides of sufficient magnitude to significantly reduce reservoir capacity or create waves that might overtop the dam.
b. Sedimentation. The reservoir and drainage area should be examined for excessive sedimentation or recent developments in the drainage basin which could cause a sudden increase in sediment load thereby reducing the reservoir capacity with attendant increase in maximum outflow and maximum pool elevation.
c. Potential Upstream Hazard Areas. The reservoir area should be examined for features subject to potential backwater flooding resulting in loss of human life or property at reservoir levels up to the maximum water storage capacity including any surcharge storage.
d. Watershed Runoff Potential. The drainage basin should be examined for any extensive alterations to the surface of the drainage basin such as changed agriculture practices, timber clearing, railroad or highway construction or real estate developments that might extensively affect the runoff characteristics. Upstream projects that could have impact on the safety of the dam should be identified.
7. Downstream Channel. The channel immediately downstream of the dam should be examined for conditions which might impose any constraints on the operation of the dam or present any hazards to the safety of the dam. Development of the potential flooded area downstream of the dam should be assessed for compatibility with the hazard classification.
8. Operation and Maintenance Features.
a. Reservoir Regulation Plan. The actual practices in regulating the reservoir and discharges under normal and emergency conditions should be examined to determine if they comply with the designed reservoir regulation plan and to assure that they do not constitute a danger to the safety of the dam or to human life or property.
b. Maintenance. The maintenance of the operating facilities and features that pertain to the safety of the dam should be examined to determine the adequacy and quality of the maintenance procedures followed in maintaining the dam and facilities in safe operating condition.
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Appendix E to §222.6—Suggested Outline
Inspection Report—National Dam Inspection Program (RCS-DAEN-CWE–17 and OMB No. 49–R0421)
Title Sheet
Name of Dam
ID Number from Inventory
State, County and River or Stream where dam is located
Owner
Size and Hazard Classification
Names of Inspectors
Names of Review Board
Approval Signature of District Engineer
Table of Contents
General Assessment
Give brief assessment of general condition of dam with respect to safety, including a listing of deficiencies, and recommendations indicating degree of urgency.
1. Introduction
a. Authority
b. Purpose and Scope of Inspection
2. Project Information
a. Site Information
b. Description of Structures—Dam, Outlet, Spillway and other principal features.
c. Purpose of Dam
d. Design, Construction and Operating History
3. Field Inspection
Briefly describe physical condition of the dam and appurtenant structures as they were observed during the field inspection. (If field inspection form is appended, only present summary.) Describe operational procedures, including any warning system, condition of operating equipment, and provision for emergency procedures. Describe any pertinent observations of the reservoir area and downstream channel adjacent to dam.
4. Evaluation
a. Structural and Geotechnical
(1) General
(2) Embankment and/or Foundation Condition
(3) Stability—Briefly discuss pertinent information such as design, construction and operating records. Assess stability under maximum loading on basis of the record data, together with observations of field inspection and results of any additional, brief calculations performed by inspectors. If additional, detailed stability analyses are considered necessary, recommend that the owner engage a qualified engineer or firm to provide the analysis.
b. Hydrologic and Hydraulic
(1) Spillway Adequacy—Briefly describe pertinent record information such as hydrologic and hydraulic design data, flood of record, and previous analyses. Describe any hydraulic and hydrologic analyses made for this inspection. Present conclusion with respect to adequacy of spillway to pass the recommended spillway design flood without overtopping dam. If overtopping would occur, and if available from the type of analysis used, give maximum depth over top of dam and duration of overtopping, assuming the dam does not fail. Also indicate the largest flood, as a percentage of the probable maximum flood which can be passed without overtopping.
(2) Effects of overtopping—If dam is overtopped by the recommended spillway design flood, provide assessment as to whether or not dam would likely fail, and if, in case of failure, the hazard to loss of life downstream of the dam would be substantially increased over that which would exist without failure. If information upon which to base a reasonable assessment is insufficient, so state and describe the needed data, and recommend that the necessary studies be performed by engineers engaged by the owner.
c. Operation and Maintenance
Assess operating equipment and procedures, emergency power for gate operation, and Emergency Action Plan. Assess quality of maintenance as it pertains to dam safety.
5. Conclusions
Provide conclusions on condition of dam and list all deficiencies. If dam is considered unsafe, so state and give reason.
6. Recommendations
List all recommended actions, including additional studies, installation of new surveillance procedures and devices, development of Emergency Action Plans, and remedial work. Recommend that a qualified engineering firm be retained to accomplish any recommended additional investigations and studies and also to design and supervise remedial works.
Appendixes
a. Inspection Checklist (if available)
b. Other Illustrations as follows:
(1) Include a map showing location of the dam. Usually a portion of a USGS quadrangle sheet can be used which will show the topography of the area, location of the dam, exent of the lake and drainage basin, and perhaps indicate the downstream development.
(2) If available, include a plan and section of the dam.
(3) General photographs of the dam and downstream channel should be included.
(4) Color photographs of deficiencies should be included. These should be held to the minimum required to illustrate the deficiencies.
(5) Available engineering data including Hydrologic/Hydraulic calculation and physical test results that might be available.
Appendix F to §222.6
Instructions for Unsafe Dam Data Sheet (RCS-DAEN-CWE-17 and OMB No. 49–R0421)
The indicated information shall be provided in the format shown on Pg F–3 for each dam assessed to be unsafe during the reporting period. A separate data sheet should be provided for each unsafe dam. The information supplied should conform to the following.
a. Name—Name of dam.
b. Id. No.—Dam inventory identity number.
c. Location—List state county, river or stream and nearest D/S city or town where the dam is located.
d. Height—Maximum hydraulic height of dam.
e. Maximum Impoundment Capacity—List the capacity of the reservior at maximum attainable water surface elevation including any surcharge loading.
f. Type—Type of dam, i.e., earth, rockfill, gravity, combination earth-gravity, etc.
g. Owner—Owner of dam.
h. Date Governor Notified of Unsafe Condition—The date and method of notification, such as, by telegram, letter, report, etc.
i. Condition of Dam Resulting in Unsafe Assessment—Brief description of the deficiencies discovered which resulted in the unsafe assessment.
j. Description of Danger Involved—Downstream (D/S) hazard potential category and a brief description of the danger involved.
k. Recommendations Given to Governor—Brief description of the actions recommended to Governor at time of notification of unsafe condition to eliminate or reduce the danger.
l. Urgency Category—State whether the unsafe condition of the dam is an emergency or non-emergency situation. An emergency situation should be considered to exist if the failure of the dam is judged to be imminent and requires immediate action to eliminate or reduce the danger.
m. Emergency Actions Taken—In case of an emergency situation, list the actions taken. For non-emergency situation, put NA for “not applicable.”
n. Remedial Action Taken—For non-emergency situations list remedial actions taken.
o. Remarks—For other pertinent information.
Format for Unsafe Dam Data Sheet (RCS-DAEN-CWE-17 and OMB No. 49–R0421
National Program of Inspection of Non-Federal Dams—Unsafe Dam Data Sheet
a. Name:
b. Type:
c. Height:
d. Id. No.
e. Location:
State: County:
Nearest D/S City, Town or Village:
River or Stream:
f. Owner:
g. Date Governor Notified of Unsafe Condition:
h. Condition of Dam Resulting in Unsafe Assessment:
i. Description of Danger Involved:
j. Recommendations Given to Governor:
k. Urgency Category:
l. Emergency Actions Taken:
m. Remarks:
Appendix G to §222.6
National Program for Inspection of Non-Federal Dams—Monthly Progress Report (RCS-DAEN-CWE-19)
I. Instructions for Monthly Progress Report. The indicated information shall be provided in the format shown on page G–2.
1. Division Reporting:
2. Date:
3. Information Required for Each State Regarding Total Number of Inspections Performed (AE Inspections included) (Cumulative):
3.1. Number of Inspections Initiated by on-site inspection or the review of engineering data from project records. 1
1 Each of the initiated inspections reported should be planned for completion within a reasonable period of time (30 days.)
3.2. Number of Inspections Competed (The number of inspection reports which have been submitted to the District Engineer for review and approval).
3.3 Number of Dams Reported to the Governor as Unsafe. 2
2 An unsafe dam is defined as a dam with deficiencies of such a nature that if not corrected could result in the failure of the dam with subsequent loss of lives or substantial property damage.
3.4. Number of Approved Inspection Reports Submitted to the Governor.
4. Information Required for Each State Regarding Inspections Performed Under AE Contracts (Cumulative):
4.1. Number of Dams Contracted for Inspection by AE's with State or Corps.
4.2. Number of Inspections Initiated by AE's by on-site inspection or the review of engineering data from project records. 1
1 See footnote on previous page.
4.3. Number of Inspections Completed by AE's (The number of inspection reports which have been submitted to the District Engineer for review and approval).
4.4. Number of Approved Inspection Reports Prepared by AE's Submitted to the Governor.
II. Formation for Monthly Progress Report.
National Program for Inspection of Non-Federal Dams—Monthly Progress Report
1. Division Reporting:
2. Date:
3. Information Required for Each State Regarding Total Number of Inspections Performed (Cumulative):
------------------------------------------------------------------------
Unsafe
Inspection Inspection Dams Approved
State Initiated Completed Reported Reports
(3.1) (3.2) (3.3) (3.4)
------------------------------------------------------------------------
===========================================
Total.......................
------------------------------------------------------------------------
4. Information Required for Each State Regarding Inspections Performed Under A/E Contracts (Cumulative):
----------------------------------------------------------------------------------------------------------------
Dams
Under A/ A/E A/E A/E
State E Inspections Inspections Reports
Contract Initiated Completed Approved
(4.1) (4.2) (4.3) (4.4)
----------------------------------------------------------------------------------------------------------------
=============================================
Totals............................................................
----------------------------------------------------------------------------------------------------------------
Appendix H to §222.6
Suggested Scope of Work Contract for Architect-Engineer Services for Safety Inspection of Dams Within the State of ____
1. General Description of Scope of Work. The services to be rendered by the Architect-Engineer (AE) under the proposed contract shall include all engineering functions, hereinafter described, as needed to inspect the dams listed in Appendix A of this contract for the purpose of evaluating their risk of failure. A report which (a) describes the assessed condition of the dam, (b) provides conclusions as to which particular conditions could cause failure, (c) makes recommendations on remedial measures believed necessary, and (d) makes recommendations on whether and what type of future investigation should be conducted shall be provided for each inspected dam. The work shall proceed in accordance with Phase I of the Recommended Guidelines for Safety Inspection of Dams established by the Office of the Chief of Engineers (OCE) and the supplemented requirements listed in paragraph 3 below. The OCE guidelines are listed in Appendix B of this contract.
2. Information and Services To Be Furnished by the Government. The Contracting Officer will furnish the following information and services to the AE:
a. All information pertaining to each dam to be inspected as contained in the National Inventory of Dams.
b. Copies of recommended format for preparation of inspection report, engineering data check list and visual inspection check list.
c. All available pertinent information pertaining to the Dam Inspection Program and previous investigations having a bearing on inspections to be performed under this contract.
d. Right-of-entry for access to each dam site.
3. Services To Be Rendered by the Architect-Engineer. The principal services, subject to the optional provisions of the contract, to be rendered by the AE are itemized below:
a. Technical Investigations.
(1) Engineering Data Collection. To the extent feasible, the engineering data listed in Appendix I of the OCE guidelines relating to the design, construction and operation of the dam and appurtenant structures, should be collected from existing records and reviewed to aid in evaluating the general condition of each dam, including an assessment of the hydraulic and hydrologic features and structural stability of the dam. Where the necessary engineering data are unavailable, inadequate or invalid, a listing shall be made of those specific additional data deemed necessary by the engineer in charge of the investigation and included in the inspection report. The engineering data checklist provided by the Contracting Officer shall be used as a guide to compile this data.
(2) Field Inspections. The field inspection of each dam shall include examination of the items listed in Appendix II of the OCE guidelines, electrical and mechanical equipment for operation of the control facilities, reservoir area, downstream channel in the vicinity of the dam and any other significant feature to determine how these features affect the risk of failure of the dam. The inspection shall be conducted in a systematic manner to minimize the possibility of any significant feature being overlooked. The visual inspection checklist provided by the Contracting Officer shall be used as a guide to document the examination of each significant feature.
Particular attention shall be given to detecting evidence of leakage, erosion, seepage, slope instability, undue settlement, displacement, tilting, cracking, deterioration, and improper functioning of drains and relief wells. The degree and quality of maintenance and regulating procedures for operation of the control facilities shall be assessed. The design and existing condition of such control facilities (i.e., spillway, outlet works, etc.) shall be evaluated. An assessment of the degree of siltation that is evident and its effect on the dam's reservoir shall be performed. Photographs and drawings should be used to record conditions in order to minimize written descriptions.
(3) Engineering Analyses.
(a) Evaluation of Hydraulic and Hydrologic (H&H) Features. Evaluation of the hydraulic and hydrological features of each dam shall be based on criteria set forth in the OCE guidelines. If it is determined that the available H&H data are insufficient, the Contracting Officer must be so informed and may exercise an option of requiring the AE to perform an overtopping analysis at additional agreed-upon compensation. The methodology to be used by the AE for this analysis will be based on the OCE guidelines and subject to the approval of the Contracting Officer.
(b) Evaluation of Structural Stability. The evaluation of structural stability of each dam is to be based principally on existing conditions as revealed by the visual inspection, available design and construction information, and records of performance. The objectives are to determine the existence of conditions, identifiable by visual inspection or from records, which may pose a high risk of failure and to formulate recommendations pertaining to the need for any remedial improvements, additional studies, investigations, or analysis. The results of this phase of the inspection must rely substantially upon the experience and judgment of the inspecting engineer. Should it be determined that sufficient data are not available for a reasonable evaluation of the structural stability of a dam and appurtenances, the Contracting Officer should be informed which information is required prior to attempting to evaluate the risk of failure of the dam.
(c) Evaluation of Operational Features. Where critical mechanical/electrical operating equipment is used in controlling the reservoir of a dam, an evaluation of the operational characteristics of this equipment from the standpoint of risk of failure must be performed.
(d) Evaluation of Reservoir Regulation Plan and Warning System. The operational characteristics of each dam's existing reservoir regulation plan and warning system in event of a threatened failure shall be investigated.
b. Emergency Situations. The Contracting Officer must be immediately notified of any observed condition which is deemed to require immediate remedial action. After being notified, the Contracting Officer will contact the appropriate State personnel and will meet the AE at the site to determine the appropriate course of action. This will not relieve the AE of his responsibility to prepare a comprehensive inspection report at the earliest practicable date.
c. Qualifications of Investigators. The technical investigations shall be conducted by licensed professional engineers with a minimum of five years experience after licensing in the investigation, design and contruction of earthfill, rockfill and concrete dams and/or in making risk of failure evaluations of completed dams. These engineers must be knowledgeable in the disciplines of hydrology, hydraulics, geotechnical, electrical, mechanical and structural engineering, as necessary. All field inspections should be conducted by engineers, engineering geologists and other specialists who are knowledgeable in the investigation, design, construction and operation of dams, including experts on mechanical and electrical operation of gates and controls, where needed.
d. Preparation of Report. A formal report shall be prepared for each dam inspected for submission to the Contracting Officer. Each report should contain the information specified in OCE guidelines and any other pertinent information. The recommended format provided by the Contracting Officer shall be used to document each report. The signature and registration identification of the professional engineer who directed the investigation and who was responsible for evaluation of the dam should be included in the report.
4. Supervision and Approval of Work. All work performed under this contract shall be subject to the review and approval of the Contracting Officer or his designee. Meetings will be held on a regular basis in the District office, during which the progress of inspections will be discussed and questions relating to inspection reports previously received by the Contracting Officer will be addressed. Reports will be revised as necessary when required by the Contracting Officer.
5. Coordination. During the progress of work, the AE shall maintain liaison with the * ____ and other local authorities through the Contracting Officer as required to assure the orderly progression of the inspection. Copies of all correspondence with such authorities shall be provided to the Contracting Officer.
*Note: Write in the designated State Authority.
6. Submission of Report.
a. Each inspection report will be submitted for review to the Contracting Officer. Reports will be revised as required by the Contracting Officer. After all revisions have been made, the original and __ copies of each inspection report shall be submitted to the Contracting Officer.
b. Text of all reports shall be typewritten and printed on both sides of 8&inch;×10 1/2&inch; paper. All notes, inspection forms, sketches or similar matter shall be legible, distinct and suitable for reproduction.
7. Period of Services.
a. All inspections and reports included under this contract shall be completed within __ days from date of Notice to Proceed.
b. If the option for performing an H&H analysis for any particular site is exercised, the AE shall complete such analysis within __ days from date of Notice to Proceed. However, the overall completion time stated in paragraph 7a above shall not change.
Appendix I to §222.6
Procedure for Using NASA Land Satellite Multispectral Scanner Data for Verification and Updating the National Inventory of Dams
1. Purpose. This appendix states the objective, defines the scope, prescribes procedures, and assigns responsibilities for using NASA Land Satellite (LANDSAT) Multispectral Scanner data along with NASA's Surface Water Detection And Mapping (DAM) Computer program to assist in verification and updating the National Inventory of Dams.
2. Applicability. This appendix is applicable to all divisions and districts having Civil Works responsibilities except POD.
3. Reference. NASA, DETECTION AND MAPPING PACKAGE, Users Manuals, Volumes 1, 2a, 2b, and 3 dated June 1976, published by the Johnson Space Center, Houston, Texas.
4. Objectives. Provide a uniform method, nation-wide, to help insure that all dams subject to Public Law 92–367, 8 August 1972 are properly identified and located in the National Inventory of Dams.
5. Scope. The computer printer overlay maps produced by the procedure described in reference 3b will be used by district and/or state or contractor personnel as a tool to assist in verification and updating of the National Inventory of Dams.
6. Exceptions. a. If a Division/District attempts the use of the procedure for a given region within their area of responsibility and finds the overlay maps cannot be used to assist in verification and updating the National Inventory of Dams, they may request an exception for a selected region. A selected region may include areas where conditions can reasonably be assumed to be the same as the region where the procedure was tried.
b. Request for exceptions should be documented to include firm boundary definitions and appropriate justification to demonstrate why the procedure cannot be used. This request should be submitted to WRSC WASH DC 20314, through the normal engineering chain of command.
c. Map overlays will be produced for all areas of the Continental United States even if they are not used in a few selected regions. This processing is required for a future Computer Water Body Change Detection system.
7. Procedures. Acquisition of LANDSAT data, registration of satellite coordinates to earth latitude and longitude and computer processing to produce overlay maps will be accomplished by two Regional Centers. Nashville District and Seattle District have been designated as the Regional Centers, with each responsible for processing maps by state based on Divisional assignments in Appendix A. Regional Centers will support divisions as follows:
------------------------------------------------------------------------
Regional Center Division
------------------------------------------------------------------------
Nashville District New England
North Atlantic
South Atlantic
Ohio River
Lower Mississippi Valley
North Central
Seattle District Southwestern
Missouri River
North Pacific
South Pacific
------------------------------------------------------------------------
8. Responsibilities. a. The Water Resources Support Center at Fort Belvoir has overall responsibility for coordination and monitoring of this activity between NASA, Division Offices, and Regional Centers, and for providing Regional Center funding.
b. Regional Centers are responsible for:
(1) Acquiring proper LANDSAT data tape from EROS Data Center (Sioux Falls, South Dakota). Actual data scene selection will be coordinated with Division and/or District to insure proper consideration is given to local priorities and seasonal coverage.
(2) Arranging computer processing support using NASA's DAM package.
(3) Establishing proper control between satellite scanner-oriented coordinates and earth latitude/longitude.
(4) Producing total coverage of map overlays at a scale of 1:24,000 and/or smaller scales as required by Divisions and/or Districts.
(5) Instructing District, State, or contractor personnel in the assembly and use of map overlays.
c. Divisions/Districts are responsible for:
(1) Designating one person from each Division and District as the point of contact with the Regional Center and provide this person's name and phone number to the Regional Center.
(2) Providing the Regional Center with map coverage of their area of responsibility. This will include state indexes and 7 1/2 minute quadrangle sheets (scale 1:24,000) where available.
(3) Coordinating with the Regional Center in selecting LANDSAT data tapes.
(4) Providing information to Regional Center on scale and priorities of desired computer produced map overlays.
(5) Assembling computer print-outs into overlay maps, and using as appropriate to assist in verification and updating the National Inventory of Dams.
9. Points of Contact. The points of contact in the Regional Centers for this program are as follows:
Name, Office Symbol, and Telephone
Jim Cook—DAEN-ORNED, (615) 251–7366; FTS 852–7366.
Jack Erlandson—DAEN-NPSEN, (206) 764–3535; FTS 399–3535.
[44 FR 55336, Sept. 26, 1979, as amended at 45 FR 18925, Mar. 24, 1980. Redesignated at 60 FR 19851, Apr. 21, 1995]