UNITED STATES DEPARTMENT OF AGRICULTURE
Rural Utilities Service
SUBJECT: System Planning Guide, Construction Work Plans
TO: RUS Electric Borrowers and RUS Electric Staff
EFFECTIVE DATE: Date of Approval.
EXPIRATION DATE: Seven years from effective date.
OFFICE OF PRIMARY INTEREST: Distribution Branch, Electric Staff Division.
INSTRUCTIONS: This Bulletin is a revision of RUS Bulletin 1724D-101B, "System Planning Guide, Construction Work Plans," dated April 14, 1993.
AVAILABILITY: This Bulletin, and any other RUS bulletin mentioned herein, is available on the RUS electric web page at: http://www.usda.gov/rus/electric/index.htm.
PURPOSE: The purpose of this bulletin is to provide guidance to borrowers and engineers in the preparation of construction work plans (CWPs) for electric distribution systems. A CWP is the documented results of an engineering study which has determined all of the new construction required to provide adequate and reliable electric service during the planning period. A CWP is used as an engineering support document for a loan application, as a component of ongoing integrated system planning, and as means for specifying and documenting plant requirements for the next 2 to 4 years.
REVISIONS: The following significant changes were made during the update of this bulletin:
|/s/ Alfred Rodgers (for)||10/31/00|
TABLE OF CONTENTS
1. Use Of Construction Work Plan:
3. Determining Construction Requirements:
4. The Construction Work Plan Report:
5. Environmental Reports:
6. Construction Work Plan Amendments:
7. Approval Of Construction Work Plans:
Exhibit A: TABLE OF CONTENTS (Typical Construction Work Plan)
Exhibit B: RUS CONSTRUCTION CODES
System Planning Guide
Long-Range System Plan
Construction Work Plans
|AMR||Automatic Meter Reading|
|CFR||Code of Federal Regulations|
|CWP||Construction Work Plan|
|G & T||Generation and Transmission Cooperative|
|GFR||General Field Representative|
|O & M||Operations and Maintenance|
|OCR||Oil Circuit Recloser|
|RUS||Rural Utilities Service|
|SCADA||Supervisory Control and Data Acquisition|
The CWP process is used to determine and document a borrower’s 2 to 4 year construction needs that are the most feasible, environmentally acceptable, and economical. New construction is periodically required in order to provide and maintain adequate and reliable electric service to all of a system's new and existing members. The CWP should include all recommended electric plant facilities regardless of the financing source (general funds, RUS, or all other lenders). A CWP is a valuable reference for the preparation of annual construction budgets and schedules. The CWP report is also used as an engineering support document for a loan application to finance a proposed construction program. As such, the CWP is used as a means to inform RUS and receive RUS's approval of proposed new construction items.2. PREPARATION
The first step in the CWP preparation or development process usually involves a meeting among the system’s management, the system's staff or consulting engineer, the RUS General Field Representative (GFR), and perhaps the borrower’s power supplier. An agreement should be reached at this meeting on the new CWP's planning period, projected maximum loads and number of consumers, and other technical items as presented in this section. At this time, an agreement should also be reached on dates and type of data to be furnished to the engineer, the target completion date of the CWP and future dates of any coordination, and CWP draft review meetings.
2.1 To Be Reviewed : The following data and studies need to be reviewed, analyzed, and updated by the planning engineer.
2.1.1 Historical system data such as energy purchases and sales, losses, peak kW demands, and number of consumers need to be tabulated. This information is generally included in the CWP as reference information but not used in the CWP analysis.
2.1.2 System design criteria has to be established. This criteria identifies the standards within which the system must perform. The design criteria becomes the basis for defining and identifying problems on the system and for justifying necessary improvements. The design criteria should address all aspects of the system that are to be analyzed. All design criteria should be documented and included in the CWP. The system management, engineer, and GFR should agree upon the design criteria before development of the CWP study begins.
188.8.131.52 RUS recommends that the following values be included in the design criteria:
Power Transformers – 105% of nameplate rating;
Substation and Line Voltage Regulators – 100% of nameplate rating;
Oil Circuit Reclosers – 70% of nameplate rating;
184.108.40.206 The list in Section 220.127.116.11 is not inclusive of all criteria that can or should be used. Design criteria should address deficient system components such as deteriorated poles and equipment, inadequate clearances, safety and code violations, and define the type of construction to be used as the system standard. The types of problems documented and the numerical quantities addressed will be somewhat different for each distribution system.
2.1.3 The system's currently approved load forecast (formerly referred to as a Power Requirements Study) needs to be reviewed. The projected system peak kW loads and number of consumers for the CWP planning period should be derived directly from this load forecast. However, for analysis and needed construction purposes, individual historical peak substation demands should be used. Any loads and numbers of consumers used that are not consistent with the load forecast projections need to be explained in the CWP.
2.1.4 The system's currently approved Long Range Plan (LRP) needs to be analyzed to ascertain that its basis (load projections, economic factors, etc.) are still valid for the CWP planning period and also that its construction recommendations are still required, feasible, and economically sound. It is appropriate to include a thorough, yet concise, written review of the LRP in the CWP, including a comparison of historical projected versus actual peak loads. A written summary of the overall recommendations of the LRP helps the reader understand how new recommended construction items conform to the projected development of the system.
2.1.5 Previous CWP and CWP amendments need to be reviewed to determine which projects have been or will be completed and which construction items need to be carried over into the current CWP. Carryover items may need new cost estimates and occasionally may need additional justification. The status of the construction items of the previous CWP can be explained succinctly with a table.
2.1.6 The engineer should use the system's most recent Operations and Maintenance (O&M) survey with its associated "Review Rating Summary" (RUS Form 300) to determine the condition of system components such as poles and conductors, outages, and tree trimming. This summary may also be used to justify the need of new construction items and programs to correct those areas where the system does not meet the design criteria. The O & M survey should be appropriately updated and analyzed to assure that it describes the system’s present conditions. A new O & M survey should be performed before beginning the CWP if the present survey is more than 3 years old. A concise written analysis of the O & M survey and results, and any recommendations contained in the survey, should be included in the CWP. This analysis should contain enough details to explain deficiencies found on the system and the work required to correct them.
2.1.7 All other relevant studies recently performed on the system, such as sectionalizing, system aging, and power factor correction, should be reviewed in detail and compared to the requirements of the design criteria. All present and projected deficiencies on the system should be documented in the CWP to explain the problems found and the construction required to resolve them. Narratives and tables may be used to explain and justify recommended construction.
2.1.8 Periodic system data and reports, such as substation maintenance reports and mini-max voltmeter readings, should be tabulated, analyzed, and compared in detail to the design criteria. All data that is included in the CWP report should be summarized in a concisely written narrative or table. Only include data used to define problems or explain and justify proposed construction items.
2.1.9 The system's service interruption record for the previous 5 years should be analyzed, and summarized in a table and included in the CWP. The CWP narrative should address findings of the interruption analysis and major outages should be explained in adequate detail.
2.1.10 The following maps, data, and information need to be gathered, updated, analyzed, tabulated, and documented as appropriate:
This information is also useful as exhibits in the CWP to explain recommended construction items or projects.
2.1.11 It is suggested that the engineer interview line crews, warehouse personnel, and others who have first hand knowledge of deficiencies on the system or problems with equipment. All reported deficiencies should be corroborated before recommending construction items in the CWP.3. DETERMINING CONSTRUCTION REQUIREMENTS
3.1 New Consumers: The projected number of new consumers is interpolated from the system's load forecast. The number of new consumers, line distances, equipment, and cost data from the past several years is used to project needed construction and its cost to provide service to new consumers to be added during the time period covered by the CWP. The cost to add known new large power usage members to the system during the CWP coverage period should also be added to these totals.
3.2 Historical Data: Use historical data to determine the number and associated costs for the necessary replacements of service drops, transformers, and meters in order to maintain adequate service to existing members.
3.3 System Peak Demand: Projected total system peak demands are also interpolated from the load forecast. The totals may be modified, with explanation, to include recently attained new load data. The engineer should apply appropriate growth and diversity factors to individual circuits and substations so that the total loads are in agreement with the load forecast projections. Loading tables, which show equipment capacities, projected circuit and substation transformer loads, new load additions, load transfers, and new construction projects should be included in the CWP. These loading tables are used to determine and show substation equipment which is anticipated to be loaded above the design criteria.
3.4 Anticipated Loads: Each of the system's distribution circuits, updated to include anticipated new loads and circuit changes, should be analyzed at its projected peak load for the entire CWP planning period. The primary voltage drop at each circuit node, the thermal loading of all circuits’ conductors and equipment, circuit power factors, and circuit load balances should be compared to the design criteria.
3.5 Voltage Drops: Primary voltage drops calculated by computer programs should be corroborated with actual field measurements which have been adjusted to load levels equal to the computer runs. These field measurements can be obtained from periodic readings of the system's installed voltmeters or from voltage and current investigations performed on the system. Calculated readings that are different from the actual adjusted measured readings, need to be reconciled using good engineering judgment to justify new construction items. Costly construction projects should not be based solely on computer calculations that may be prone to input errors or based on assumptions not pertinent to the line being analyzed.
3.6 Recommendations: The CWP should include recommendations for correcting each item found that does not comply with the design criteria. This includes all problems found during the substation and circuit loading analyses, problems found in the engineer's review of the system's planning and O & M studies, and operating reports, and problems found in studying the power supply system if applicable to the borrower.
3.7 Alternative Solutions: The engineer usually has several options available to resolve existing and anticipated problems. Most solutions require new construction or equipment replacement. The engineer is expected to investigate all feasible alternative solutions and make recommendations that are in compliance with the LRP. Solutions recommended are also expected to be the most economical, considering both the distribution and the power supply system needs together as one system. The present worth cost of alternative plans can easily be determined and compared by downloading and using the computerized workbook attached to RUS Bulletin 1724D-104, "An Engineering Economics Computer Workbook Procedure."
3.8 Power Supply and Delivery Points: New power supply and delivery point construction items and projects, which are to be provided by a utility other than the borrower, need to be discussed with and concurred by the power supplier before the recommendation is included in the CWP. Agreement, in writing, needs to be reached on the location and amount of new capacity or delivery and the in-service date.4. THE CONSTRUCTION WORK PLAN REPORT
The purpose of the CWP report, which is a documentation of the CWP study and recommendations, is to describe, justify, and summarize the items which have been determined necessary for construction during the work plan period. Written justification usually explains the need for a system improvement to meet the design criteria pertaining to voltage, thermal loading, service reliability, or losses, and also explains economic benefits compared to other feasible alternatives. The contents of the report should contain sufficient facts and details, including maps, graphs, and tables, to accomplish the above purposes. Narratives should be concise, factual, and relevant. It is suggested that any information or data which does not contribute to the stated purpose of the report be omitted. A table of contents for a typical CWP is illustrated in Exhibit A. RUS recommends that all of the components listed in Exhibit A, plus all other pertinent subjects, be incorporated in CWPs submitted to RUS for approval.
4.1 Executive Summary: An "Executive Summary" section should be included at the beginning of the CWP report. This summary should be short enough to be read within a few minutes and fully understood without referring to other sections of the report. The purpose of the summary is to briefly describe the system, the basis of the engineering study, and summarize the proposed construction program. This summary should also include expected results and the estimated costs. The following items should also be included in the Executive Summary.
4.2 Historical and Projected Data: A section of the CWP report should document historical and projected system data, the design criteria, unit cost estimates and their derivation, and a written analysis of the various system studies and data that the engineer reviewed, prepared and used in performing the systems analysis. In general, this information is used to determine the portions of the system and equipment which do not meet the design criteria. The information is also used to formulate a basis for the acceptability and cost estimates of alternative plans to resolve the existing and anticipated problems.
4.3 Documentation: Another complete section of the CWP report should be used to document the entire construction program proposed. It is suggested that the items in this section be arranged in the same order as found on RUS Form 740C. All significant proposed new construction items, groups of items, and system modifications should be adequately and concisely described and justified. Justification usually includes the reason for and expected results of the construction, and also shows favorable economics when compared to other feasible alternatives.
4.3.1 Transmission line, substation, and other power supply items can be explained using form and contents similar to distribution items.
4.3.2 A concise written summary analysis of other relevant independent system studies, such as O & M, sectionalizing, Supervisory Control Data Acquisition (SCADA), load management, Automatic Meter Reading (AMR) feasibility, and system aging studies should be included in the report. This analysis should explain the study, its results, and the need for new construction. A copy of each study need not be included in or appended to the CWP report. A listing or table of the construction items and their associated costs proposed as a result of each of the above studies should be placed in the CWP report with the other required construction items.
4.4 Calculations:Samples of calculations performed by the engineer, and sample printouts of the computer programs used by the engineer, such as engineering economic analysis and distribution circuit analysis, should be included in the Appendix of the CWP report. It is desirable to include only one or two typical samples of calculations or printouts. However, the engineer should retain all pertinent calculations, data, and notes for future references.
4.5 The Appendix: of the CWP should also include maps of the system which show, as a minimum, the following information:
4.5.1 The first map should show the existing system, with anticipated loads (existing customer growth and additions), anticipated and planned circuit changes, and projected resulting primary voltages at the end of the planning period. The purpose of this map is to clearly describe the system and show anticipated problems at the end of the planning period without proposed new construction items.
4.5.2 The second map should basically contain all of the information included on the first map plus the proposed construction items and the resulting voltage and other system improvements. The purpose of this map is to show that the proposed new construction and changes will improve primary voltages or otherwise are beneficial to the system.
4.5.3 The above-mentioned maps should be drawn neatly, as close to scale as possible, and utilize accepted standard symbols. A key of the symbols should be included on the maps.5. ENVIRONMENTAL REPORTS
As part of the CWP, a review of the projects set forth in the CWP report will have to be made to determine if a Environmental Report (ER) or other environmental assessment is required. RUS has to make the final environmental determination. Refer to Title 7 of the Code of Federal Regulations, Part 1794, Environmental Policies and Procedures, for all of the requirements regarding environmental reviews.6. CONSTRUCTION WORK PLAN AMENDMENTS
A CWP amendment will be required for most needed changes to a CWP that has been approved by RUS. An example of a needed change to existing CWPs is a new project not included in the current CWP. Review of CWP amendment projects will also have to be made to determine if an ER or other environmental assessment is required.
7. APPROVAL OF CONSTRUCTION WORK PLANS
7.1 Approval: Where practical, a draft of the CWP report should be presented to the RUS GFR prior to completing the final version. The final version of the CWP should be presented to the system's board of directors for questions and answers and any modifications as may be deemed necessary by the board. The board of directors should then approve the CWP by resolution.
7.2 Approved Authority: RUS CWP approval authority is delegated to the GFR for all distribution, headquarters, and subtransmission facilities. Approval for any bulk transmission, generation, or other types of facilities contained in the CWP is delegated to the appropriate RUS regional offices in Washington, D.C. Two copies of the CWP report should be furnished to the GFR who will forward one copy to the Regional office in Washington, D.C. RUS approval of the CWP constitutes general approval of the need for the construction of facilities in the CWP. Borrowers seeking financing from RUS for the construction of these projects should consult the appropriate regulation regarding the need for design approval, contract approval, or environmental approval.
TABLE OF CONTENTS
(TYPICAL CONSTRUCTION WORK PLAN)
- Current Long-Range Plan
- Current O & M Survey (RUS Form 300)
- Sectionalizing Studies
- Annual Energy, Load, and Consumer Data
- Substation Load Data
- Transformer and Circuit Loads
- Load Current Measurements
- Voltage Measurements
- System Outages and Reliability
- Economic Analysis of Alternative Plans
- Distribution Circuit Analysis Printout
- Economical Conductor Sizes
- Map of Projected System Without Changes
- Map with Proposed New Construction Items
[NOTE: THIS LIST OF REQUIRED CONSTRUCTION ITEMS MAY NOT BE COMPLETE FOR ALL SYSTEMS. OTHER CATEGORIES, SUCH AS TRANSMISSION LINES, SCADA FACILITIES, AND HEADQUARTERS FACILITIES SHOULD BE INCLUDED IN EACH CWP AS APPROPRIATE.]
RUS CONSTRUCTION CODES
(For coding construction projects and for use on RUS Form 740c)
CODE NUMBERS EXPLANATION (DISTRIBUTION) 100 – 199 NEW LINES (New primary, secondary and service lines [not tie lines] where no lines presently exist. A conversion or line change required to provide new service should be included under Code 300. However, an exception would be one in which new line and conversion or line changes are required on the same work order project. In that case, the total costs are included under the code for the predominant cost activity.) 200 – 299 TIE LINES (New construction between two or more existing lines or substations) 300 – 399 CONVERSIONS or LINE CHANGES (Any conversion or line change of an existing primary circuit. Increased capacity of service [secondary and service] wires is to be included under Code 600.) 400 – 499 NEW SUBSTATIONS, SWITCHING STATIONS and METERING POINTS 500 – 599 SUBSTATION, SWITCHING STATION and METERING POINT CHANGES 600 – 699 MISCELLANEOUS DISTRIBUTION EQUIPMENT 700 – 799 OTHER DISTRIBUTION ITEMS (TRANSMISSION) 800 – 899 NEW LINES 900 – 999 NEW SUBSTATIONS, NEW SWITCHING STATIONS 1000 – 1099 LINE and STATION CHANGES 1100 – 1199 OTHER TRANSMISSION ITEMS 1200 – 1299 GENERATION 1300 – 1399 HEADQUARTERS FACILITIES 1400 – 1499 ACQUISITIONS 1500 – 1599 ALL OTHER