Mechanical and Electrical Design of Pumping Stations - 03...

Chapter - 03 : Design Memorandum Requirements...

3-1. General...

The design memoranda are prepared in the preconstruction engineering and design (PED) phase of a project. This phase begins the most intensive engineering effort and culminates with the preparation of contract plans and specifications. The design engineer should also be involved in the reconnaissance and feasibility phases of the project. The applicable portions of ER 1110-2-1150 will govern the contents and formatting of the various required submittals. The submittals required for a particular project will be discussed at the earliest design coordination meeting, and the listing of design memoranda required will be established either at this meeting or as early as possible after this meeting. The following describes design documents developed during the design phase of a project. Other design documents, such as letter reports, can be substituted but should still contain the information and data required below.

3-2. Design Memoranda and Documents...

For each project, there are different combinations of design memoranda prepared before proceeding to plans and specifications. These include General Design Memorandum, Feature Design Memorandum, Letter Reports, and Design Documents. Station layout and equipment selection should be investigated in sufficient detail, in the early design memorandum stage, to permit citing of the station and preparation of a cost estimate. Hydrology and hydraulic studies should present the required pumping conditions used for selection of the pumps. Information should include discussing the use of Government- furnished equipment if that method of pumping unit procurement is proposed. Detailed mechanical and electrical design data and computations should be included to allow approval of the final layout and design before preparation of plans and specifications. The results of alternative studies for the station layout and equipment selection should be presented. Design computations to determine size, strength, rating, adequacy, and interrelationships of mechanical, electrical, and structural items should be shown in sufficient detail to allow an engineering review. All formulas and assumptions used should be indicated. Copies of typical manufacturers’ performance data for the proposed equipment and correspondence with manufacturers should be included. Any deviations from this manual must be indicated in the text portion of the memorandum. The memorandum should include an analysis of the schedules for the procurement of the pumping equipment and construction of the pumping station.