TAMS-Adjusted Corps of Engineers Alternative TAMS-Adjusted Western Railroad Association (WRA) I INTRODUCTION Numerous alternatives have been considered for replacing or rehabilitating Locks and Dam 26. There are almost as many costs, cost revisions, comments, comment rebuttals, and other information dealing with the engineering aspects of the problem as one might ever wish to find. However, nowhere can one find a concise summary that gives the major cost components of three of the most discussed alternates--the Corps rehabilitation alternate, the Western Railroad Association (WRA) plan, and the Illinois DOT plan. Also missing is an objective appraisal of what each really provides, and the risks and uncertainties associated with them. Nor can one find a comparison of plans having the same endresult from a functional aspect; i.e., a comparison of plans all having the same lockage capacity. The purpose of this document is to show clearly what, in our professional opinion, each plan will and will not provide, and the risks and uncertainties of each. This report also presents cost comparisons based upon providing the same lockage capacity. An Important Comment About The TAMS Report Tippetts-Abbett-McCarthy-Stratton (TAMS) recently evaluated certain rehabilitation alternates for the United States General Accounting Office, including one of the Corps' rehabilitation alternates, the WRA plan, and the Illinois DOT proposal1. The TAMS study and report 1. Evaluation of Proposals for Rehabilitation of Locks and Dam 26, were made because of widely varying estimates and opinions on rehabilitation alternates. Certain adjustments were made in the plans, and the cost estimates are marked in their report "as adjusted by TAMS." The report discusses the technical feasibility of the plans in general terms, and presumes the validity of certain vitally important assumptions made by the agency originally proposing them. These assumptions are properly noted as requiring confirmation, but we believe this cannot always be done. TAMS did not evaluate the adequacy and the soundness of the WRA and Illinois DOT plans, except in certain specified areas-usually deficiencies. The adjusted TAMS estimates, therefore, should be viewed as being only as good as the soundness of the plans on which they are based. The bases themselves were not evaluated for the schemes as a whole. For example, the WRA proposes to provide additional lateral restraint for the dam by using a system of piles and post-tensioned anchors installed in the dam piers without building cofferdams. TAMS states the proposal is conceptually feasible and submits a revised cost which assumes this can be done. TAMS thus gives credibility to a scheme which is certainly questionable regarding its constructability, and which we believe is improper in any event. II SUMMARY EVALUATION OF THE REHABILITATION report. Table I is a summary of the estimated costs given in the TAMS The costs, as adjusted by TAMS, are the focus of this discussion. Only by analyzing the original costs plus the additions and subtractions made by TAMS can one see what each of these adjusted estimates really provides. We analyzed each scheme and the results are presented in the following pages. Each analysis includes a general description of the rehabilitation scheme; the cost of major construction elements; and an evaluation of the problems, risks, and uncertainties of each. A. TAMS-ADJUSTED CORPS OF ENGINEERS ALTERNATIVE 1. General Description This plan was not recommended by the Corps, but is one of many alternatives the Corps considered and rejected. The plan calls for a temporary lock on the Missouri bank and for completely rehabilitating |