Agenda Packets - 1995/02/06 - Laserfiche WebLink

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) The costs and values are necessarily tied to volume rather than area. In Pasqual and Riera's value ;on, there is an implicit assumption that the price is based on usable thicknesses of •and space that are related to the value of the land at a particular depth. Thus the value of underground "land" changes with the changes in construction cost and the price a tenant or is willing to pay for the space obtained at a particular depth from the surface, i.e. the area pmen and land together with its associated thickness. To avoid confusion, it appears better end is � ��the �� treat- underground space as a value per unit volume. This is in fact what Pasqual and Riera did iy applied their approach to a case example. • '33 Case Example for the Evaluation of a Utilidor , ' era used their-approach to underground land-valuation to investigate the-alternatives of- a common utility tunnel versus the traditional approach of separate utility locations beneath the . Midway for construction of a major ring road project in Barcelona. The value for underground land was determined from the known value of an underground parking space in Barcelona (p = US$25000), the known cost of constructing an underground parking space (c = US$12,000) and an assumed value of the developer's margin (b = 0.35). From equation (1), the value of the underground land is US$6519 per m2 (US$606 per ft2). This can then be converted to a value per m3 of underground space by multiplying by the volume of underground space necessary to provide one packing space (including a proportional part of the parking access space, etc.). This volume was estimated to be 57.5 m2 and hence the value of underground space was calculated to be iiP USS113 per m3 (US$3.20 per ft3). re Applying the estimated value of underground space to the ring road utility comparison, yielded a comparison that, since the common utility tunnel would save 7.39 m3 per linear meter of roadway, the land value savings per meter of roadway would be US$840. Over the 25,735 m of system being considered, the total land value savings were calculated to be US$21.5 million. e The four main variables in the overall comparison were • Construction costs - greater for the tunnel option • Maintenance costs - considered for the tunnel option only • Future utility repair costs - less for the tunnel option • Underground land costs - less for the tunnel option The underground land value was the most significant factor in the comparison with savings in repair costs being the next most significant. The discount rate assumed and the period over which the savings in underground land are to be taken were important factors in the calculated magnitude of the savings. There are many other issues which bear on the general use of common utility tunnels. These issues include (APWA, 1971 and Duffaut and Labbé, 1992): 17