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At the request of the Techn1cal Collllll1ttee, Mn/DOT prepared a volume to capacity analyalll of the reaults of the travel demand project101ls from Table 6. The results are ahown in Tables 7 and 8. Table ij has already presented the key assumptions used to evaluate the capacity of each river crossing. Note that in this analysiS only I-69ij has a capacity determined by the bridge itself. The other routes are l1mited by conditions off the bridges. This finding can be particularly important when considering short term actions. Table 7 presents a set of index numbers derived by dividing est1mated peak hour demand by the capacity of the route at its crit1cal locat1on. Peak hour demand is as mentioned in Table ij, which assumes that 10 percent of daily traffic is in the peak hour. Also, directional IIpl1t 18 60 percent in the busiest direction for anyone bridge alternate except 'JIl 101, which is 65 percent, and I-69ij, which is 55 percent. It is important to remember that changing the..e a....UIIlptlon.. can change the ratios. Generally speaking, 1f the ratio is greater than 1.0, it is expected that congestion on the route in question 11111 be unacceptable to the traveling publ1c. Values of 0.9 or less are preferred. Based on that criteria the values on Table 7 are cause for concern. It is not recoDlDended that these ratios be directly used to evaluate the relative overloading of the river crossings. For that reason an alternate "normalized" analysis is included. From Table 7 it appears that demand on TH 610 would exceed capacity by 30 to ijO percent, the .3 to .ij portion of the value identified in the V/C ratio of 1.3 or 1.ij. In point of fact the assWDed TH 610 demand (38ijO vph from Table Ii) can be handled by a four-lane bridge of the design now being built. The capacity deficiency 18 not on the bridge itself but, as noted in Table Ii, occurs at the west terminus with 'JIl 252. AllsWD1ng this to be correct 1I1th TH 610 at capacity in the "no build" assumption, i.e. with a V/C ratio of 1.0, the rest of the data on Table 7 is "normalized" to this .assumption. The results are shoWll in Table 8. Table 8 demonstrates that the worse relative congestion for all alternatives would still be on TH 169 (Ferry Street). Any new crossing would have excess capacity in year 2000, but all regional routes would be fully used (V/C is 1.0 or greater). TH 169, however, shows a V/C greater than 1.1 for all tested alternatives, even when normalized. - The analysis of probable future demand is only one input to the findings on both problems and solutions. An environmental criteria checklist was used by the Technical CoIlllll1 ttee to help clarifY other important factors in selecting study recommendations. 20 37