**Sub-problem 1c: Analysis of
Future
Conditions**

*Step 2. **Results*

For the analysis of future conditions, it is often appropriate to
select a peak hour factor of 1.0, considering that the projected future
volumes, as well as other critical analysis parameters, have a relatively
high degree of uncertainty associated with them. In this context, then,
using a peak hour factor of 1.0 is equivalent to evaluating the intersection
on the basis of the estimated average conditions for the hour rather than
the peak 15 minutes. In many cases, the accuracy resulting from this
approach is on par with the cumulative accuracy that one can expect for the
other critical analysis parameters that must also be estimated.

The value of the arrival type for the signalized
intersection option depends on whether the signal will be interconnected
with the adjacent intersections and the quality of progression that will be
achieved. It is usually conservative to assume random arrivals (Arrival Type
3). The values of the saturation flow rate, the critical gap, and the follow
up time depend on local conditions and whether, as volumes increase, driver
behavior may change over time. We will assume for this analysis that they
remain the same as the original analysis. These are all reasonable
assumptions, but most likely the assumptions are less accurate than the
estimates we were able to prepare for the existing conditions analysis.

*What other factors should be considered? *In
addition to the factors discussed above, we must also have forecasts of
future volume levels. In order that they might be as accurate as
possible, future volume projections should not just consider historic
patterns of growth but also current local policies regarding development. For example, if growth management policies are in effect, future growth may
be lower than historical patterns. And, since we can't know precisely the
composition of the traffic stream with respect to vehicle types, it is again
usually conservative to assume a passenger car equivalence of 1.1.

For this case study, we are unaware of any land use
policies that might change historic growth trends. Since we know that traffic volumes on U.S. 95 are
increasing at the rate of 2 percent per year, it is conservative to assume
that this rate will continue and that, with compounding, the volumes in ten
years will be about 22 percent higher than today's volumes. Click here to see the future traffic
volumes.

Let's continue to see the results of the computation.