Mode of arrival to the Kennedy Library will be primarily by automobile, non-scheduled bus and public transportation. On an average year basis an estimated 65.4 per cent of visitors will arrive by automobile, 8.6 per cent by public transportation, 23.9 per cent by non-scheduled bus (charter bus, tour bus and school bus) and 2.1 per cent by other means, including walking, taxi, and bicycle. Those visitors arriving by automobile include those who are passengers and those who are in rental cars. These estimates were derived by segregating the market segments on a monthly basis and origin basis and applying a mode split to the various market segments; i.e., SMSA residents, including school children in groups, will have a modal split of 35.4 per cent automobile, 22.5 per cent non-scheduled bus and 6.5 per cent other mode. It is estimated that visitors to the SMSA will have an arrival pattern to the facility of 73 per cent by automobile, 10 per cent by public transportation, 15 per cent by non-scheduled bus and two per cent other mode. Applying figures of 94 per cent automobile, one per cent public transportation and five per cent non-scheduled bus (excluding school groups) to the other market sectors results in the overall yearly mode split.

Nearly four out of ten visitors are likely to arrive during the summer months when the impact of university population activity levels are at their lowest. Approximately one-third of the visitors are expected during the weekends when employment related traffic and other activities are greatly reduced. During a given day, a great many visitors are likely to avoid peak traffic, although nearly 65 per cent of the visitors will use their automobile as a mode of arrival. However, a trip to the Library being more of a family affair, "cars" on an average will carry 3.5 persons, an occupancy rate almost double the average all-purpose trip rate. All of these estimates are primarily applicable to the stable year visitation which is the only significant estimate with long-term effect.

In summary, it can be concluded that, on a May weekday from 4 to 5 p.m. (a time during which the area experiences its highest total existing traffic flow), even the highest projection of Library generated traffic will not have a measurable effect on the traffic operations of any individual roadway or the entire street network. On an August Saturday the increase in total traffic due to the Library is more pronounced, but since the combined traffic volumes on the entire network will still be lower than the existing volumes on a typical non-summer Saturday, minimal effect on intersection operations can be expected. On Sundays, although higher increments of Library generated traffic are predicted than on Saturdays, minimal effect is expected since Sunday base volumes are even lower than those on Saturdays.

Therefore, on the basis of the foregoing discussion and the conclusions found for the peak year, it is clear that the additional traffic due to the Library cannot be expected to have any measurable impacts on traffic operations in the area during the stable years. If the highest visitor projection for the stable year (1,030,000) were considered, there would still not be any noticeable effect since this would change the Library volume increments by only about 10 per cent and the total traffic by about 1 per cent. This falls well within the limits of sensitivity for the Library traffic projections which can be expected to vary by a factor of 20 per cent plus or minus.

Transportation Impact/Vehicular Traffic & Circulation

Although the Library visitors will generate, at most, minimal adverse traffic impacts, this document presents a local circulation improvement plan for the site vicinity. This plan provides for better circulation of the incremental as well as existing traffic. It provides for the removal of less than 25 metered parking spaces. The implementation of such a plan would require further detailed analysis by the City.

Finally, the traffic volumes generated by the Library will not superimpose peaks on the existing volumes but rather occur on non-peak periods. Furthermore, in an effort to meet the modified EPA air quality standards, the City will have to work with regional agencies to change the existing traffic patterns. The increase in traffic due to the Library visitors is not likely to hamper such an effort.

Projected Non-Library Parking Demand

An analysis of the Harvard Square parking situation, in general, indicates deficiencies in supply, location and kinds of parking available. Currently, there is an estimated need of 1,500 parking spaces in the Harvard Square area. At the time of maximum accumulation it is estimated that nearly 30 per cent of the vehicles are illegally parked. The underlying cause of illegal and overtime parking is apparent space shortage. The relatively high turnover of illegal spaces in Harvard Square indicates that most of the need is for shortterm spaces. Illegal parking on streets is not only disruptive of vehicular, bicycle and pedestrian flow but to many it is a source of visual blight.

The net incremental parking demand generated by the Library visitors will be entirely satisfied by the on-site and satellite parking facilities.

During the stable year parking demands for the visitors will be met by the on-site parking lot with the exception of less than 20 operating days. During the peak year satellite parking will be required for about 70 days. These totals may be further reduced by adjustments in the operating schedule of the Library.

The parking demand analysis is again based upon relatively high estimates of the expected visitors and therefore, on-site parking facilities may fulfill all the visitor related demands. Provision has been made, however, for satellite parking. It is noted that the City of Cambridge is planning to use a city dump site for a parking facility during the bicentennial period.

The existing parking shortages and additional parking requirements for the City of Cambridge is being currently examined by its Planning Department. Their current proposals such as one on Nutting Road for 500 parking spaces addresses their problem. This and other similar proposals were examined during the EIS process although such an analysis extends beyond the scope of this statement. The progress made by the City to date and their future implementation plan will contribute to a solution of the parking problem of the City as envisioned by the City officials.

Public Transit

The rapid transit stations at Harvard Square (Red Line) is the third busiest in the entire system. However, the number of boarders is below the capacity of the station. The operating hours and schedules of the fixed rail Red Line, are efficient enough to meet the present and future demands of Cambridge and its surrounding areas.