THE AFFECTED ENVIRONMENT DRAFT NATIONAL MALL PLAN / ENVIRONMENTAL IMPACT STATEMENT THE NATIONAL MALL THE MALL CONTENTS: THE AFFECTED ENVIRONMENT THE AFFECTED ENVIRONMENT .................................................................................................... 249 Context for Planning and Development of the National Mall ...................................................................251 1790–1850..................................................................................................................................................251 L’Enfant Plan....................................................................................................................................251 Changes on the National Mall .......................................................................................................252 1850–1900..................................................................................................................................................253 The Downing Plan...........................................................................................................................253 Changes on the National Mall .......................................................................................................253 1900–1950..................................................................................................................................................254 The McMillan Plan..........................................................................................................................254 Changes on the National Mall .......................................................................................................256 Federal Legislation and Administration.......................................................................................256 1950 to 2000 ..............................................................................................................................................256 Federal Plans ....................................................................................................................................256 Changes on the National Mall .......................................................................................................257 Federal Legislation ..........................................................................................................................258 Current Conditions — 2000 to 2008......................................................................................................258 Federal Plans ....................................................................................................................................258 Changes on the National Mall .......................................................................................................259 Federal Legislation ..........................................................................................................................259 Cultural Resources ...........................................................................................................................................260 Memorials .................................................................................................................................................260 Historic Districts ......................................................................................................................................260 The Mall............................................................................................................................................260 East and West Potomac Parks........................................................................................................266 Federal Triangle Historic District .................................................................................................266 Northwest Rectangle.......................................................................................................................266 Pennsylvania Avenue Historic District.........................................................................................266 Downtown Historic District ..........................................................................................................266 Historic Properties and Cultural Landscapes ......................................................................................267 The National Mall ...........................................................................................................................267 The Mall............................................................................................................................................270 Washington Monument and Grounds .........................................................................................277 West Potomac Park (North of Independence Avenue) .............................................................281 West Potomac Park (South of Independence Avenue) ..............................................................288 Other Features Contributing to National Register Listings ...............................................................293 Roadways..........................................................................................................................................293 Natural Resources ............................................................................................................................................294 Water Resources.......................................................................................................................................294 Surface Water...................................................................................................................................294 Floodplains and Stormwaters ........................................................................................................296 Groundwater....................................................................................................................................297 Soils 297 Fill 297 Soil Conditions.................................................................................................................................298 Vegetation .................................................................................................................................................298 Elm Trees..........................................................................................................................................299 Cherry Trees.....................................................................................................................................299 i CONTENTS Turfgrass ...........................................................................................................................................300 Fish and Wildlife ......................................................................................................................................301 Demonstrations, Special Events, and National Celebrations .....................................................................303 Background Information ........................................................................................................................303 The Importance of the Venue........................................................................................................303 Regulations .......................................................................................................................................303 Number and Size of Events ............................................................................................................303 Time Frame ......................................................................................................................................304 First Amendment Activities ....................................................................................................................304 National Celebrations..............................................................................................................................305 Special Events ...........................................................................................................................................305 Access and Circulation.....................................................................................................................................309 Public Access.............................................................................................................................................309 Road Network..................................................................................................................................309 Visitor Access ...................................................................................................................................311 The Pedestrian Environment..................................................................................................................315 Bicycling ....................................................................................................................................................316 Visitor Experience ............................................................................................................................................317 Visitor Use Characteristics......................................................................................................................317