Highway franchising and real estate values

It has become increasingly common worldwide to auction the construction and operation of new highways to the bidder that charges the lowest toll. The resulting highway franchises often entail large increases in the value of adjoining land developments. We build a model to assess the welfare implications of allowing large developers to participate in these auctions. Developers bid more aggressively than independent construction companies because lower tolls increase the value of their land holdings. Therefore developer participation unambiguously increases welfare, yet this increase is not necessarily monotonic in the number of developers participating. Welfare also increases when large developers can bid jointly.