Effects on the environment are rarely valued in planning infrastructure for different modes of transport. This can detract from optimal planning and fair competition, which might be better served by valuing environmental quality changes through actual travel time savings. New transport infrastructure often creates both positive and negative effects for the same groups of users, although to different degrees for different individuals. This paper illustrates a proposed methodology to investigate the effect of a planned transport infrastructure investment through a survey of potential users of the Haningeleden road project in Stockholm. Postal questionnaires were sent to a random sample of 2400 persons living in the affected area in May and June 2013, including detailed questions about their travel patterns and visiting frequencies, and whether, after reading a description of the proposed change, they would be in favour of the proposed change. The negative encroachment costs and the positive relief from traffic in other areas were estimated in travel time savings.