Environmental Capacity of Local Streets with Street Treatments
Degree GrantorUniversity of Canterbury
Degree NameMaster of Engineering in Transportation
“I want my street to be like an extension to my driveway, where the kids can play safely and where the traffic does not bother us,” said one resident. Another said that she “likes traffic... We live in a city.” This gives an idea of the broad range of opinions and views that exist on traffic. Traffic in local streets in a concern for residential amenity. There is always conflict between the residential amenity and traffic access functions of local streets. There is much debate on what a true local road is. The concept of environmental capacity was developed to identify a suitable maximum traffic volume on local streets, without overly adversely affecting residents. It was first introduced by Buchanan and Appleyard in separate research in the 1960s. Both men settled on thresholds of 2,000-3,000 vehicles per day. Chesterman, in 2009, carried out a study in Christchurch, surveying residents on four local streets with varying traffic volumes. He found residents living on busier streets felt that their streets were busier, noisier and less safe. There was also an increasing trend for these residents to have their houses turned away from the street and they tended to have less personal involvement with their neighbours. He found that perhaps a more suitable environmental capacity estimate was between 1,500 and 2,000 vehicles per day. This study looked at further Christchurch streets, this time with street treatments, such as street calming and tree plantings, aiming to find an environmental capacity for these streets as well as seeing whether the street treatments affected the perceived environmental capacity. As well as reinforcing most of the conclusions found by Chesterman, a higher environmental capacity of around 2,000 vehicles per day was found for the surveyed streets. This suggests that indeed, street treatments such as those used in the surveyed streets can increase the environmental capacity, which has implications for local councils who want to maintain road traffic carrying capabilities without having unsatisfied residents.