Q. Why do we have speed humps? 
A. Speeding on residential streets is a common complaint of concerned citizens. Although enforcement of speed limits by police departments is an effective means of reducing speeds, limited resources do not allow such enforcement on a regular and permanent basis. Research has shown that speed humps are an effective approach to slowing down traffic on residential streets. 

Q. What is a speed hump and how is it different from a speed bump? 
A. A speed hump is a gradual rise and fall of the pavement surface along the roadway extending across the pavement width. Generally, speed humps used on residential streets are *2 to *2 feet long with a maximum height of 3 to 4 inches. Speed "humps" are different from speed "bumps", which are seen in many private parking lots. A speed bump is abrupt, having a height of 3 to 4 inches over a length of 1 to 3 feet. Speed bumps cause most vehicles to slow down to almost a stop to go over it. Speed humps, on the other hand, are designed so most vehicles can go over them at *0 mph without causing driver discomfort. 

Q. How are speed humps effective in controlling speeds? 
A. Speed humps cause a gentle vehicle rocking motion that causes driver discomfort, thus resulting in most vehicles slowing down to *0 mph at each hump. Depending upon street geometry, speed humps are placed every **0 to **0 feet. The presence of speed humps causes drivers to slow down at the humps and in between properly spaced successive humps. Speed humps have the advantage of being self-enforcing. They are sometimes referred to as "sleeping police officers". 

Q. What will happen if I go over speed humps at high speeds? 
A. At high speeds a speed hump can cause significant driver discomfort. At such speeds it can act as a bump and jolt the vehicle's suspension and its occupants or cargo. 

Q. Do speed humps reduce cut-through traffic? 
A. The primary purpose of speed humps is to reduce the speeds of vehicles traveling along a roadway. Traffic diversion due to speed humps is a side effect which may or may not result. A possible disadvantage of speed humps is that motorists may avoid the speed humps by using other nearby streets in the area. 

Q. How is a driver warned of the presence of speed humps? 
A. On any street with speed humps, warning signs such as "Road Humps Ahead" are placed before the beginning of each series of humps. These signs also indicate the speed at which drivers are advised to travel over the hump. To be properly visible, the speed hump is marked with diagonal white stripes. 

Q. Can speed humps be placed on any street? 
A. Speed humps are placed only on residential streets with not more than two lanes and with a speed limit of *0 mph or less. For safety reasons, speed humps are not installed within sections which are curved or where the street slopes uphill/downhill. Speed humps are not typically installed on streets where emergency facilities are located. The Department of Public Works and Transportation communicates with the Austin Fire Department and Emergency Medical Services to ensure that the speed humps will not greatly impact their services. Increases in response time of approximately ***0 seconds per hump may exist with the installation of speed humps. 

Q. What are the different types of speed humps? 
A. There are two different speed hump designs used by the City of Austin: 1. The circular speed hump, which is *2 feet long, and used on those residential streets which provide access to multiple streets in the neighborhood. 2. The flat-topped speed hump, which is *2 feet long, used on local streets within the neighborhood. 

Q. How can I get speed humps on my street? 
A. Neighborhood Traffic Calming Program