SPRITZBRUNNEN, BASEL, SWITZERLAND
The “Spritzbrunnen” at the Dreirosenanlage in Basel was created between 2004 and 2006 and designed by the Ernst and Hausherr Landscape Architechts, Zürich. The project was initiated by the Building Department of the Canton of Basel-Stadt. The City Gardening and Civil Engineering Office of the City of Basel was in charge of its realization. The project received the 2006 Recognition Award of the “Living City” Foundation.
The audio in the video switches between the fountain being in and out of operation (“Spritzbrunnen in Betrieb” / “Spitzbrunnen außer Betrieb”).
The "Spritzbrunnen" fountain consists of seven water jets with nozzles that are placed at different heights. The jets emit a broadband water noise as they hit the water surface in the basin with components starting at 200 Hz, but also relatively strong low frequencies. This results in a sound which is perceived as very diverse. The background level without the fountain is 55 dB(A) when there is little or no traffic. With the water noise of the fountain, 59 dB(A) is measured. The total sound level increases to 64 dB(A) or more when a tram passes. 
The "Spritzbrunnen" at the Dreirosenanlage in Basel is located between the recreational zone and the road crossing. This soultion is preferable, because, in contrast to the more aesthetically appealing solution of placing a beautiful fountain in the middle of a recreational zone, it more efficiently masks the road traffic noise. 
Since the noise of the water fountain covers a more narrow angle than the traffic noise, the masking effect is successful for traffic on the intersection, but not for the access roads from the left and right. Vertically, however, the direction of incidence of the water noise coincides with the direction of the traffic noise. This is easier to achieve than horizontal masking. The overal acoustic effect of the fountain is that quieter traffic noise is drowned out and that louder events no longer stand out so strongly. Thereby, the dynamics of the traffic noise are reduced, making it less prominent. 
Entry submitted by: Beat Hohmann, Regina Bucher, Office for Environment and Energy, Canton of Basel-Stadt.
Photo: Regina Bucher.
Audio, video: Beat Hohmann.