A recent SF Chronicle article demonstrates that sound walls don't solve freeway noise problems and can even worsen them: "I have not had a full night's sleep since that wall's gone up." said Grace Dean, referring to the sound wall on Fwy. 680 in Danville (Contra Costa County), recently constructed by Caltrans. "Nothing around here has degraded our living style as much as these walls" said Debbie Rowland, who lives north of San Rafael (Marin County). Sound waves reflect off of large objects, like sound walls. Furthermore, sound waves often curve downward after being reflected, depending on the atmospheric conditions.