As s note, homeowners can hose down a driveway with a garden hose to expedite the hardening process.  On occasion soapsuds may appear when hosing down the asphalt.  This is simply due to the fact that chlorine in city water combines with the diesel fuel in asphalt to form soapsuds. When driving on asphalt that is not fully cured it is recommended to drive cautiously.  This is due to the fact that driving too fast can cause asphalt to become scarred.