he Councilmember shall send a letter to the Department of Transportation identifying the street segments to be included in the restricted area, the reasons for the request, and verifying receipt of petitions showing support for the restriction by a substantial number of affected community residents. Upon receiving a written request from a Councilmember pursuant to this subdivision, the Department of Transportation shall conduct an investigation to determine whether or not the parking of oversize vehicles between 2:00 a.m. and 6:00 a.m. on the designated street segments is adversely impacting the visibility of oncoming traffic, creating constrictions in the traveled way, or substantially reducing the availability of parking for residents and businesses. In making its determination, the Department shall consider all relevant factors, including without limitation, the location of driveways relative to parked oversize vehicles, the width of oversize vehicles when compared to other parked vehicles, the existing availability of parking, the impact the oversize vehicles are having on parking availability for residents and businesses, the effectiveness of restricting oversize vehicle parking in alleviating any adverse impact on the visibility of oncoming traffic, constrictions of the traveled way and reduced parking supply, and whether signs may be erected on the street segments in a manner that provides adequate notice of the restriction. The Department of Transportation shall report the results of its investigation and determination to the City Council. The City Council may, by resolution authorize the street segments upon which the parking of oversize vehicles shall be restricted between 2:00 a.m. and 6:00 a.m., except for those oversize vehicles displaying a valid permit issued pursuant to the provisions of Subsection (c) of this section. Upon Council action designating street segments with oversize vehicle parking restrictions, the Department of Transportation shall cause appropriate signs to be erected in those street segments, indicating the parking limitation prominently on the sign and stating that motor vehicles with valid permits shall be exempt from the restrictions.