Seattle city engineer Reginald H. Thomson may have been the driving force behind the Denny Hill regrades, but they could not have occurred without public support. In order for a regrade to proceed, at least 50 percent of the people who lived in the affected areas had to sign a petition. For example, the Second Avenue regrade needed the signatures of 67 property owners. A completed petition triggered the next phase, which was a city council ordinance that defined the boundaries of the regrade. A second ordinance then provided the funding mechanism, or what was known as a Local Improvement District (LID).