"As many cities have done, Sparks turned to planned developments because its zoning code was stuck in cement. Title 20, the city's Zoning and Land Use Controls, was adopted in 1976 and amended only slightly after that, partly because of budget constraints.
Then came the population boom. Traditional zoning wasn't doing enough to guide it and a more flexible tool was needed.
In 1991, Sparks adopted a master plan that included a plan for the northern Sparks sphere of influence. Under Nevada law, cities must declare a sphere of influence consistent with the regional plan; it is best defined as a potential development area extending into surrounding unincorporated land.
The sphere-of-influence plan requires the use of planned development standards handbooks, which allow the city to review each project's infrastructure and design. In northern Sparks, those handbooks replace the city's zoning and land-use controls for that planned development area."