Utah Supreme Court
631 P.2d 899 (Utah 1981)
To be reasonable, municipal fees related to services like water and sewer must not require newly developed properties to bear more than their equitable share of the capital cost in relation to the benefits conferred.
To determine the equitable share of the capital cost to be born by newly developed properties, a local government should determine the relative burdens previously borne and yet to be borne by those properties in comparison with the other properties. The fee in question should not exceed the amount sufficient to equalize the relative burdens of newly developed and other properties
The Banberry decision suggested 7 factors to consider when determining if an impact fee is reasonable:
1. The cost of existing capital facilities;
2. The manner of financing existing facilities;
3. The relative extent to which newly developed properties and other properties have already contributed to the cost of existing facilities;
4. The relative extent to which newly developed properties contribute to the cost of the facilities in the future;
5. The extent to which newly developed properties are entitled to a credit because of construction of new public facilities;
6. Extraordinary costs to service newly developed properties;
7. The time-price differential.
These factors were adopted as part of Utah’s Impact Fees Act.