Harrison

This is an appeal from a judgment enjoining the County of San Mateo from the collection of special assessments levied against certain property owners (plaintiffs) within the East Palo Alto-Belle Haven Storm Drain Assessment District, designated as Units I and II, and ordering a refund of assessments already collected.

The storm sewer special assessment was levied by the San Mateo Board of Supervisors (defendants) under the provisions of the Municipal Improvement Act of 1913, as amended (Sts. & Hy. Code, § 10000 et seq.) The amount of the assessment was calculated upon a rainfall runoff coefficient based wholly upon the zoning of the units in question. Two suits were consolidated, that of plaintiff Southern Pacific Transportation Company and a class action brought in behalf of property owners who had filed timely written protests to their individual assessments.

The trial court declared void those assessments on the real property of members of the class on the ground that there was no substantial evidence that the property would obtain a special benefit from the proposed improvements. He further ruled that an invalid method of spreading the assessment was used and that…