The supporters and opponents of Folsom’s slow-growth initiative agree that the city needs a second traffic bridge over the American River. But they cannot agree where the bridge should be built. And the two sides are far apart in their interpretation of what Measure N, to be on the ballot Aug. 22, says about a second bridge for Folsom. Proponents said the initiative requires the city to study the possibility of building the bridge just below Folsom Dam. A “yes” vote also will prohibit the building of a bridge over Oak Avenue Parkway or other areas leading into residential streets. Opponents say the measure is confusing. Some believe that it mandates a bridge below the dam while others say the language in the initiative is so unclear that lawyers will be working overtime to interpret it.