San Diego County obtained an AA+ rating from Fitch Ratings on $30 million in certificates of participation, a type of bond, which will be issued next week. The debt will go toward financing of a 600-space parking structure a block from the County Administration Building.

The garage is part of a larger waterfront park project that broke ground last month and is estimated to cost $44 million.

In its recent report on the bonds, Fitch said the implied rating on the county’s general obligation debt was AAA, the highest the ratings service assigns. It also rated the county’s outstanding pension bonds and another certificates of participation issue at AA+, while stating the county’s outlook was stable.

Fitch cited the county’s large and diverse tax base, a slow but steady economy, its strong financial position, and low debt among the key rating drivers.