Fla. Stat. § 171.21
A joint planning agreement, a charter provision adopted under s. 171.044(4), or any other interlocal agreement between local governments including a county, municipality, or independent special district is not affected by this part; however, a county, municipality or independent special district may avail itself of this part, which may result in the repeal or modification of a joint planning agreement or other interlocal agreement. A local government within a county that has adopted a charter provision pursuant to s. 171.044(4) may avail itself of the provisions of this part which authorize an interlocal service boundary agreement if such interlocal agreement is consistent with the charter of that county, as the charter was approved, revised, or amended pursuant to s. 125.64.
Fla. Stat. § 171.21