South Florida-based developer Adler Group LLC wants to build its first project along the Miami River. Adler wants to build on about 4.7 acres, which include a site it owns at 230 SW Third St. and two adjacent sites, 444 and 460 SW Second Ave. It wants to either lease or buy from the city of Miami. Exactly what it would build remains unknown but preliminary plans show up to four towers, including apartments and a new city administration building to replace the existing one at 444 SW Second Ave. The proposal depends on voters approving a referendum for the land lease or sale. Adler wants the measure to be on the Nov. 6 ballot. (Renderings by Nichols Brosch Wurst Wolfe & Associates.)