(a) The several county courts through whose counties run any watercourse, lake, bay, or swamp which may be too burdensome to bridge and keep in repair by the inhabitants thereof are fully empowered to grant privileges to persons to build toll bridges over or turnpikes or causeways along them, or through any overflowed or wetland, whenever the interest of the county or the traveling public shall in their discretion demand the improvement.
(b) No privilege or franchise for the construction of a toll bridge over any navigable stream shall be effective until consent is obtained by the federal government for the construction of the bridge.