Ed. Code, § 17570

Any provision to the contrary notwithstanding, the governing board of any school district, other than a city school district with over 50,000 pupils in average daily attendance during the preceding fiscal year, may construct pedestrian walks, footbridges, and pedestrian tunnels when required for the safety of pupils attending the schools of the district, may acquire easements and rights-of-way for those purposes, and may appropriate money to acquire such easements and rights-of-way and to pay the cost and expense of the improvements, whether made by the board under contract executed by the board, or under contracts made in pursuance of any of the general laws of the state respecting street improvements, or under other contracts made in pursuance of the charter of any county or municipality. Pedestrian walks, footbridges, and pedestrian tunnels shall be constructed, and such easements or rights-of-way for those purposes shall be acquired, within one mile of the school for the pupils of which the walks, bridges, and tunnels are necessary.