The board of supervisors shall set apart and turn over to the commission out of the general fund of the county 25 per cent of the cost of acquiring the rights of way for, and construction of, the boulevard and 25 per cent of the cost of maintaining and repairing the boulevard. All money so set apart and turned over to the commission shall be used exclusively for the purposes for which it was so set apart and turned over.
The board of supervisors shall set apart and use for road work in the district all moneys raised in the district by the county for road purposes.