 During 1875 and 1876 he was engaged as consulting engineer in various works in conjunction with Mr. Charles Pfeiffer, who had been associated with him on the St. Louis bridge, Mr. Thomas J. Whitman, chief engineer of the Waterworks, and Prof. Charles A. Smith of Washington University.Amongst other engagements he was engineer for the commissioners who purchased and laid out Forest Park.In the autumn of 1876 the new charter of the city of St. Louis, by virtue of which the city was separated from the county of St Louis and made, as to its local affairs, to a large degree independent of the State Legislature, was inaugurated, and Colonel Flad was elected the first President of the newly constituted Board of Public Improvements.