All revenues and moneys derived from the operation of the combined waterworks and sewage system shall be held by the city clerk separate and apart from his private funds and from all other funds of the city. All of such sum, without any deductions whatever, shall be delivered to the city treasurer not more than 5 days after receipt of the same, or at more frequent intervals as may from time to time be directed by the city council.
('69 Code, § 20-8)