Section 2W. There shall be established and set up on the books of the commonwealth a separate fund to be known as the Water Pollution Abatement and Drinking Water Projects Administration Fund. There shall be credited to said fund any amounts transferred under sections 5 and 18 of chapter 29C and any income derived from the investment of amounts credited to said fund. Amounts credited to said fund shall be held in an expendable trust and the department of environmental protection shall report monthly all amounts credited to said fund and all expenditures by subsidiary on the Massachusetts management and accounting reporting system, so-called. Said amounts shall be used solely for the administration of section 27A of chapter 21 and section 18 of said chapter 29C.