In order to insure safe drinking water in all public water supplies, the commissioner has the following powers:
(a) To approve the site, design, and construction and alteration of all public water supplies and, for community and nontransient noncommunity water systems as defined in Code of Federal Regulations, title 40, section 141.2, to approve documentation that demonstrates the technical, managerial, and financial capacity of those systems to comply with rules adopted under this section;
(b) To enter the premises of a public water supply, or part thereof, to inspect the facilities and records kept pursuant to rules promulgated by the commissioner, to conduct sanitary surveys and investigate the standard of operation and service delivered by public water supplies;
(c) To contract with community health boards as defined in section 145A.02, subdivision 5, for routine surveys, inspections, and testing of public water supply quality;
(d) To develop an emergency plan to protect the public when a decline in water quality or quantity creates a serious health risk, and to issue emergency orders if a health risk is imminent;
(e) To promulgate rules, pursuant to chapter 14 but no less stringent than federal regulation, which may include the granting of variances and exemptions.