Clean Water Infrastructure Act This bill amends the Safe Drinking Water Act to reauthorize through FY2022 and revise the drinking water state revolving fund (SRF), including to require SRF-funded projects to use iron and steel produced in the United States. The bill revises requirements for state Intended Use Plans for SRF funds, including to require the plans to: (1) list systems that are not in compliance with national primary drinking water regulation, (2) reserve a specified amount of funding for assistance for disadvantaged communities, and (3) prioritize SRF funding by those communities. The bill repeals: (1) requirements for regulations on variance technologies, and (2) state authority to exempt small public water systems from national primary drinking water regulations if the system installs certain treatment techniques. The Environmental Protection Agency must: prescribe follow up inspections after violations by public water systems, establish requirements for electronic submission of compliance monitoring data by public water systems, study the presence of pharmaceuticals and personal care products in drinking water sources, collect data on best practices for administration of SRF programs, implement a voluntary certification program for effective water loss and leak control technology, and submit a strategic plan for assessing and managing the risks of drought to drinking water provided by public water systems. Finally, the bill reauthorizes through FY2023 a grant program for certain lead reduction projects.