Tribal Access to Clean Water Act of 2021 This bill provides funding for and expands access to water resources for Native communities (i.e., Indian tribes and Native Hawaiian communities). First, the bill provides funding for the Indian Health Service to (1) plan, design, construct, modernize, improve, and renovate water, sewer, and solid waste sanitation facilities; (2) provide technical assistance; and (3) operate and maintain water facilities that serve Native communities. Next, the bill provides funding for the Department of Agriculture to provide water and wastewater facility grants to eligible entities (e.g., Native communities) that have residents facing significant health risks due to inadequate water supply systems. An eligible entity shall not be required to provide a matching contribution in order to receive a grant. In addition, the bill reauthorizes through FY2031 the Bureau of Reclamation's Rural Water Supply Program. Further, the bill provides funding for and establishes a grant program for tribal clean water access projects. It also provides funding for the Native American Affairs Technical Assistance Program. The bill also provides funding for the Environmental Protection Agency to provide grants to Indian tribes and Alaska Native villages for drinking water and clean water.