Water purification and storage system, water-filtering well and polygonal building block

A water purification and storage system comprising:

• a water storage container formed by:
• a plurality of tangentially connected water-filtering wells (1) having well walls made of a water-permeable structure, and
• an anti-leakage layer (4) arranged on the well bottom,
• at least one of the water-filtering wells (1) is a water output well (14);
• the well walls of the water-filtering wells (1) include a multilayer of spliced hexagonal subunits (11);
• each hexagonal subunit (11) is orthohexagonal and includes six spliced building blocks (12) of the same size and the seams of the building blocks (12) of adjacent layers are misaligned;
• an inner catching groove (121) is provided at one side of a long edge of the building block (12) and adapted for insertion of a side wall of adjacent building blocks (12), the side wall of one said building block (12) is adhesively connected to the inner catching groove (121) of a next building block (12), and the long edge of the building block (12) forms an inner wall enclosing the water-filtering well (1), and a short edge and side wall of the building block (12) forms an outer wall enclosing the water-filtering well (1);
• a covering plate (2) arranged at an upper portion of the water storage container, said covering plate (2) comprising an impermeable covering plate (21) arranged at the upper portion of a water output well (14) and water-permeable covering plates (22) arranged at upper portions of other water-filtering wells;
• and
• a diaphragm wall (3) arranged around the water storage container.