 At Kaufmann 's request , Denver artist Allen <unk> True was hired to handle the design and decoration of the walls and floors of the new dam . True 's design scheme incorporated motifs of the <unk> and <unk> tribes of the region . Although some initially were opposed to these designs , True was given the go @-@ ahead and was officially appointed consulting artist . With the assistance of the National Laboratory of Anthropology , True researched authentic decorative motifs from Indian sand paintings , textiles , <unk> and ceramics . The images and colors are based on Native American visions of rain , lightning , water , clouds , and local animals — lizards , serpents , birds — and on the Southwestern landscape of stepped <unk> . In these works , which are integrated into the <unk> and interior halls of the dam , True also reflected on the machinery of the operation , making the symbolic patterns appear both ancient and modern . 
