Thruscross Reservoir is the northernmost of four reservoirs in the Washburn Valley, lying north of Otley and west of Harrogate in North Yorkshire, England, near the hamlet of Thruscross. It can be found on an unclassified road from the A59 road. Permission to construct the reservoir was granted to Leeds Corporation Waterworks via the Leeds Water Order 1960 and Thruscross was completed in 1966, much later than the other three reservoirs which date back to the nineteenth century.