We proudly provide the best customer service in the industry! For more than 15 years, Lilly’s Septic Tank Services has provided its clients with quality, expert & thorough Septic System service. Based in King County, Lilly’s Septic Services handles both residential and commercial jobs ranging from Septic Tank cleaning and pumping, Locating and Digging Septic Tank lids, commercial grease trap cleaning, emergency repairs, Pump Replacements & New Septic System Installations.