About Us


Indigo Water Group is a self-certified Woman Owned Small Business Enterprise based in Littleton, Colorado. We specialize in water and wastewater treatment projects and have been involved in numerous projects from planning through permitting and construction.

Indigo Water Group focuses on services in key areas including utility planning, biological process and collection system modeling, regulatory assistance, comprehensive performance evaluations, process assistance and plant optimization, and operator training. We have recently added contract operations for small wastewater systems to our list of services.

Sidney Innerebner, PhD, PE, CWP

Sidney has over twenty-eight years of experience in environmental services including laboratory management, treatment plant operation, and water and wastewater design.  She has conducted training classes throughout her career beginning with chemistry and lab techniques at Rocky Flats.  She has served as an instructor at the Leadville Operators School, Fundamentals School, and Boulder Operators School for many years.  Additionally, Sidney has been an invited guest lecturer at the Colorado School of Mines, Red Rocks Community College, and Ohio Water Environment Federation.

Sidney has had an unusual career path starting as an environmental chemist at Rocky Flats (a nuclear weapons manufacturing facility long since closed) and then moving on to work at the Littleton/Englewood wastewater treatment plant.  There, she gradually moved into operations while continuing to work as a chemist and attending school at night to become an engineer.  Sidney received the Analytical Merit Award in 2000 for Colorado from the RMWEA.  Sidney graduated from the Colorado School of Mines in 2001 with a PhD in Environmental Science and Engineering.  Her graduate research focused on nitrifying bacteria and biofilms.  She is a certified wastewater operator in Colorado and holds level A Industrial and A Municipal licenses.  She is certified as a Grade IV Professional Operator. She specializes in biological treatment processes, nutrient removal, operations troubleshooting and streamlining, operations training, and assisting with laboratory setup and training.  She has two biological children, both boys, aged 4.5 years and 24 years.  Yes, she is crazy.  Sidney has had many wonderful mentors over the years who always made time to teach her new things.  Many of them were and continue to be active volunteers with Water Environment Federation.

Sidney has developed numerous operations training programs and gives training classes and seminars across the United States.  She has expertise in planning, biochemical treatment processes, comprehensive performance evaluations, wastewater process modeling, laboratory operations, environmental assessments, environmental permitting and compliance, chemistry, and toxicology.

  • Principal/Owner

  • 25+ Years Experience

  • BS Chemistry

  • BS Microbiology

  • MS and PhD Environmental Science and Engineering

  • Colorado A Wastewater Operator

  • Colorado A Industrial Operator

  • Professional Engineer in State of Colorado

  • Resume
Ever wonder why our logo looks the way it does?  Indigo’s logo is a representative of a water hyacinth.  These useful plants are used in natural wastewater treatment systems.  The outer circle represents the water cycle.

Our name is a nod to the industry convention of color coding potable water as blue and reuse water as purple.  We spend most of our time somewhere in between.