About Us: Quiddity is an award-winning, full-service civil engineering, planning, surveying, and professional consulting firm assisting public and private sector clients in the design, development, implementation, and execution of infrastructure projects. For over 45 years, we have assisted our clients in various projects, including water and wastewater treatment plants, storm drainage, transportation, planning, construction management, and surveying. We have 11 locations across Texas: Houston, ...