Treatment Plant Estimator - CIG

Based in St. Louis, Core & Main is a leader in advancing reliable infrastructure™ with local service, nationwide®. As a specialty distributor with a focus on water, wastewater, storm drainage and fire protection products and related services, Core & Main provides solutions to municipalities, private water companies and professional contractors across municipal, non-residential and residential end markets, nationwide. With over 370 locations across the U.S., the company provides its customers local expertise backed by a national supply chain.

Core & Main’s 5,700 associates are committed to helping their communities thrive with safe and reliable infrastructure. Visit to learn more.

The Estimator – Critical Infrastructure Group (CIG) supports the development of quantity takeoffs for critical infrastructure projects under direct guidance from senior estimating personnel. This role focuses on learning plan interpretation, material identification, and basic takeoff procedures. The estimator collaborates with the Pre‑Bid team, sales team, and other estimators to ensure accurate, timely bid support while building foundational estimating skills.

• Assists in reviewing construction plans and specifications to identify basic material requirements.
• Performs entry-level quantity takeoffs with supervision and guidance.
• Identifies standard materials and components needed for infrastructure systems.

• Supports the preparation of scopes and basic bid packages.
• Works with the Pre‑Bid team to confirm scope details and gather required information.
• Communicates with internal team members to clarify basic project elements.

• Participates in training sessions to build proficiency in takeoff software, product knowledge, and plan reading.
• Works closely with higher-level estimators to learn best practices, workflows, and company procedures.
• Accept feedback and coaching to improve accuracy and efficiency.

• Strong willingness to learn and develop technical skills.
• Attention to detail.
• Basic problem‑solving abilities.
• Effective, professional communication.
• Good organizational skills and ability to follow established processes.

• 5 years prior experience specific to bid preparation, sales, or construction.
• Bachelor’s degree in a construction management or engineering discipline.
• Typically requires BS/BA in a related discipline.
• Generally, 5-8 years of experience in a related field; certification is required in some areas OR MS/MA and generally 3-5 years of experience in a related field.
• Certification is required in some areas.

• 0–2 years of experience in construction, engineering, or related fields.
• Exposure to reading blueprints or construction documents preferred.
• Prior internship, training, or coursework in construction or engineering is a plus.

• Associate degree or technical certificate preferred.
• Coursework in Construction Management, Engineering, or related fields beneficial.
• Equivalent experience considered.

Core & Main is an Equal Employment Opportunity employer. Employment at Core & Main is based solely on a person’s merit and qualifications directly related to professional competence. Core & Main does not discriminate against any employee or applicant on the basis of race, creed, color, religion, national origin, nationality, ancestry, age, disability, veteran status, pregnancy or related condition (including breastfeeding), affectional or sexual orientation, gender identity or expression, marital status, status with regard to public assistance, citizenship, or any other basis protected by law.
None of the questions in this application are intended to elicit information regarding any protected characteristics, nor imply any limitation, illegal preferences or discrimination based upon non-job-related information or protected characteristics.