The Role
With a strong pipeline of projects and continued growth across Australia, Guidera O'Connor is seeking a Graduate Estimator to join our Core Bid Team based in Thebarton.
This is an exciting opportunity for a recent Mechanical or Chemical Engineering graduate or a Construction Management graduate to gain hands-on experience in estimating and bid development within a highly specialised industry.
Working closely with experienced Estimators and the Lead Estimator, you will contribute to the preparation of competitive project bids while developing valuable technical, commercial, and stakeholder management skills.
You will play a key role in supporting the estimating process, engaging with suppliers and subcontractors, reviewing project documentation, and assisting with the development of accurate project cost estimates.
You will work alongside and be supported by a team of experienced professionals, united by Guidera O'Connor's five guiding principles: Care, Integrity, Passion, Respect, and Future.
Key Responsibilities
Assist with quantity take-offs from engineering drawings and project documentation
Prepare and issue requests for quotation (RFQs) to suppliers and subcontractors
Assist with supplier comparison evaluations and estimate preparation
Support the development of accurate project cost estimates and bid submissions
Build and maintain strong relationships with suppliers and subcontractors
Support the preparation of resource schedules, rates, and cost models
Contribute to meeting bid deadlines while maintaining a strong focus on quality and accuracy
Develop a thorough understanding of estimating processes within the water and construction sectors
About You
You are a motivated engineering graduate who enjoys problem-solving,



working with numbers, and collaborating with others to achieve successful outcomes.
Highly organised and detail-focused, you can manage competing priorities and work effectively to deadlines.
You are eager to learn, comfortable communicating with a wide range of stakeholders, and looking to build a long-term career in project estimation and construction.
You will ideally bring:
A degree in Mechanical or Chemical Engineering, or Construction Management
Excellent numerical, analytical, and problem-solving skills
Strong communication and relationship-building abilities
A proactive attitude and willingness to learn
The ability to manage multiple priorities while maintaining attention to detail
Exposure to construction, infrastructure, or the water industry (desirable but not essential)
Guidera O'Connor is an equal opportunity employer.
If you meet most, but not all, of the criteria we'd still love to hear from you.
About Us
From desalination plants providing clean water to Australian communities, to treatment facilities that return wastewater safely to the setting, Guidera O'Connor designs and delivers tailored solutions that make a real difference to people's lives.
Guidera O'Connor designs, constructs, and commissions:
Water treatment plants
Pumping stations
Chemical dosing systems
Filtration
Desalination plants




Aquifer storage and recovery
Reuse systems
We work with customers across Australia, including:
Water authorities
Local government
Mining and resources companies
Private asset owners
Head contractors
Engineering organisations
Our business is founded on five guiding principles: Care, Integrity, Passion, Respect, and Future, each of which inform our collaborative, innovative, solutions-focused approach.
More than infrastructure, we deliver value, creating the systems that make protected, clean water possible for people and communities across the country, now and into the future.
Our Benefits
In return for your skills and experience, we offer a supportive team environment, strong leadership, and meaningful work that contributes to essential infrastructure.
Our benefits include:
Free onsite parking
Daily office lunches provided
Flexible working arrangements
Additional annual leave for service milestones
15 days personal leave
Company-funded wellbeing program
Paid parental leave
Diversity & Inclusion
At Guidera O'Connor, we value a diverse, inclusive, and respectful workplace.
We strongly encourage applications from people of all backgrounds, regardless of age, gender, culture, or identity.
As part of our commitment to gender equity, we aim to increase the participation of women in the construction industry and encourage applications from women for all roles.
As part of our Reconciliation Action commitment, we also strongly encourage applications from Aboriginal and Torres Strait Islander peoples.
Apply
Please apply online
For further information, please contact the People & Culture team at ******

📌 Graduate Estimator (South Australia)
🏢 Guidera O'Connor
📍 South Australia