Optimal’s team has strong leadership is mobile, responsive, talented and enjoys a collaborative culture. Our flexible workforce is supported by key sub-consultants, suppliers and dedicated sub-contractors with like goals for our industry.

Murray Powell

Murray Powell

Managing Director Principal Auditor
Omid Sayar

Omid Sayar

Partner - Process & Operation Engineering Manager
Dr. Guy Amos

Dr. Guy Amos

Civil, Environmental & Waterways Engineer & QA Manager
Hugh Williamson

Hugh Williamson

Design Manager & Construction Manager
Steve Darwent

Steve Darwent

Manager Victoria / South Australia
Sash Nasiri

Sash Nasiri

Electrical & Instrumentation Manager
Arash Sajedi

Arash Sajedi

Manager - Operation and Maintenance
Mahnoush Najmi

Mahnoush Najmi

Senior Process & Operations Engineer - Victoria
Daniel Rhodes

Daniel Rhodes

Manager Queensland
Hamed Mootabadi

Hamed Mootabadi

Process and Operation Engineer
Darren Hanley

Darren Hanley

Construction Manager
Dr. Ahmad Hosseinzadeh

Dr. Ahmad Hosseinzadeh

Process and Operations Engineer - NSW/ Victoria
Dr. Morteza Afsari

Dr. Morteza Afsari

Process and Operations Engineer
Sujana Bajracharya

Sujana Bajracharya

Drafting & Documentation Manager - Victoria
Vahid Golkarian

Vahid Golkarian

Electrical Service Engineer
Ian Teh

Ian Teh

Senior Project Manager
Rasool Doraghi

Rasool Doraghi

Process and Operation Engineer
Dinh Tran

Dinh Tran

Senior Design Drafting
Harry Maher

Harry Maher

Water Engineer
Miyuki Ochi

Miyuki Ochi

Civil Drafter
Alex Klimenkov

Alex Klimenkov

Graduate Engineer
Mohammad Rasti Lari

Mohammad Rasti Lari

Mechatronic Engineer
Thomas Stangroom

Thomas Stangroom

General Hand
Murray Powell
Murray Powell
Managing Director Principal Auditor

Bachelor of Chemical Engineering & Masters in Business Administration

Murray has dedicated his career to the advancement of the stormwater industry. Murray has a deep commitment to protection of the environment and his passion for improved stormwater management is relentless.

Murray spent his early career with the NSW EPA as a stormwater compliance officer auditing industrial facilities. Following this he joined CDS Technologies as business development manager. This role provided Murray with a platform to embark on an outstanding career in the industry. Following transitional roles with Rocla Pipeline Products and consultants Hugh Trumen Murray was invited to form Optimal Stormwater in 2009.

Murray has skills and experience in all facets of stormwater management, with specialist expertise in stormwater treatment, auditing and stormwater harvesting. He has been involved with the sizing, siting and design of almost thousands of GPTs both locally and internationally. He has developed new models of gross pollution traps, trash racks and stormwater harvesting off takes.

He has mentored practitioners and designers internationally in all aspects of GPT design, and has a comprehensive knowledge of all GPTs available in Australia. He has written GPT design guidelines for several Councils, and presented several technical papers on multiple aspects of stormwater treatment.

Murray has been involved in over 40 stormwater harvesting systems, including investigations, feasibility studies, concept design and detail design, to construction and also operation.

Omid Sayar
Omid Sayar
Partner - Process & Operation Engineering Manager

Bachelor of Chemical & Process Engineering.

Master’s in Environmental Engineering (Water, Wastewater and Waste Engineering) at UNSW

Master’s in Engineering Management (Waste and Pollution Management) at UTS

Omid is Optimal Stormwater’s process & operations engineering manager with +10 years invaluable process and treatment expertise in all aspects of wastewater and stormwater. He has undertaken several optimisation studies of stormwater & wastewater treatment plants in Australia, and working as the operations engineer and facing operational problems has provided Omid with the skills and knowledge not only to fix and optimise the process but also to avoid issues on design side of the new projects.

He has a combination of academic qualifications, (an engineering degree and two Masters degrees), solid communication skills, and real field experience. This has led to considerable operational management skills. Omid has the aptitude for practical designs, validation, and effective optimisation of waste treatment and stormwater treatment systems. Omid’s skills dovetail through his incredible understanding of all things water quality, mechanical, electrical and process. He will not only manage this project but provide trouble shooting advice on-the-spot to enhance each system’s performance. Beyond that he can scope the process needs of any future optimisation and work-forward plan. Omid is a Part-time Industrial University Lecturer at UTS for decentralised environmental systems. He is the SWH consultant for the ACT Government and is highly regarded around the stormwater industry, having presented several papers on stormwater harvesting.

Omid leads a team of engineers and technicians that operate well over 100 sustainable water projects for many Council’s in NSW, ACT and Victoria. He is passionate about saving water and producing reliable and practical schemes for our clients.

Dr. Guy Amos
Dr. Guy Amos
Civil, Environmental & Waterways Engineer & QA Manager

BE Civil & MS Environmental Engineering. PhD Water Resources Management

Guy is new to Optimal Stormwater, joining in April 2016 after 15 years in local government where he was Stormwater & Waterways Manager for the southern Sydney suburb of Sutherland Shire, the second largest council in NSW.

Under his direction his team was responsible for delivering stormwater management services, which included: new capital works; maintenance; forward planning; asset management; floodplain/estuary management; watercourse management; policy development and customer service.

As manager, Guy constructed a large number of varied stormwater quality improvement projects and was responsible for managing almost 300 across the Shire. Guy brings a wealth of skill and knowledge in working with local government, understanding the policies and practices. His expertise in project management enable him to coordinate and deliver sustainable solutions to the client on-time and within budget.

Guy originally from the United States earned his BE and MS, before coming to Australia in early 1990s. He completed a doctorate under Professor John Argue of the Urban Water Resources Centre, University of South Australia. Guy developed a ‘best practice’ water management strategy for Portland Aluminium (ALCOA), VIC, which at the time was the single largest earner of export dollars in Australia.

Hugh Williamson
Hugh Williamson
Design Manager & Construction Manager

Hugh is a diligent and passionate environmental engineer and enjoys working on projects with positive environmental and sustainability outcomes. He is dedicated to delivery of high quality design and construction. Hugh has excellent communication with clients and provides clients the best service.

Hugh is competent with all modelling tools including MUSIC, DRAINS, HECRAS, TuFlow and drafting in CAD.

Hugh graduated in 2011 from RMIT University in environmental engineering and worked at Melbourne Water as project & investigation engineer in the flood mapping and mitigation and land development teams from 2011 to 2013.

He has previously worked in local government in the capital works and assets planning investigations director of engineering for Ernest landscaping based in Melbourne’s western suburbs.

Hugh has published 3 papers on the topic of ‘stream daylighting’ and 1 paper on stormwater harvesting design in Wonthaggi for a combined Optimal Stormwater & Bass Coast Shire Council Project.

Steve Darwent
Steve Darwent
Manager Victoria / South Australia

Steve joined Optimal Stormwater at the start of 2020 with the aim to offer Optimal Stormwater services to Victoria and South Australia. He comes from an international company background having worked with Esso Australia for 7.5 years in a senior management position. After the eventual sale of the downstream division of Esso due to the running aground of the oil tanker Valdez, Steve with others set up a stormwater treatment company in 1999.

Environmental Solutions (Aust) Pty Ltd started from small beginnings to end up working with many Government instrumentalities, Councils, Developers and private concerns. Clients included, Melbourne Water, Melbourne City Council, many Victorian Councils and Shires, Engineering companies, Water Catchment Boards, The City of Adelaide and many councils throughout South Australia. Work was also extensively done with authorities in Queensland, New South Wales, Tasmania, Northern Territory, Western Australia and ACT. During this time ES designed and constructed a variety of solutions in the gross pollutant trap industry.

Steve has had many years of experience in the design and installation of Gross Pollutant Traps for urban and wetland areas in all states and territories of Australia. Further to this, Steve has had experience in containerised water desalination and water security by way of HDPE dam lining and enzyme based compaction techniques. Steve is an experienced project manager and also has a wealth of experience in road sub-structure stabilisation.

Sash Nasiri
Sash Nasiri
Electrical & Instrumentation Manager

Sash is a dynamic and highly experienced Electrical and Instrumentation Manager with over 15 years of expertise in the field. He has acquired valuable knowledge working across various industrial sectors, including oil refineries and water and wastewater treatment plants. Sash specializes in a wide range of skills critical to the role, such as troubleshooting complex electrical and instrumentation issues, developing and implementing effective preventive maintenance schedules, and overseeing industrial equipment testing and commissioning. His exceptional proficiency lies in managing and programming Programmable Logic Controllers (PLCs), Human-Machine Interfaces (HMIs), and Supervisory Control and Data Acquisition (SCADA) systems. With his in-depth control and programming experience, Sash ensures seamless operations and optimal performance in electrical and instrumentation systems under his supervision.

Arash Sajedi
Arash Sajedi
Manager - Operation and Maintenance

Bachelor of Engineering Science,

Arash is our Process/Mechanical Engineer with more than 15 years of experience in commissioning and operation of large fixed and rotary equipment units in refineries and large water and wastewater treatment facilities. He has got thorough knowledge of routine operation and maintenance of treatment equipment and has successfully serviced and maintained a wide range of equipment and instruments such as pumps, turbines, compressors, aerators, media filters, membrane, and water quality monitoring stations.

Arash has completed extensive safety courses and will be responsible for organising and supervising the maintenance works. He is the work supervisor for Parramatta, Mosman, and Georges River Councils.

Mahnoush Najmi
Mahnoush Najmi
Senior Process & Operations Engineer - Victoria

Bachelor of Chemical Engineering

Masters of Chemical Engineering

Mahnoush is a highly skilled process and operations engineer with a deep-rooted academic and research background, having served as a wastewater research engineer in prestigious institutions like UCESCO and Deakin University. Her unique blend of theoretical knowledge and practical experience in the field of wastewater treatment, especially in water recycling and stormwater harvesting design projects, make her an invaluable asset to Optimal. Her academic insight, coupled with her practical approach, makes Mahnoush an instrumental figure in our team. With her ability to adapt to various project needs and her keen eye for detail, she embodies the innovation and dedication that underpin our operations at o Optimal.

Daniel Rhodes
Daniel Rhodes
Manager Queensland

Bachelor of Civil Engineering

Dan joined Optimal Stormwater as a Civil/Water Engineer in 2018. Since his commencement he has been working on watermain design and project management including overseeing drainage construction works on behalf of different Councils around Sydney.

Dan has also done extensive work with GPTs with Willoughby, SOPA and Randwick Council including design, auditing and rectifications of their existing devices. Most recently, Dan has been managing and producing on the Canberra GPT Audit, with excellent outcomes.

Dan is a passionate stormwater engineer with excellent communication skills who is not afraid to get his hands dirty in the field. This combined with great engineering knowledge makes him a valuable asset to the Optimal team. Dan is also lightning fast on a computer and a whiz with spreadsheets and information management.

Hamed Mootabadi
Hamed Mootabadi
Process and Operation Engineer

Bachelor of Chemical Engineering

Masters of Chemical Engineering – from Sydney University

With a strong foundation in Chemical Engineering, backed by a Bachelor’s and a Master’s degree from Sydney University, Hamed stands as a key member of Optimal team. As a process and operations engineer, he brings in  years of experience in manufacturing process control, enriched by his past experience as an operator in NSW’s chemical processing plants.

With his keen insight and dedication to delivering optimal results, Hamed will be a dependable ally in achieving the project’s objectives, ensuring it’s delivered on time and within budget. His dedication and professional acumen add great value to our team and guarantee the provision of top-tier service to our clients

Darren Hanley
Darren Hanley
Construction Manager

Murray Powell, General Manager of Optimal Stormwater has worked with Darren Hanley in a civil construction capacity since 1996. He has proven to be an excellent director of his own company and is now our dedicated Construction Manager.
Darren has been involved in construction of stormwater infrastructure for the last 25 years with a focus on Gross Pollutant Traps (GPTs) and CDS Units in particular. When Rocla (manufacturer of the CDS Unit) are asked by customers who they should contact concerning installation of a newly purchased device, they recommend Darren.
Over the past two decades many hundreds of GPTs have been installed in the Sydney region. A significant number of these devices have not had the benefit of adequate master planning and/or rigor in design, location and construction. Darren has gained considerable expertise in rectifying all manner of faulty devices, including; screen repairs and replacement; diversion weir modifications; lid repairs and replacement; access improvements and other specialist rectifications.
Darren brings a dose of practicality to every construction project Optimal Stormwater undertakes, making sure it is done in the most efficient way and with the least complication. He invariably anticipates potential issues BEFORE they occur.
Darren is responsible for all of Optimal Stormwater’s plant/equipment, keeping an up-to-date asset register and ensuring that everything is serviced and/or replaced when necessary.
Darren has no university qualifications, but real-life project management and construction experience that could not be gained in a classroom. His formal competences include:
• SafeWork NSW General Construction Induction Card (i.e. White Card)
• Certification to Enter and Work in Confined Spaces
• Certification to apply Traffic Control Plans
• Excavator operator license
• Expert welding skills

Dr. Ahmad Hosseinzadeh
Dr. Ahmad Hosseinzadeh
Process and Operations Engineer - NSW/ Victoria

Bachelor of Chemical Engineering

Masters of Chemical Engineering

PhD of Chemical Engineering

Ahmad is a senior process and operations engineer with more than 8 years’ experience in the process engineering field. He is the lead process engineer for our wastewater treatment and recycling projects. Ahmad has worked on many chemical process plants in Australia and oversees and is experienced in leading process engineering teams and delivering high end process design solutions.

Dr. Morteza Afsari
Dr. Morteza Afsari
Process and Operations Engineer

Morteza, equipped with a PhD in Chemical Engineering from UTS, serves as a senior process and operations engineer with Optimal, leveraging more than 8 years of experience in the process engineering field. Specialising in leachate and wastewater treatment and recycling projects, Morteza has honed his expertise through extensive work on various chemical process plants throughout Australia. His proficiency lies in the operation, monitoring, and troubleshooting of biological treatment systems. Currently, Morteza is the primary operator for remote monitoring and process adjustments for the Hurstville Leachate Treatment Plant, Gordon and Turra Leachate and sewerage treatment systems, as well as the North Sydney Water Recycling Infrastructures.

Sujana Bajracharya
Sujana Bajracharya
Drafting & Documentation Manager - Victoria

Diploma of Civil Engineering Masters of Professional Accounting

Sujana is a credit to the Optimal team and has been working as a civil, structural and water drafter for 10 years and as a drafting manager for 5 years. She has worked on large hydropower plants in Nepal, small, medium and large scale architectural projects in Sydney and gross pollutant traps for Rocla all over Australia.

Sujana previously undertook the design and drafting of stormwater quality treatment devices and her initials are still on the Rocla standard drawings. She has significant experience in using AutoCAD, Revit and Microsoft excel. She has meticulous attention to detail and is a very welcome and excellent addition to the Optimal Stormwater team. Sujana is competent in DRAINS, CAD, HECRAS

Vahid Golkarian
Vahid Golkarian
Electrical Service Engineer

Grade A Electrician (Licenced)

Bachelor in Electrical Engineering

Vahid is a key member of the Optimal team as our diligent Electrical Service Engineer and a Certified Electrician. He boasts an impressive and extensive 18-year career in the wastewater industry, coupled with a Bachelor’s degree in Electrical Engineering. His professional journey has been punctuated with accomplishments in the design, construction, and maintenance of electrical equipment, each of which testifies to his technical prowess and unparalleled expertise.

Ian Teh
Ian Teh
Senior Project Manager

Ian is currently a Senior Project Manager at H&H with over 15 years’ experience in Project Management, Design and Construction. Before joining H&H he worked as a Construction Manager (Landscape and Civil works) at Regal Innovations for Council and Tier 1 Contractors. Prior to this he was a Project Manager at City of Sydney Council for 9 years managing various projects from design to construction. These projects included water harvesting projects, landscape, civil, electrical, heritage and artwork projects. His specialty in design and construction management has enabled him to be able to manage Client relationships, stakeholders, project teams, consultants, contractors and suppliers to ensure project requirements are being met.

 

  • Harold Park, Jubilee Oval and Federal Park Water Harvesting, Glebe – Feasibility study, concept design, detailed documentation and tender documentation.
  • Waterloo Oval Stormwater Harvesting Scheme, Waterloo – Feasibility study, concept design, detailed documentation, tender documentation, and construction.
  • Water re-use Feasibility Studies for 8 sites across City of Sydney LGA. Three sites were later further developed, detailed and constructed. These were Alexandria Park, Pirrama Park, and Waterloo Oval stormwater harvesting schemes.
  • Johnston’s Canal Shared Path Project, Forest Lodge/Glebe – Detailed documentation, tender documentation, and construction.
  • Park Signage Program – The design and programmed roll out of park signage and way finding signage across the LGA
  • Quarry Green Upgrade, Ultimo – Construction works for a new 10km/h shared zone on Bulwara Road Ultimo
  • Blue Street and Miller Street Public Domain Upgrade, North Sydney – Construction works for the upgrade of Blue Street and Miller Street North Sydney.
  • UTS Central, Ultimo – Civil and landscape construction works for Building 02 for UTS.
Rasool Doraghi
Rasool Doraghi
Process and Operation Engineer

Bachelor of Chemical Engineering

Rasool is a highly skilled service engineer at Optimal, bringing a wealth of more than 15 years of invaluable experience in operation, maintenance, and commissioning of complex water and wastewater systems. His rich experience stems from his active involvement in substantial EPC (Engineering, Procurement, and Construction) projects. Rasool’s project portfolio is impressive, encompassing a wide range of systems such as Sea Water Pump Stations, Utility Water Systems, and Wastewater Treatment Packages.

Dinh Tran
Dinh Tran
Senior Design Drafting

Dinh is Optimal Stormwater’s senior civil design drafter. Dinh has excellent skills and has prepared documentation for stormwater quality treatment devices, stormwater harvesting designs, potable water mains, sewer reticulation mains and civil works. He is an excellent worker in the Optimal Stormwater drafting team and is now picking up design elements.

Harry Maher
Harry Maher
Water Engineer

Bachelor of Civil Engineering – BEng – (University of Technology, Sydney) Bachelor of Business – BBus – (University of Technology, Sydney)

 Harry joined Optimal Stormwater in 2023, having completed his Bachelor of Civil Engineering and Bachelor of Business from the University of Technology Sydney in November 2018. Harry has had experience across the various parts of the stormwater industry, working as a Civil Engineer since 2018. Harry has had several years of Engineering experience working in the Local Government sector as a Project Engineer on Water and Environmental projects.

Harry is a dedicated professional with a passion for water resource management and environmental sustainability. He thrives in environments where he is able to build relationships and foster positive work outcomes. Harry has exceptional communication skills combined with his enthusiasm for environmental outcomes.

Harry has been involved in:

  • Extensive Hydraulic modelling experience with DRAINS software.
  • Auditing of GPTs and WSUD assets for Councils across Australia
  • Investigating flooding problems through both a practical and numerical approach. Constructing reports, developing concept solutions and cost estimates for a range of project types.
  • Producing Data sheets, Cleaning Specifications and O&M Manuals for numerous GPTs and WSUD assets.
  • Project Management across a range of environmental and construction projects
Miyuki Ochi
Miyuki Ochi
Civil Drafter
Alex Klimenkov
Alex Klimenkov
Graduate Engineer

Bachelor of Civil and Environmental Engineering (Honours) – University of Technology Sydney
Alex joined Optimal Stormwater in December 2021 as an undergraduate engineer, and has since been kept on the team as an engineer after he completed his studies in August 2023.
He often works on generating catchment maps, audit reports, data sheets, and cleaning specifications for GPT and WSUD auditing projects. As of late, Alex has been developing DRAINS models for a variety of projects ranging from proposed GPT projects to flood modelling. He is also commonly tasked with writing hydraulic and concept design reports following the results of his water modelling efforts, where his strengths in report writing and presentation are apparent.
Since joining Optimal, he has attained Confined Spaces Training and has become a Transport NSW Accredited Culvert Inspector. His key strengths lie in his enthusiastic approach to every job, comprehensive report writing ability, and swift development of skills using engineering software.

Mohammad Rasti Lari
Mohammad Rasti Lari
Mechatronic Engineer

Mohammad holds a key position within our team as a Mechatronic Engineer and Service Technician. He brings to the table a Bachelor’s degree in Mechatronic Engineering from UTS along with a Low Voltage Disconnect Reconnect Certificate, making him well-versed in the intricate aspects of engineering that are necessary for our diverse projects.

Thomas Stangroom
Thomas Stangroom
General Hand