Executing the first Green Star-rated service station in Africa

By AECOM SA

The capability to offer a turnkey solution has resulted in integrated infrastructure delivery company AECOM designing and building a masterpiece for a premium fuel service station group on the N4 in Kroondal, in the North West Province.

The project brief called for an alternative to the European service station concept, to create a state-of-the-art retail fuel site that challenges the traditional view of a service station being a modular square box. Looking at the convential design, AECOM realised that they had scope to push the boundaries. Their multidisciplinary approach also allowed more innovation in their construction methodology.The project brief called for an alternative to the European service station concept, to create a state-of-the-art retail fuel site that challenges the traditional view of a service station being a modular square box. Looking at the convential design, AECOM realised that they had scope to push the boundaries. Their multidisciplinary approach also allowed more innovation in their construction methodology.

The site on the N4 highway is close to the town of Kroondal in the North West Province and is the first lightweight steel retail fuel station in the group’s network. The project is the group’s largest capex outlay on a retail fuel site in decades. 

The project commenced in September 2017 and was completed in October 2018. Delivery of the project was delayed due to unforeseen site conditions, abnormal rainfall, and community protests.

One of the most challenging elements of the design was the software modelling of the lightweight steel design. Continuous design reviews were required to ensure clashes would be kept to a minimum and that alignment with the architect’s design would be achieved.

 

Wet services of the project

Water sourceThe water source was the key contributing factor in the selection of a water-efficient design; the recycling of grey water, and the use of borehole water. A municipal water connection was not immediately available and the process to obtain such a connection was a long, drawn-out process. Therefore, other water sources, such as borehole water and recycling of grey water, were incorporated into the design, which will later become a supplementary water supply to the municipal water supply for the facilities. 

 

System/design intent

  • Water
    The design intent was to use the municipal water supply for domestic drinking water purposes on both the east and west building facilities. The urinals and WCs would receive recycled/treated grey water for flushing purposes. The goal was to reduce the use of the scarce freshwater resource (municipal water) and at the same time reduce the cost of the municipal water bill.
    There is an existing borehole with sufficient yield that has been considered into the design of the water supply. The borehole water requires treatment, and pending budget approval and the timing of the municipal water connection, this phase is yet to be implemented. Once approved, a water treatment plant will be constructed, and the borehole water will supplement the municipal water supply. The intention is to eliminate the risk of municipal water interruptions/shortages. 
  • Sewer
    The area has no bulk water-borne sewer connection, and therefore it was necessary to construct a sewer treatment plant on site. The raw sewage must be treated to a level that is acceptable to the Water Use Licence Agreement (WULA) document. The water is treated for reuse into the building ablutions for toilet and urinal flushing, with the safe excess discharged into the natural water courses.

 LightSteelGeberit

GeberitPipeSystem

The lightweight steel frame structure perfectly suited an in-wall system. In-wall concealed traps for the wash hand basins were used to obtain a clean architectural finish compared to the traditional rubber P trap or bottle trap.

System operation

There are three sectional steel storage tanks, namely domestic water; recycled water, and fire water. The domestic water storage tank of capacity 116m3 will receive potable water from the municipal water supply and then supply the facilities via a booster pump set. The borehole water, once implemented, will be treated to supply the domestic water tank. There will be allowance for controls for municipal and borehole water supply.

The soil and wastewater from the facilities will drain into the sewer treatment plant and be treated and stored into a recycled water storage tank of capacity 21.8m3. The water will then be supplied to the facility’s toilet cisterns and urinals for flushing via a booster pump set. A top-up water connection from borehole water supply has been allowed for.

A sectional steel storage tank of capacity 174m3 for the fire water, which has its own pump sets as per fire regulations, is also installed. 

 

Reticulation

To ensure safe water use inside the buildings, dual reticulation lines for recycled water and potable water were installed using Mepla pipes. The reason for choosing the Mepla solution was due to its low theft value, quick installation, suitability for the lightweight steel structure due to non-conductivity between the metals, and its performance reliability for both hot and cold-water use.

 PumpSet2

The pump sets installed at the storage tanks.

Hot-water generation and circulation

The hot-water generation allowed for two heat pump and storage systems. Each system comprises a 250ℓ Kwikot storage vessel inclusive of a 3kW backup element, with hot water primarily generated from a 5.5kW Kwikot heat pump. The hot-water reticulation forms a ring main with hot-water supply and return through the Magna 3 Grundfos circulation pump. The smart circulation pump was chosen because of its building management system (BMS) compatibility, its intelligence of profiling the user requirements/peak flows, and its low energy consumption/efficiency.

 20190423 085932

The completed installation of the domestic water storage tanks and the treated grey-water storage tanks.

Roof rainwater

Due to the architectural aesthetics of the building, the Pluvia system is used to drain the bulk of the roof rainwater to the rear end of the buildings. The water is then collected into plastic JoJo tanks for reuse by the retailer for gardening and other purposes.

Water-efficiency fittings

Where it was deemed practical, the water taps specified and installed in the public ablutions are all water-saving fittings from Grohe. The toilet cisterns throughout and the urinals in the male ablutions are Geberit concealed cisterns. The flush flow rates are set to minimise excess water wastage. This is in keeping with the Green Star requirements that the project aimed to achieve.The sanitaryware from Duravit was carefully selected to complement the low-flow cisterns and taps and, at the same time, to maintain a high aesthetic value as envisaged by AECOM architects.

The taps to the wash-hand basins and showers are fitted with Grohe thermostatic mixing valves to provide premixed water in order to prevent the wastage of hot water. The temperatures were set to 38 degrees Celsius in male ablution showers and 40 degrees Celsius in female ablution showers.

Helix 4000/5000 water meters were installed as primary meters for the building supply, with smaller meter sizes for submeters. The meters are connected to the BMS for monitoring and early leak-detection warning. This was also targeted at the required Green Star rating.

 

Green Star rating

The N4 Kroondal fuel station aims to achieve a 4-Star Green Star rating from the Green Building Council of South Africa, making it the first service station in South Africa to achieve such a prestigious accreditation. 
The ‘as built’ Green Star rating that the project is targeting, encompasses locally sourced materials, community facilities, indigenous planting, the recycling of construction waste, a structure that can be disassembled and reused to ensure reduced embodied energy and resource depletion through the concrete mix, and low VOC interior finishes, among others.

All grey and black water on site is filtered and reused in the toilets and urinals. The building is fully controlled and monitored via a BMS, while live energy- and water-use data is displayed in the shop area. Sewer treatment plant Full details of the on-site sewer treatment plant are available on request from AECOM. The plant is complete, including unit treatment processes, chemical dosing equipment, sludge treatment and handling, associated pumps, pipework, valves, and electrical and other ancillary equipment for the treatment of wastewater to specified standards.

 BathroomComplete

The completed toilets at the service station.

System’s impact on efficiency

Water- and energy-efficient designs and outcomes are in line with Green Star targeted credits. The estimated water savings are between 30 and 35% due to the recycling of sewer water for reuse and the minor contribution from rainwater harvesting for gardening or other uses.

The back-up water storage eliminates the risk of water interruptions and in turn, prevents business interruptions. The selected energy-efficient pumps could, in general, save up to 30% on energy consumption. 

Unique elements of the project

First fuel service station to be built with a lightweight steel structureFirst fuel service station to be built with a lightweight steel structurePotentially the first Green Star-rated fuel service stationComplete water-efficient design that is integrated with the BMS for monitoringReuses black water in the building, reducing pressure on municipal supply.
Geberit Southern Africa Pty Ltd OFC Plumbing Africa May 2019 20190423084336 47990 FINAL1

List of professionals Name of company
Project name Undisclosed
Owner Undisclosed
Developer Undisclosed
Architect / Designer AECOM
Project manager AECOM
Consulting engineers  
Electrical AECOM
Wet services AECOM
Civil AECOM
Mechanical AECOM
 
Contractors
Buildings Razorbill Eco-Construct
HVAC & R Improvair Environmental Solutions
Wet services (plumbing) Groenkor Plumbing and Drains
Electrical Southern Star Electrical
Water treatment Prentec
 
Products Suppliers
Roof stormwater drainage Geberit Pluvia
Cold, hot, and recycled water pipe reticulation Geberit Mepla
Hot-water vessel and heat pumps Kwikot
Pumps — water supply and hot-water circulation Grundfos
Sanitaryware and taps Duravit and Grohe
Drainage — uPVC soil and waste Marley
Sectional steel tanks ABECO
Grease traps Herbish
Plastic rainwater tanks JoJo
Water meters Elster Kent (Honeywell)

 

Advertising
Advertise on Plumbing Online

Click below to access the digital publication:

(please ensure you are registered and logged in first)
07 July PA250


PA PlumbdrainLogo100 PlumbingOnline150 TP

Product of

IMD logo White

Interact Media Defined (IMD), is one of South Africa’s leading multi-media magazine publishers READ MORE

Talk to us

JHB T : +27 (0) 11 579 4940
CPT T : 0861 727 663
E : admin@interactmedia.co.za

13A Riley Road, Bedfordview,
South Africa 2007

PRIVACY & COOKIE POLICIES

Cookie policy
Privacy & Cookie policy
Privacy policy

© Interact Media Defined