Water Engineering and Conservation Solutions for UAE Projects

Water policy in the UAE is set at national level by the Water Security Strategy 2036. Its headline targets, as reported by The National, include a 21% reduction in total demand for water resources and an increase in the reuse of treated water to 95%. Buildings carry a large share of that demand, which is why emirate-level building regulations translate the national targets into design requirements.

In Dubai, the Al Sa'fat green building system sets fixture flow rates and adds mandatory requirements for any building that uses greywater or treated sewage effluent internally. Merka's guide to Silver Sa'fa water and envelope requirements covers the local baseline in detail. In Abu Dhabi, the Estidama Pearl Rating System applies its own water credits and minimum thresholds.

Many projects also target an international certification on top of the local system. LEED's Water Efficiency category rewards reduced indoor and outdoor use and requires water metering, and the article on LEED v5 credits for Gulf projects explains how those credits align with local rules.

Utility approvals complete the picture. Water connection, drainage and irrigation designs are reviewed by the relevant utility and municipality, so the plumbing and drainage layouts, meter locations and connection points need to follow authority standards from schematic design onwards.

The cheapest litre is the one a building never uses. Demand reduction comes first in any water strategy because it lowers the load on every downstream system: smaller tanks, smaller pumps, smaller pipes and smaller treatment plant.

Fixture selection delivers the largest and most reliable savings. Low-flow basin taps with aerators, low-flow showerheads, dual-flush WCs and waterless or low-flush urinals typically cut indoor potable use substantially compared with conventional fittings. The flow rates belong in the fixture schedule with manufacturer data sheets, and the specification should name the tested flow rate at design pressure so that substitutions can be checked quickly.

Pressure management is the second lever and the most often overlooked. Excess pressure increases flow at every outlet, accelerates wear on valves and raises leakage. High-rise buildings are divided into pressure zones served by booster pumps, break tanks and pressure-reducing valves, so each floor receives water within a controlled range.

A 30-storey residential tower illustrates the scale of that task. At that height the plumbing design typically needs several vertical pressure zones, with plant rooms and tank locations coordinated with the structural and architectural layout from concept stage.

Hot water design also affects consumption. Long pipe runs between a heater and an outlet waste water every time a tap runs until hot water arrives. Compact layouts, circulation loops with timed or temperature-controlled pumps, and point-of-use heaters for remote outlets all reduce that waste.

Metering makes savings visible and lasting. Sub-meters on major uses such as irrigation, cooling tower make-up, pools, kitchens and individual tenancies let facility managers spot leaks and abnormal consumption within days. Connected to the building management system, meters also provide the operational data that green building recertification relies on.

Once demand is reduced, the next step is to replace potable water with non-potable sources for uses that do not need drinking-water quality, such as irrigation, WC flushing and cooling tower make-up. Three sources dominate UAE practice.

Air-conditioning condensate is the most underused resource in the region. Air handling units and fan coil units that cool humid outdoor air extract large volumes of water, and the volume peaks in the most humid months, exactly when irrigation demand is highest. Condensate is low in dissolved solids, which makes it suitable for irrigation and cooling tower make-up with modest treatment. Coastal sites produce the most, and Merka's comparison of coastal and inland design conditions explains why humidity varies so much between plots.

Greywater from showers, baths and basins can be collected, filtered and disinfected on site for WC flushing and irrigation. Residential buildings generate greywater steadily, which suits a mixed-use development: the residential floors produce it and the commercial floors consume it for flushing. The Downtown Mixed-Use Tower concept, combining residential units, retail frontage and commercial space, shows the kind of programme mix that makes that balance work.

Treated sewage effluent (TSE) from municipal treatment plants is widely used for landscape irrigation and, in some districts, for district cooling. Where a TSE network reaches the plot, connecting irrigation to it removes the largest outdoor potable demand entirely.

Every non-potable system requires a separate, clearly identified pipe network, with colour-coded pipework, labelled outlets, backflow prevention and air gaps at every interface with the potable supply. Those requirements run through risers, plant rooms and ceiling voids, so they must be drawn and coordinated in the construction documentation for plumbing and drainage well before tender.

The decision to use greywater or TSE inside a building also triggers additional regulatory requirements for treatment, monitoring and labelling. Making that decision at schematic stage, while risers and plant rooms can still be sized, avoids expensive redesign later.

Outside the building envelope, two uses often exceed all indoor consumption combined: cooling towers and irrigation.

Water-cooled chiller plants lose water through evaporation, drift and blowdown. Evaporation is the price of efficient heat rejection, while blowdown is controllable. Raising the cycles of concentration through proper water treatment reduces blowdown volumes, and high-efficiency drift eliminators cut losses further. Feeding cooling towers with condensate or TSE removes much of the potable demand.

District cooling changes the equation for many projects. Where a district cooling provider serves the plot, heat rejection and its water use move off site, and the building's water design concentrates on the energy transfer station and the chilled water distribution.

Irrigation demand is decided by the landscape design. Native and adapted species, grouped by water need, combined with drip and subsurface irrigation, soil moisture sensors and weather-based controllers, reduce outdoor water use sharply compared with lawn-dominated schemes sprayed on fixed timers. Shade trees and planting also lower surface temperatures, and Merka's guide to cooling outdoor spaces through site layout shows how landscape and massing work together.

Landscaped residential communities show why irrigation strategy belongs in the master plan. The Dubai Hills Residential Terraces concept arranges mid-rise buildings with open terraces within a landscaped setting, and on a scheme of that kind, planting zones, irrigation mains, TSE connections and condensate collection points are all set out alongside the building layout.

Planted terraces and green roofs need their own detailing: root barriers, drainage layers, irrigation points and waterproofing that can be inspected and maintained. Designing them early keeps the structural loads, falls and outlets aligned with the landscape intent.

Rain in the UAE is rare, and when it arrives it can be intense. Short, heavy storms have repeatedly shown that roof outlets, podium drainage, ramps and basement entrances need to be designed for peak intensity, with overflow routes that protect the building when the primary system is overwhelmed.

Roof and podium drainage is sized to the design rainfall intensity, with secondary overflow outlets or scuppers on every roof area. Basement ramps need interceptor channels at the top and bottom, and sump pits with duty and standby pumps, connected to backup power, protect the lowest levels.

On larger plots, attenuation tanks or soakaways hold peak runoff and release it slowly to the network or the ground. Harvested stormwater can supplement irrigation, although its irregular supply means it works best as a top-up to condensate or TSE.

Groundwater is the other side of the water balance. Coastal and low-lying plots often have a high water table with aggressive chlorides and sulphates, which affects dewatering during excavation, basement waterproofing, uplift resistance and the durability of buried concrete. Merka's foundation and basement structural design addresses those conditions through appropriate concrete specifications, cover, waterproofing systems and permanent drainage or tanking.

Drainage and sewer connections require their own authority approvals, including connection permits and, on some plots, requirements for on-site pre-treatment such as grease interceptors for restaurants and oil interceptors for car parks. Merka coordinates those submissions through its permit and NOC management service alongside the building permit.

A water strategy only works when it is coordinated with every other discipline. Tanks and treatment plant need floor area, structural capacity and access for maintenance. Dual pipe networks need riser space and ceiling depth. Drainage falls need slab set-downs, and condensate collection needs a route from every air handling unit to a central tank.

Coordinated 3D models are the most reliable way to resolve those demands before construction. Merka's article on clash detection in multi-discipline models explains how gravity drainage, which cannot run uphill, is given priority in congested ceiling zones.

The wider picture of plumbing, drainage and fire protection within the MEP scope is covered in Merka's guide to what developers should expect from MEP services.

On site, quality control protects the design intent. Every fixture delivered is checked against the approved flow rate, pipe materials and jointing are inspected, and pressure tests are witnessed before walls and ceilings close. Merka's construction-stage inspection and testing covers those checks through to handover.

Commissioning closes the process. Potable systems are flushed and disinfected, non-potable systems are tested for cross-connections with dye or tracer tests, pumps and pressure-reducing valves are set to design values, and every meter is verified and connected to the building management system. The records from those tests become the operator's baseline for tracking consumption over the building's life.

If you have a residential, commercial or mixed-use project to design or build, MERKA's engineers and architects are ready to support you from the first concept through to handover. Our team brings structural, MEP and architectural design together under one roof, with water efficiency, drainage and green building requirements built into the design from the start.

Get in touch with our team to discuss your project, and we will guide you through the next steps.

Frequently Asked Questions

What is the most effective way to cut water use in a new UAE building? Start with demand reduction. Low-flow fixtures, controlled pressure and metering deliver the largest and most reliable savings, and they reduce the size of every downstream system.

Can air-conditioning condensate be reused? Yes. Condensate from air handling and fan coil units is low in dissolved solids and suits irrigation and cooling tower make-up with modest treatment. Volumes are highest in humid months, which matches peak irrigation demand.

Is greywater recycling allowed inside buildings in Dubai? Yes, subject to additional regulatory requirements for treatment, separate pipework, labelling and monitoring. The decision should be made at schematic design stage.

What is TSE and how is it used on building projects? Treated sewage effluent is wastewater treated at municipal plants to a standard suitable for non-potable uses. On building projects it is mainly used for landscape irrigation and, in some districts, for cooling.

Why does groundwater matter for water engineering? High water tables on coastal and low-lying plots affect excavation, basement waterproofing, uplift and concrete durability, so groundwater conditions shape both the structural and drainage design.

When should water strategy be decided on a project? At concept and schematic design. Tank locations, riser sizes, dual pipe networks, landscape zoning and drainage routes all depend on early decisions that are costly to change later.