Sewerage

Sewerage and “sewage” are regularly used interchangeably, however actually incorrect. Sewage refers to the waste that is discharged, whereas, sewerage/ sewers are the structure that the discharge goes into.

Sewerage (or “sewer system”) is the infrastructure that conveys sewage or surface runoff (stormwater, meltwater, rainwater) using sewers.

Sewage and wastewater contain bacteria, fungi, parasites, and viruses that can cause infections in the intestine, lungs, and other organs.

Sewage is a type of wastewater that is produced by a community. It is typically transported through a sewer system. It consists of wastewater discharged from residences; commercial; institutional, and public facilities that exist in a locality.

Sub-types of sewage are, ‘greywater’ (from sinks, bathtubs, showers, dishwashers, and clothes washers) and ‘blackwater’ (the water used to flush toilets, combined with the human waste that it flushes away).

For instance, Dubai in the United Arab Emirates (UAE) was built before a sufficient sewer system was in place, thus, tankers were deployed to remove human waste from residential and commercial complexes.

During Dubai's economic boom in the 2000s, the city's growth was stretching the existing sewage treatment infrastructure to its limits.

Due to the difficulty of maintaining pipes in the shifting sands of the desert, sewage from areas of Dubai not connected to the municipal sewer system network at the time was collected daily from thousands of septic-tanks around the city and driven to the city's only sewage treatment plant at "Al-Aweer".

Because of the long queues and delays, many tanker drivers resorted to illegally dumping the raw sewage into storm drains or behind dunes in the desert, resulting in much controversy.

Sewage dumped into storm drains flowed directly into the Persian Gulf, near the city's prime swimming beaches. Doctors warned that tourists using the beaches ran the risk of contracting serious illnesses like typhoid and hepatitis.

A 2009 YouTube video that showed a conga-line of tankers taking human waste out of Dubai to a plant went viral. Subsequently, it is alleged that a news network reported that E. coli bacteria breakouts were happening in Dubai, even though it was “filthy rich,” because much of the city wasn’t connected to a sewer system.

In response, by 2011 the “Gulf Today” newspaper published that within a few years, the city’s sewer system had caught-up with the fast pace of Dubai's growth.

The two main Dubai municipal sewage treatment plants are Al Aweer and "Jebel Ali." There are also a few smaller facilities that are run by private companies.

The first phase of the Al Aweer plant was meant to handle 260,000 m3 of waste per day, but by December 2007, it was handling nearly 500,000 m3 per day. When the plant’s second phase went into operation, it was able to handle an extra 65,000 m3; and by its third phase, the plant would've added 80,000 m3 more to its capacity.

By easing pressure on the Al Aweer plant, the first two phases of the Jebel Ali plant were completed in April 2009 and begun operations. The second phase was completed in October 2010 treating some 300,000 m3.

Other like "Concorde-Corodex" has membrane bioreactor sewage treatment plants on both the Palm Jumeirah and in Dubai International City; while, "Metito" operates and maintains a 2,000 m3 per day sequencing batch reactor sewage treatment plant that treats sewage collected from the Sky Courts complex; whilst "Concordia" operates a sewage treatment plant serving "The Galleries" development in downtown Jebel Ali.

Dubai’s ambitious ‘Strategic Tunnel Enhancement Program’ (STEP) is building a brand-new sewer system with deep tunnels to be completed by 2025. The government news agency called the project the “Development of the Century” because it is expected to save millions of dirhams in upkeep costs and help Dubai reach its goal of becoming the most sustainable city in the world.

For the sewer system to work, two tubes are being built deep below the city making use of gravity for the collection of sewage, along with 140 km of sewers and key pumping units. The tubes will replace more than 121 existing sewer pumping stations, so tankers won’t have to move waste around the city anymore.

One will start in Bur Dubai and take waste to the Jebel Ali treatment plant. The other will start in Deira and take sewage to the "Al Warsan" treatment plant, which according to GlobalData is expected to enter into operation in 2023.

That said, there are a host of tall buildings in Dubai and many of them aren’t connected to a municipal sewer system. Among such, the tallest building in the world is the "Burj Khalifa" named in honor of the former President of the UAE's, Sheikh Khalifa bin Zayed Al Nahyan.?

A remarkable feat of engineering that was completed in only five years at a height of 828 meters (2,722 feet, or just over half a mile); with 163 floors, 57 elevators and 8 escalators; servicing more than 800 apartments; over 37 floors of offices; and a 15 floors (304-room) Hotel, having a combined possible occupancy of up-to 35,000 people at a time, where thousands of tourists come every day to climb the observation deck, all producing a staggering 15 tons of sewage per day.

According to “Fracttal”, an asset maintenance and management solution provider, the management has the not-so-pleasant task of having to dispose of the building’s waste, making use of a 1,300 m long waste chutes, with waste travelling down at around 194 km/h and compacted before being sent off.??

“DIP” Travel Portal, has it that, the highest tower in the world simply does not have a sewer system. Therefore, tankers are used daily: every day a whole bunch pulls-up to the shimmering tower for sewage disposal.

One might be wondering why someone would spend $1.5 billion on building a skyscraper without a waste disposal system?

DIP adds, the fact is that when the Burj was completed, Dubai recovering from the effects of the 2008 credit crunch, it was decided that the cost of adding it to the city’s already overburdened sewer system was a waste of money. The developers were sure that taking out their waste every day would be cheaper than upgrading the sewer system.

To this end, Dubai's municipality has approved a transformative centennial sewer plan that will serve the city population for the next 100 years, and has set a target of recycling 100 per cent of the Emirate's wastewater by 2030 as part of its sustainability strategy…

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Food for thought!