Government Sewerage System

Denpasar Sewerage Development Project or Bali's New Mains Sewerage System

Water purity and the sewage system

Sewerage systems keep the groundwater and tap water clean

Here in Bali we all know that if we get a dose of the galloping trots it is usually from the water. The reason is quite simple, an island littered with septic tanks, most of which were neither properly designed nor constructed, have probably cracked and all of which empty their semi processed waste into the ground to go who knows where, is bound to get somewhat contaminated. Water bores too close to septic tanks and leaking government water supply pipes mean that what comes out of our taps can be just a little untrustworthy at times.

A New Sewage System For Bali

But there is good news. The government of Bali has recognised this serious problem and, committed to cleaning up the island's contaminated water, has in recent years set about installing a government sewage disposal system to collect black water (from toilets) and grey water (from showers, washbasins, washing machines and kitchen sinks) and deliver it to a sewage treatment plant for processing and disposal.

The project is known as the Denpasar Sewerage Development Project or DSDP and is funded with the assistance of JICA (the Japan International Cooperation Agency). It is a long term project that started with a feasibility study in 1994 with work commencing in 2004. The major pipework systems for much of the major area of Denpasar, Kuta and Sanur along with pump stations and the sewage plant were completed in 2008. Since then an ongoing project has been underway to progressively connect up houses, restaurants, hotels and other premises to the system. Phase DSDP 1 is already completed with 7,000 connections made to the system. DSDP 2 is under way with a final target of 15,000 connections made, so far 12,665 connections have been completed.

The overall project for the whole of Bali is expected to connect over 36,000 subscribers, using 200 klms of pipes and is planned for completion in the 2030s.

The project is being managed by the Unit Pelaksana Teknis Pengelolaan Air Limbah or UPT PAL (Waste Water Technical Management Unit) and so far it covers three major areas.

Areas the system covers

The first, Denpasar, feeds effluent from all of Denpasar into a main sewer which runs down Jalan Sesetan to the traffic lights at Benoa and from here to the sewage plant which is situated in Suwung. For most of the system covering the Denpasar area the waste water simply flows under gravity while a small area in Western Denpasar requires a pump to pump the waste up to Jalan Sesetan.

The second area, Sanur, has two main north-south sewer pipes one running down under Jalan Bypass Ngurah Rai and a second running down under Jalan Tamblingan collecting waste water and carrying it to a main pump house situated next to the bypass at the South Western corner of Sanur. Three pumps with a total capacity of 12.4 cubic metres per minute pump the waste water through a main pipe along the bypass to Suwung.

The Third area covers an area from the airport up to the North end of Seminyak and includes Kuta, Legian and Seminyak with a main sewer running down Jalan Legian. There is a main pump house near Jalan Imam Bonjol with 3 pumps with a total capacity of 23.8 cubic metres a minute which pump the waste to Suwung. Much of the area covered by this system is below the level of Jalan Legian and a series of pumps is needed to push waste water from the various areas up to the main sewer line.

At Suwung there is a large sewage treatment plant that covers 10 hectares of land. Here 4 large holding ponds (2 aerated for bacterial breakdown of the waste water and 2 sedimentation ponds) can process up to 51,000 cubic metres of waster water per day.

The DSDP is an important system for improving health in Bali (to say nothing of the unrequested colonic evacuation that many of our visitors tend to undergo) and, for most of us, provides the opportunity to do away with those troublesome septic systems with their unmanaged septic discharges.

Operational problems caused by customers

Unfortunately the DSDP has four major issues which are making life difficult for them:

1. Their biggest problem is the disposal of sanitary napkins into toilets. Sanitary napkins easily block pipes and are not biodegradeable, they do not break down in the processing plant.
2. Grease (which includes fat and oils) from cooking particularly restaurants and hotels.
3. Rainwater. So called plumbers with brains like swiss cheeses take the easy way out and connect rain water drainage into the sewers because they are unable to come up with a more sensible solution.
4. Sand and earth from gardens and construction sites. I am aware of a recently built hotel that was driving DSDP nuts by discharging sand into the sewer and blocking it.

How we can help

Your help is needed and it would be a major benefit if you could take the following steps:

• Do not allow sanitary knapkins to be put into toilets
• Do not put cooking oils or fats into your drains.
• If you have a lot of cooking going on install a grease trap to collect grease.
• Do not lift sewer manholes to drain your flooded garden.
• Do not allow construction workers to dispose of their rubbish and waste down the drains and sewers.
• Make sure your rainwater drains are not connected to sewers.

How to get connected

Does the sewage system cover your area? Have a look around, if you see circular concrete manhole covers in the road near your property you can be fairly sure that the sewage system is available. The manhole covers have the letters DSDP cast into them.

• If you wish to be connected to the DSDP system the procedure is as follows:
• Go to the DSDP office and fill in a form.
• DSDP will send staff to survey your property.
• They will make sure a connection from your property to the main sewer is installed. On your property end they will install a connection box known as an HI or "House Inlet" box.
• You will then have to arrange for your own plumber to connect your property system to the House Inlet box.
• You will then have an account set up and you pay a monthly charge for the service.

Monthly Charges

Charges are as follows:

It is as simple as that. No more pumping full septic tanks, no more worrying about where the waste goes and you will be doing your bit to help clean up Bali.