Checking out the water quality at Singapore's iconic (but mostly forgotten) landmark: Chinese Garden

Some time ago, I was lamenting about the lack of water bodies in Singapore for educational activities. I now realise that I have missed out a wonderful outdoors location for my water quality studies and it is none other than our iconic Chinese Garden. (The nearby Japanese Garden and Jurong Lake Park should also fit the bill as outdoors classrooms though I have yet to check them out.) When I was younger (decades ago?), Chinese Garden was always in the spotlight for shooting of period drama serials by the then SBC (Singapore Broadcasting Corporation) (now Mediacorp). Nowadays, it is mostly forgotten except for a handful of joggers, photographers and tourists. The latest attractions in town are the sexy casino and theme park on Sentosa, as well as the panoramic sky garden and another casino at Marina Bay Sands.Chinese Garden is so "history".

What prompted me to check out Chinese Garden was a friendly meeting with the management of the Garden under JTC (Jurong Town Corporation). They are really supportive of promoting the 2 gardens and 1 park for educational purposes - outdoors lessons, water quality studies, even relevant R&D. Do approach them if you think that they fit your educational curriculum as I am sure they will oblige your request.

Enough chatter. Here are some of the findings on my trip there.

Figure: A rather commonly encountered aesthetic problem is the obvious presence of algae in a few streams and ponds. We didn't try doing any sampling for fear of allergic reactions to algae and their metabolic products.

Figure: Quite a few healthy patches of cattails. We tried sampling for bugs (macroinvertebrates) here as such densely vegetated areas are their favourite haunt.

Figure: A small water body at the dead end of a stream. Because of the lack of flow and circulation, the end of this pond is occasionally overwhelmed by suspended sediments. We also did a sampling of the bugs here.

Figure: Sorting out the bugs from our water sampling. Surprise, surprise... there are healthy populations of various bugs despite the aesthetic problems mentioned above. Lots of shrimps, damselflies, some dragonflies, quite a few mayflies, water bugs, almost no worms and no leeches. The water is biologically (and implicitly chemically and physically) healthier than most water bodies I have sampled in Singapore. Make no mistake, Chinese Garden is THE place to visit for water quality work.

Some random thoughts on floods and water quality

I have been wanting to write something on floods and water quality since our Orchard Road floods make headline news in June 2010. But other committments in life came to the fore and this task became relegated to the background.

Brisbane floods: Up close (18 Jan 2011, ABC News)

Figure 1: This looks like some sort of water treatment or wastewater treatment plant in an industrial area

Figure: Same area as Figure 1 after the flood. Notice that the treatment plant is overwhelmed. If it is a water treatment plant supplying tap water, you can expect contaminants from the flood to go into tap water. If it is a wastewater treatment plant, you can expect untreated or partially treated wastewater to be carried by the flood to who knows where. Depending on the type of wastewater, contaminants can include raw sewage, industrial effluent (heavy metals, solvents etc.) or agricultural waste (animal waste, pesticides, fertilisers etc.).

Orchard Road Floods Straits Times/ Stomp (June 2010)

Figures: The same principle applies here. We had a flood. Flood washed everything around Orchard Road in its path. Let me hazard a guess - "everything" should include motor oil/ fuel (from vehicles), rubbish (glass, paper, aluminium), animal waste (stray animals, rats), pesticides/ fertilisers (lawns, green spaces) and lots of sediment (notice the "kopi susu"-like flood water). Where do you think the flood water eventually end up? Orchard Road is part of the Marina Reservoir watershed so yes, the contaminants end up in our reservoir. Our water treatment plants are supposed to be very effective so most of these stuff should be removed before reaching our taps. Even if this were true, treatment costs will likely rise from an increase in wear and tear of the treatment units handling such a heavy and diverse load of contaminants.

Figure: Tsunami caused by earthquake in Japan (Mar 2011) (japantsunamipics.com). The same can be said of a tsunami. It can carry everything nasty land pollutant in its path far inland, impacting water supplies and wastewater processing. I remember first learning about this term "tsunami" in secondary school geography. It didn't strike a chord with me then. Perhaps there weren't that many tsunamis then. But nowadays, even children know about this term when everyone can see horrific images of death and destruction following its wake. It has also receive much publicity since the tragic Asian tsunami in Dec 2004.

A disaster may be split into 2 phases with respect to its damage. The 1st phase is the disaster itself. Energy from an earthquake or flood causes loss of life and property. This phase usually lasts a short while (though there are floods that take months to recede). The second phase comes in when the population starts to rebuild their lives. The economy is torn to pieces. Food, water and fuel become scarce. Ditto for daily necessities. If law enforcement is weak and the people desperate, social disorder ensues. Without clean water (and food) and proper sanitation, people start coming down with water borne diseases which may spread without check, especially when people are herded into cramped refugee camps. See my earlier post for a fuller discussion on the aftermath of a disaster.

Answering a simple question - what is water quality?

The closest things are usually the ones we miss seeing.

Having blogged for 3 years about water quality, it comes as no surprise (or does it?) that I have not talked more about what water quality is.

Let's try to define it. I am a fan of 1-sentence definitions so I shall do the same here. Water quality simply tells you whether the water is suitable for use. Simple enough? Unfortunately, real life often complicates things. For example, what use? For whom (or what)? What is meant by suitable? How to measure suitable? (There goes the 1-sentence rule...)

What use?
These come to mind - drinking, washing, bathing, cooking, swimming, recreation, industry (food & beverage, wafer fabrication, pharmaceutical, cooling water, boiler water...), agriculture (animals, crops...)... The uses of water seem endless and mind boggling. But it doesn't end here.

For whom (or what)?
Environmental science used to be human centric, focusing only on the applications for society and the effects on the human condition. With the rise of the environmental movement, care and concern for non-human entities are increasingly becoming the norm. (I must stress that humans are too part of the web of life so it makes sense to care for these non-human entities. Anything that goes wrong in the environment will ultimately comes back to impact us. Remember - everything is connected to everything else.)

Have you considered the poor fish living in the wild downstream of your wastewater treatment plant? How about that rare aquatic fern surviving precariously in an increasingly polluted river?

Environmental protection and conservation have now come into the picture. Water quality must be of an adequate standard for organisms (especially aquatic ones) to survive and thrive. As someone pointed out, good water quality is not enough to nourish the ecosystem, you need to adopt a holistic view and protect/conserve the rest of the ecosystem too.

But before we get too carried away, don't forget the mind boggling uses of water listed at the beginning. There are many perspectives to water quality. The key is to first define the use for that water. Drinking water will have rather different requirements compard to industrial and agricultural water. Water quality for human consumption can be quite different from that for a fish or frog.

Just as water quality is only one of the many components of conservation, conservation is too only one component of water quality. You may protest, "what has happened to the 'nature conservation' given in your blog profile?" Nothing has happened. I still believe in conserving nature. But realise that water quality is a big topic, encompassing many different viewpoints that sometimes do not fit in well with one another.

What is meant by suitable? How to measure suitable?
This could be a can of worms so I will try not to open it (at least not in this post). Suitability is described by the various water quality parameters (dissolved oxygen (DO), pH, turbidity, metal content, pesticide concentration and many many more). Obviously, the type of use will determine which parameters are important and the limiting values of those parameters. For example, low DO is not a big issue for human drinking except that the water may taste flat. Yet a low DO water can get a fish killed from asphyxiation. Another example - a zero coliform count is expected of drinking water yet a count of less than 200 per 100mL of water is considered all right for swimming.

"Suitability" can be a dodgy term. Yet, I believe that regardless of the inadequacies of water quality parameters and their limiting values, they at least give us a grasp on the elusive nature of water quality and hopefully allow us to work towards better ways of defining water quality.