Sunday, March 29, 2015

Enough clean water for my children and their children - remembering Mr Lee Kuan Yew (LKY)

This week (23 - 29 Mar 2015) marks the mourning of the passing of our first prime minister, Mr Lee Kuan Yew (LKY), widely recognised as Singapore's founding father.

As I was going through the historical documentaries of the man shown continuously on TV, I was reminded of his contributions to the water supply in Singapore. The early years of Singapore (1960s, 70s) were trying times. Massive issues had to be resolved right there and then - housing, education, healthcare, security, jobs and of course water and sanitation. It was mind boggling to contemplate these issues all together, much less come up with workable solutions.

Anyone familiar with human nature should realise that once the basic human needs (e.g. food, water, shelter) are not met or disrupted, you are going to have lots of trouble on your hands. Think about looting, rioting and general social unrest - just look at Chile, Haiti after earthquakes. I am sure there are many more such examples if you google them up.

No, in the chaotic situation that is Singapore in the 1960s, water needs must be effectively addressed. (Sanitation too as I believe water and sanitation are merely 2 sides of the same coin hence the term, watsan but sanitation is a story for another day.)


http://www.pub.gov.sg/water/memory_LKY/Pages/default.aspx:
'In 1963, just a few years after its self-governance was declared, Singapore experienced a severe drought. This harsh experience left a deep mark on the population. As the Prime Minister of Singapore at that time, Mr Lee Kuan Yew was determined to drive Singapore towards water sustainability. This, he did by making water a top priority in government policies. "This [water] dominated every other policy. Every other policy had to bend at the knees for water survival."'

In those early days, LKY already realised that there would not be enough water given the paces of development and population increase. Water from reservoirs and from Malaysia were not going to make it. (Only MacRitchie, Pierce, Seletar and Fort Canning (for the port) were operational as of 1963. Source: PUB) (As of the 1960s, the very first agreement signed in 1927 was no longer in force. 2 others - 1 signed in 1961, another one in 1962, were then operational. Source: Singapore Infopedia)

Looking at the scene now (2015), I am quite pleased to see the 4 National Taps operating - local catchment, imported water, Newater, desalted water. By 2060,
  • Total local catchment area will have increased from the current 2/3 to 90% of surface area (see previous post related to this topic)
  • http://www.pub.gov.sg/about/historyfuture/Pages/WaterSupply.aspx:
    "Currently, NEWater meets up to 30% of the nation’s current water needs. By 2060, we plan to triple the current NEWater capacity so that NEWater can meet up to 55% of our future water demand."
  • http://www.pub.gov.sg/about/historyfuture/Pages/WaterSupply.aspx:
    "Today, desalinated water can meet up to 25% of Singapore’s current water demand. The plan is to grow Singapore’s desalination capacity, so that the Fourth National Tap will be able to meet up to 25% of our future water demand by 2060."
  • What is so special about 2060?
    http://eresources.nlb.gov.sg/infopedia/articles/SIP_1533_2009-06-23.html:
    "Beyond 2061The Singapore government has stated that it will not renew the 1961 agreement which expires in 2011. Attempts to reach a new deal with Malaysia to secure water supply for Singapore beyond 2061 have not borne fruit despite years of tedious negotiations. To reduce Singapore's dependence on imported water, the government has taken steps to increase the size of the local water catchment area and to build up the supply from non-conventional sources, namely NEWater (reclaimed water) and desalinated water. With the various water projects progressing well, government officials have assured Singaporeans that the country can be self-reliant in water by 2061 if it needs to be."

    Yup, so that is it. The last 20% will be served by local catchment by 2060.
With such forward planning, I feel assured that the water needs of the country and my family will be well met...

But... (there's always a but) all these come at a price. Newater and desalted water are not cheap to produce. Requiring sophisticated reverse osmosis units using easily fouled membranes, they basically involve passing contaminated water through a filter that removes the contaminants. Imagine a filter with really small holes that only allow water molecules to go through. Even small stuff like salts and oils are retained on the filter. This is going to use lots of pressure to push the water through and  associated with it are high energy usage and costs.

https://www.cscollege.gov.sg/Knowledge/ethos/Issue%202%20Apr%202007/Pages/Water-Management-in-Singapore.aspx:
"The first year (2003) tender price for NEWater from Singapore's Ulu Pandan plant was S$0.30/m3, which is significantly less than the cost of desalinated water. The selling price of NEWater is S$1.15/m3, which covers production, transmission and distribution costs."

"The cost of the desalinated water during its first year (2005) of operation was S$0.78/cubic metres."

Desalted water is naturally more expensive to produce than Newater because seawater is much more saltier ("contaminated") than normal wastewater in our sewers. As such, you need much higher pressure (translated into energy and cost) to filter off the salt in seawater.

In contrast, the production cost of tap water should be in cents/m3 (sorry, can't find a good source for this figure. I picked it up when I studied about reverse osmosis in university.)  

Finally, don't forget that to ensure water security for our small nation, energy security is a co-requisite. Without natural gas, biofuel or whatever to generate electricity, desalination and Newater production will be adversely affected.

Thursday, March 26, 2015

The curse on the waters off Pasir Ris

The waters off Pasir Ris seem destined to be cursed with massive fish kills now and then. Fish kills have been documented there for years! (See my previous posts on this topic.) The latest came as no surprise - Straits Times 1, 2; Today 3, 4; Channel News Asia (CNA) 5.

In response to an invitation from CNA to check out the waters there, a team of us headed down to the field for a quick water quality monitoring (WQM). It had been a week since the fish kill occurred so I was not expecting to see anything extraordinary in our WQM results. Nevertheless, it was a good chance to stretch those hands and legs on some good old field work.

Other than conducting field trips for my students as part of their curriculum, it has been some time since I have field work in WQM. For those following my blog, I had been involved in other aspects of water the past few years - rainwater harvesting, grey water recycling. Water is such a fascinating yet vast topic. It can cover indoors, outdoors, natural, industrial, agricultural, household, economics, political, war and many other areas besides.

Back to Pasir Ris... On 10 Mar 2015, we did WQ tests at 2 spots at Pasir Ris and 1 spot at Punggol for reference. Here is a summary of the results.



The number above may appear intimidating but worry not, below is a description in plain English.


Overall, the water quality looked pretty good for all 3 locations. A few points:

1.       The water at Pasir Ris has become somewhat saltier compared to my data in 2010.

2.       The water has also become somewhat more alkaline compared to my data in 2010.

3.       The water is significantly clearer (less turbid) compared to 2010. Less construction work going on?

4.       Nutrients (ammonia, nitrate, phosphate) are significantly less compared to 2010.

5.       Bacterial counts are significantly less compared to 2010. Can we all swim there now?

6.       Pasir Ris spot 1 appeared to have a slightly higher bacterial count compared to the other 2 locations. FYI, spot 1 is where a great deal of dead fish were washed up the previous week.

 Don't forget, about a week has passed since the fish kill. Don't expect to see problems in the water quality during our field trip or we will still be seeing dead fish on the shores for the entire week - a scary thought.

Figure: WQM team at work at Pasir Ris

Figure: The cozy CNA van that brought us and our equipment around our test sites

Tuesday, March 17, 2015

Fluoride and other contaminants in beer


Hi there,

I've browsed your blog many occasions and always found it a good read, irregardless of whether it answered a question I had at that point in time. 

A bit of background - Water is something key to my interests, as I have grown up with freshwater fish and currently have become a brewer(of beer). Therefore chemistry and quality of the local liquor has always concerned me. 

I have recently installed a water filtration system at home with activated alumina - with the intention of removing fluoride. Would you have any advice on where I could get a water test done up? Key substances would be chlorine, chloramine and fluoride. Also, I'd be open if you have other advice to share.

Best regards,
E


Hi E,

Thanks for sharing your interests and your thoughts on my blog.

You have touched on one of those controversial and hotly debated health topics in water and food - fluoride. Fluoridation of drinking water was initially touted as beneficial to the protection of teeth against decay. Over the years, studies have shown that an excessive amount of fluoride in our bodies can lead to fluorosis which affects the teeth and bones adversely. The irony is not lost to most people aware of this issue - too little fluoride, you get tooth decay; too much, you get teeth damage.

More about fluorosis in this WHO (World Health Organisation) page or feel free to google up yourself:
"The dental effects of fluorosis develop much earlier than the skeletal effects in people exposed to large amounts of fluoride. Clinical dental fluorosis is characterized by staining and pitting of the teeth. In more severe cases all the enamel may be damaged.

Chronic high-level exposure to fluoride can lead to skeletal fluorosis. In skeletal fluorosis, fluoride accumulates in the bone progressively over many years. The early symptoms of skeletal fluorosis, include stiffness and pain in the joints. In severe cases, the bone structure may change and ligaments may calcify, with resulting impairment of muscles and pain."

Naturally, one BIG question is what constitutes an excessive amount. Remember, our intake of fluoride includes the food we eat too. There are already arguments against fluoridation of drinking water since it is claimed that the dosage from our food is already enough to fight tooth decay. According to the drinking water guidelines from WHO, the limit of fluoride stands at 1.5ppm (parts per million). And based on the Singapore Drinking Water Quality Report 2014 from  PUB, our drinking water has an average of 0.48ppm and a range of 0.40-0.62ppm fluoride.

For people concerned about fluoride, filters containing activated alumina have been well known to remove fluoride. Back to answering E's question, my concern is given the already low level of fluoride in Singapore tap water (see previous post, Evaluating the necessity and usefulness of water filters for domestic tap water for an idea), how effective is your filter in removing fluoride? I was going to ask whether there is a need to remove the already low levels of fluoride but since you have already installed the filter, this question is moot. :-)

If your intention to test for fluoride, chlorine and chloramine is one-off, then you can approach a commercial testing lab. The ones I know are (in no particular order):
  1. Tuv Sud PSB
  2. SGS Testing
  3. Setsco Services
  4. CPG Laboratories
If you only have one water sample to test, I believe your tests should not cost more than a hundred dollars. BUT very importantly, do find out the detection limits for their tests. If the test results show zero, they simply mean that that particular contaminant is NOT DETECTED rather than totally absent.

On the other hand, if you intend to conduct these water quality tests on a long term basis, you may want to consider getting a test kit such as the Checkit Comparator from Aqualytic. The Local distributor is Quantum Technologies Global Pte Ltd. It is designed to test for fluoride from 0.2-2ppm. I feel that this should be enough for your purpose. To detect any lower concentration will require more complicated (and expensive) instruments normally found in a lab. And frankly, I am sceptical that there is a need to reduce the fluoride concentration any lower for beer. Not to mention that it may not be economical to do so - you will need technology more advanced than filters to achieve that low a level.

Similarly, the Checkit Comparator can also test for chlorine (free chlorine ) and chloramines (combined chlorine). But do note that each of these tests require the use of different chemicals. Please be careful about storage, handling and disposal. Wear protective gear and make sure other people are not unnecessarily exposed, especially children.

Figure: Aqualytic Checkit Comparator. Different coloured discs are used for different tests. The above discs are for nitrate (pink), ammonia (green), phosphate (blue).