Overseas community service (OCS)/ Youth expedition project (YEP) part 3: Are there still more things to check if my water is safe?

This post follows from 2 previous posts.

1. Overseas community service (OCS)/ Youth expedition project (YEP) part 1: Is that water safe?
2. Overseas community service (OCS)/ Youth expedition project (YEP) part 2: How do I know if that water is safe?

So you have checked out your watershed and everything looks ok. No industries, agriculture or villages around. Are we home and dry?

NO! We have not checked out the history or to be more exact, the geographical history of the watershed! Find out what the area used to be...

2. Historical geography

Example 1: Mining
Mining (granite, coal, metals etc.) can especially be nasty to health and environment even after closing down for years. Digging deep into the earth can release toxic substances (lead, radiological compounds, heavy metals etc.) found underground into water once the mine fills up with water after closure. Not surprisingly, mining can also impact groundwater quality so those looking at using well water do take note as well.


Or sometimes, the mining operation itself left hazardous waste which remains uncleared after closure.

Google "toxic legacy of mining" and you can find tonnes of examples. Here are a couple.

1. http://www.abc.net.au/rural/news/content/201102/s3142796.htm
   Australia - copper and gold mining can create a leachate with hazardous levels of copper, manganese and zinc.
2. http://keeptheban.org/?p=678
   France - uranium mining - "accumulation of radioactive metals in sediments and plants of rivers, ponds, and lakes by contamination around former mine sites has also been found to have high enough contamination to be considered “radioactive waste”"

And a common example is acid mine drainage in which sulfide ore from underground turns into sulfuric acid upon reaching the ground surface (chemistry is involved). This can be quite serious as it can turn water very acidic - pH of 1 or less.

Example 2: Agriculture
Depending on the type of agriculture, you can find different pollutants in the soil or sediment. And these pollutants may subsequently leach into the adjacent water bodies. If the pollutant load in the soil/sediment is heavy, the leaching can occur over a long period of years. Short of dredging the entire load of sediment or bulldozing the whole lot of earth, the problem can only be treated symptomatically without eradicating it source. (See a potential case study in a previous post - How to get rid of your seemingly unstoppable pond algae at Sungei Buloh.)

If we are talking about crop land or plantations, there is a likelihood of pesticides and fertiliser residues in the soil/sediment. On the other hand, animal farms will likely introduce animal waste (which is also a source of nutrients) into the soil/sediment. Nutrients/fertilisers are especially good at promoting eutrophication in water bodies while pesticides can be toxic to the ecology and us.

Most of you probably knows that Sungei Buloh used to be house prawn and fish farms in its mangroves before being converted into the wetland reserve we know together. However, do you know that it used to house pig farms too? (Wetland forest of Sungei Buloh mangroves) Has all the pig waste been cleared from the area? If not, can this be a source of nutrients leaching from the soil/sediment into the current mangrove area and causing eutrophication?



Example 3: Estuaries
In simple terms, an estuary is the intersection between a river and the sea. It can be in the form of a swamp, bay, delta etc. Not only does it accumulate (depending on the tidal and hydrological conditions) stuff from the river (think about oil, pesticides, heavy metals), it can also receive pollutants from shipping (ballast, waste, cargo overboard), especially along a busy shipping channel or near a port.

The port and upstream factories may not be there anymore but the pollants remaint in the sediment, possibly for a long time of decades and slowly releasing its toxic load of heavy metals and persistent organics (including dioxins, PCBs (polychlorinated biphenyls), -cides (pesticides, insecticides, herbicides)). BUT if someone decides to dredge the sediment (perhaps to keep the channel deep for shipping), you may see the serious problem of a massive dosing of pollutants into the water. Morale of the story: don't disturb the sediment unless you intend to remove the whole chunk as a long term solution.

Incidentally, heavy metals or persistent organics can show up in bottom feeders such as shellfish (mussels, clams etc.). They accumulate the substances as they wade through the sediments for food. Of course, what this means is they are potential bioindicators - indicating the health of the environment without doing a chemical analysis first.

The other more serious implication is if the locals feed on these bottom feeders, they may very well be intoxicating themselves.

Figure: 1969 topo map of the area around Ngee Ann Stream. Notice that the old railway track splits into 2 lines near the Bukit Timah station. Old maps are a good source of information on the geographical history of the area. Another source is old aerial photographs.

Figure: Google Earth view of the same Ngee Ann Stream (imagery data 2009, 2010). Some roads and waterways remain after all these years.

Figure: Photograph from The Straits Times, depicting the floods in 1978 and men rescuing their pigs. More importantly, it tells you that Woodlands, Braddell Road, Potong Pasir to Changi used to be a "farm belt". Such old news are another source of information.

Figure: Quarry lake on Pulau Ubin. Disused after the granite quarry has closed. How does such a mining activity affect the water quality?

Question about Lorong Halus

Hello Chen Ko

My name is B and I came across your blog (http://waterqualityinsingapore.blogspot.sg/2011/04/latest-wetland-craze-lorong-halus.html) while trying to find out more about the health risks of running in the possibly leachate-containing mud trails near Lorong Halus landfill (I browsed your blog and I realise this might not be your area of expertise but I would appreciate any insight at all :-) ).


I live near to Sungei Serangoon and have recently started running at and exploring the area around Lorong Halus (it's an awesomely beautiful area with lots of wildlife - and I share your love of nature and I'm also concerned about how successful these new wetlands will be - the undeveloped east bank carries so much more biodiversity than the developed west bank which is Punggol Promenade and HDB flats).

On several trips recently I've been exploring the dirt trails that run along the east bank of Sungei Serangoon, and up and down one tributary just south of Lorong Halus Wetland (it leads up to Lorong Halus near the TPE entrance), and I've been running across what looks like leachate, especially near the green pumping stations:

1. Most commonly orange-ish puddles/mud similar to these:

http://www.soilenvironmentservices.co.uk/images/projects/7_landfill_leachate_metal_contamination.jpg

http://www.wolfenotes.com/2010/06/dep-calls-toxic-landfill-leachate-natural/

2. Oily rainbow sheen on puddles/mud

3. (least common) Black fluid leaching into some puddles

There's no way to avoid these so I've been getting my feet into them, and though I don't really intend to return to those trails in future, I was concerned about how toxic these are, and I was wondering if you have any idea? (I've done some googling and found that (as per your blog as well) the common hazards are heavy metals and toxic organics - PCBs and dioxins?) These areas are not open to the public currently, but there are trails used by foreign workers who fish there (probably from the dorm at Tampines Road near Old Tampines Road).

Here's thanks in advance for any advice you can provide. :-)

Best regards and happy trails!

B


Hello B,

First off, here is a quote for the purpose of Lorong Halus Wetland. "Using an innovative bio-remediation system, national water agency PUB designed the Lorong Halus Wetland to collect and treat water passing through the former landfill, preventing it from flowing into Serangoon Reservoir." (1, 2)

My stance is I would not say that leachate is escaping from the landfill without rock solid proof.

Unfortunately, environmental forensics is often a complicated and expensive activity. Imagine gathering numerous soil, water and solid waste samples from many locations and testing them using sensitive AND expensive equipment in the lab. When the data come out, you still have to interpret them to build up a useful case. One method is to obtain a chemical "fingerprint" of the liquid oozing out of the earth to match that of the solid waste in the landfill. Perhaps the solid waste has a very specific pattern of chemicals (this gives you the "fingerprint") not found anywhere else in the surroundings. If you can positively detect the same patternin your liquid, voila! Then you may have a case.

But we are talking about the environment here. Many physical, chemical and biological processes (both human and natural) are occuring at the same time and these can alter your "nice" pattern of chemicals in unpredictable ways.

Or perhaps you can't find any usable "fingerprint". All is not lost. Another method involves injecting a tracer chemical into your landfill and see if it ends up somewhere else in the surroundings. Obviously, this tracer should not already be in the environment and should be easily detected. A good tracer can be radioactive for ease of detection though it may not be so friendly to the ecology. Some applications have used your familiar salt as a tracer so if your streams suddenly turns salty, you know where it comes from. Same thing here - your ecology may not like such an influx of salt much.
Even if you can afford the time and money, at the end of the day, your tonnes of data may still be inconclusive to prove that leachate is indeed escaping from a landfill. I guess this is quite similar to criminal forensics in which your evidence is based on probabilities e.g. 95% confidence level. What is not to say that the heavy metals and toxic organics in your puddle could have come from the metal processing plant a kilometre away?
In response to your observations:

1. "Orange-ish puddles/mud" are often caused by the presence of iron. Iron from soil (especially in Singapore soils) leaches out to the surface and form precipitates (orange solids similar to rust). This process can be facilitated by iron bacteria which "eat" (the chemical term is "oxidise") the iron for energy. Iron bacteria is easily identified by a orange/brown gelatinous slime.
2. "Oily rainbow sheen" can indeed be due to oil, especially if there is iridiscence. But it can also be caused by iron/manganese particles from the soil. A simple way to find out is to use a stick to disturb the sheen. If the sheen breaks up into pieces, it is probably iron/manganese. If the sheen swirls around and follows your stick, it is probably oil. Even if it is oil, it can be from natural sources e.g. plants, dead animals.
3. "Black fluid leaching into some puddles" can also be from nature. Is your fluid thick and viscous like engine oil? Or is it more like tea - black/brown yet clear? Tea coloured water can simply be tannins from decaying vegetation or humic substances (also originates from vegetation) from soil.

In essence, smoking gun evidence or even probable cause is hard to come by without further investigation and chemical testing. But if you ever find mass or sudden kill of plants or animals in the area, that is certainly a cause for concern though leachate may still not be the culprit.

Figure: Iron bacteria in a stream in Chinese Garden (Apr 2011). It can be a big aesthetic problem.

Figure: Iron bacteria in a small tributary at Ngee Ann Stream (Feb 2008). Even the vegetation were coated brown.

Figure: No, this is not sand. More iron bacteria on the canal bed at Ngee Ann Stream (Feb 2008)

Figure: Oil sheen on canal bed at Ngee Ann Stream (Feb 2008). Notice the iridiscence in the sheen.

Water quality monitoring workshop for CUGE (Centre for urban greenery and ecology) 2012

I just had another round of running the water quality monitoring workshop for CUGE (Centre for urban greenery and ecology). Attended by mostly Nparks staff and some staff from private companies, it was great fun to run this workshop. I suppose doing something you like is always fun, despite the sweat poured into its preparation (think logistics e.g. are you sure you have brought the right gear in enough quantities to run your course?) and the actual execution.

The workshop was run pretty similar to the one last year.

One notable exception was the use of iPads as data collection devices in the field. Water quality (WQ) data was keyed in directly into the iPad, forgoing the step of writing on pieces of paper that tend to get wet, muddy and folded out of shape. (Hey, with a seven hundred dollar iPad in your hands, you too would take tender, loving care of it.) Despite what you may think, I am not using it for the WOW factor or because it is the IN thing.

The main advantage of using an iPad is having a customised app (kindly designed by my colleague in SP's education department) to transmit the water quality data to a central server. One, all WQ data can be kept in one spot for easy reference in the future. Two, having a standard template (as an app) allows different users to key in data in a fixed format - no need to struggle to interpret whether this test was done once or twice or what the units were supposed to be. Imagine letting loose a group of students (or interns) to do WQM (water quality monitoring) in the field with only simple training and minimal supervision. Data collection will become immensely efficient. (Nevertheless, I must emphasise that these students be trained in the proper monitoring and sampling techniques lest they collect irrelevant or unusable data.)

Figure 1: The compulsory group photo taken at Graffiti Bridge along Ngee Ann Stream

Figure 2: The seldom taken group photo at the end of the workshop at Botanic Gardens

Figure 3: iPad app for water quality monitoring data collection

Figure 4: Screenshot from the server showing the WQ data since the system was started

Overseas community service (OCS)/ Youth expedition project (YEP) part 1: Is that water safe?

Our students are really lucky these days to have many opportunities to go overseas. We have acronyms like YEP (youth expedition project) (funded by MCYS), OCS (overseas community service), OCIP (overseas community immersion programme), OITP (overseas industrial training programme) plastered around campus, encouraging our students to sign up. In addition, we have more of the overseas outdoors variety of activities e.g. leadership camp, adventurers camp, mountain climbing, too.

Especially for YEP/OCS where the participants (students & staff) get to live close to the community they serve (read rural and undeveloped), they will stand next to the pond/stream/cistern/faucet/pail (take your pick) and ask, "Is that water safe?" Unfortunately, the answer may not be so straightforward.

Let's answer that question with another question, "Safe for what?"

For the brevity of this post and the significance of the intended use, let's restrict ourselves to "safe for drinking".

Water quality (WQ) parameters
If you are going to test the water according to WHO drinking water guidelines (more about the testing of water in an earlier post), you are going to find yourself wading in deep cess. You have close to 200 WQ parameters to test and the a complete set of tests will burn a big hole in your pocket. Fortunately, I can share some tips here to make your judgement easier or at least drastically reduce the kind of tests you need to make.

Sources of water

1. Rainwater
   This is the cleanest form of natural water. The processes of evapotranspiration and condensation in the water cycle is effectively a form of distillation. The only concerns will be air pollutants (e.g. acid gases, particulates). Acid gases will of course make the water acidic while particulates may contain heavy metals that go into rain. But the effects are likely to be small compared to the potential problems encountered in the next few sources. Hence, I would still put my bet on rainwater as a viable drinking water source among the various natural sources. This is also why I strongly advocate rainwater harvesting in communities that lack a reliable and safe source of drinking water.
2. Surface water: Pond, stream, lake
   I would check (ask the locals, check the map etc.) the upstream and the surroundings. Are there residences, industries, agriculture or other human activities? These can release human waste, animal waste, industrial waste, pesticides and other nasty stuff. Unless near the headwaters (usually thick jungles in the tropics), surface water tends to be turbid and contains an unhealthy does of bacteria. These are 2 good WQ parameters to measure if you still want to use surface water (perhaps combining with some sort of treatment). And if there are industries and agriculture around or upstream, you can add heavy metals, pesticides, oil, detergents, fertilisers into your to-do list of WQ testing.
   
   (Digression: Incidentally, I have seen outdoor activities being conducted with the participants immersed in a river (i.e. primary contact) in other countries. Hopefully, the organisers have bothered to check what is upstream of that river in case the participants gulp down mouthfuls of river water containing human waste from the village upstream.)
3. Groundwater: well, spring
   Generally less turbid and has less harmful bacteria than surface water. However, it may contain heavy metals (e.g. lead) that occur naturally in the ground. Depending on presence of arsenic deposits in your area (developed countries e.g. USA are not spared either), your groundwater may contain a dangerous concentration of arsenic.
   
   On the other hand, the presence of human activities e.g. industries can also lead to leaching of toxic chemicals (think organic solvents, pesticides, electroplating wash) into groundwater. This is especially true if the industry does not have a habit of cleaning up their act e.g. dumping waste into the ground like nobody's business instead of treating or sending it for proper disposal.
4. Man-made outlet: faucet, cistern
   
   Hey, the water must come from somewhere right? Is rainwater harvested and stored in the cistern? Or is there a pipe that conveys the water pumped from a well or stream? Maybe the nearby spring is diverted to come out from the faucet?
   
   Make the effort to find out the origins of your water and see if they come from any of the above 3 sources.
   
   Finally, your community/village may be lucky enough to have piped water from a water treatment plant! This may or may not be good news though. For one thing, it is hard to tell if the water treatment plant is doing a good job without doing any actual WQ testing. The locals may be able to advise you but then again, their bodies may have adapted to the water (clean or otherwise) and some effects do not appear in the short term.
   
   Note that not all water treatment plants are built alike or at least they are not built like our PUB plants which are considered effective and produce water of adequate drinking standard. I have heard of water treatment plants in other countries that add massive doses of chlorine to kill the germs but do little else to clean up their water. Well yes, you have germ free water but that heavy dose of chlorine will probably give you cancer years down the road.

I will continue in more future posts on this topic

Figure 1: Sand filter at our local water treatment plant at Chestnut Drive (see previous post).



Figure 2: Binjai Stream - this part is close to the headwaters so the water is relatively clean and clear, flowing over a sandy bed.



Figure 3: Ngee Ann Stream - this is further downstream from the headwaters. Note the obvious turbidity.

Water quality monitoring workshop for CUGE

I had the opportunity to conduct an inaugural water quality monitoring (WQM) workshop for CUGE (Centre for urban greenery and ecology). The participants were mostly Nparks staff. Before this, I had only worked with MOE teachers and students in my WQM courses.


It was indeed an eye opener. With their outdoor experience, my field trip became a non-issue. No complaints about the mozzies, the mud or the weather.

In fact, I dare say this field trip to Ngee Ann Stream was my most challenging. A huge tree has fallen over the path I normally took my participants. There was no clear path through it or around it. Fortunately, a hardy participant (L) came forward to blaze a trail through the fallen tree while I was wondering whether the rest were able to handle such bashing through. Reminding myself these were Nparks staff, everyone came through without a scratch despite the big ants scrambling all over the branches in protest of our intrusion. A few other “garang” types helped to clear the trail as L and I took the lead in our trailblazing.

Because of the wet weather earlier in the day, the canal was flooded. Usually a convenient way to cover ground, the canal became out of bounds. Since these guys and ladies were as good as I thought they were, I decided to do another round of bashing through a patch of tall grasses. Since these were only grasses (not trees or shrubs), I used my handy walking stick to sweep the blockage aside. Problem solved.

Though most of the participants have no chemistry background, they were thrilled with trying out the water testing kits back in our classroom. Designed for field work and hence simple to operate, most participants took an instant familiarity with the kits’ usage. In fact, they were more than enthusiastic to stay after 5p.m. to finish their water testing with the kits. It is always a pleasure to observe students with a passion to learn and experiment.

Figure: My favourite monitoring station along Ngee Ann Stream. A good shady spot for the participants to rest after the "gruelling" hike through tall grasses and steep slopes. Notice the tall grasses in middle - we had to bash through those after this station.

Figure: This canal is normally dry with only a small flow in the centre. On this day, an earlier rain has made the canal impassable. Even the participant has to collect a water sample on the steps. Not for school students.

Figure: Using water testing kits back in the classroom

Figure: Participants putting up their water quality data for all to see and compare.

Figure: Bug hunting and identification at Chinese Garden

Figure: We had the rare chance of checking out what Chinese Garden has implemented its admirable efforts to go green. This is a phytoremediation project to treat and reuse grey water from a toilet's sinks.


Update: Here is the link for a write-up of the workshop on CUGE' website
http://www.cuge.com.sg/October-2011 > 04 Oct 2011 - A Fun and Enriching Hands-on Experience Sampling and Testing Water

Outdoors classroom - Ngee Ann Stream

It is good to be back at Ngee Ann Stream where my water quality monitoring (WQM) workshop first started. Since then, I have brought groups on field trips to many other locales but none as charming as Ngee Ann Stream - so close to civilisation yet retaining the rustic and rural character of a lost world unknown to most Singaporeans. Despite losing some of its charm to development, I have never found another field location quite like it - a combination of different freshwater habitats, chest high Buffalo Grass to bash through, water seeping in through your shoes from the soggy soils, balancing yourself on narrow ledges, climbing down algae infested steps which are really part of a drain... the list goes on. (In KCK's list, Binjai Stream is in a close fight with Ngee Ann Stream for the most interesting waterway in Singapore but Binjai is more back to nature whereas Ngee Ann is more back to kampung so their charms are rather dichotomous.)

This time round, I have the pleasure of bringing students from River Valley High to my favourite outdoors classroom. The highlight of the trip must be the sudden heavy downpour near the end, accompanied by thunderous light show, courtesy of Mother Nature. Before this, many days have passed without rain - not a good sign as this means rain and thunderstorms become more probable with each passing day. (I know, this sounds like pseudoscience but it really works!)

Being in a canal when a big storm comes is a downright lousy place to be in - open terrain with no safe shelter and subject to flash floods which is such a trendy topic in Singapore nowadays. Being young (in age, if not, at heart) and energetic, we scurried back to the safe and dry confines of our transport in one piece. In case anyone thinks that such weather makes field trips a big no-no, nothing could be more wrong. We are living in Singapore, a country in the tropics - heavy rainfall is normal, thunderstorms are normal while shivering in an air-conditioned room all day is NOT normal nor healthy. We should not be baby-proofing nature (phrase is taken from Ice Age 3) for our youth. Given our current rate of development, I hope I won't ever see Singapore entombed in a climate controlled (aka air-conditioned) dome with nature only found in manicured parks and the only waterways are covered or canalised ones.

Ok, rant mode off... here are some pics for sharing.

Figure: Our field trip itinerary includes crossing the currently operational railway track. I always wonder what would happen to this beautiful patch of railway land when it is returned to Singapore. Will Ngee Ann Stream be further developed?

Figure: WQM in the canal. Most people don't get to climb into these canals throughout their lives.

Figure: In my opinion, the best photo of the day. Heavy downpour, wet staff and students, umbrellas out if available, a sense of urgency to scramble out from the canal - something real-life, capturing the moment and not posed

Figure: Posed photo - using a colour comparator to measure the ammonia content in the water back in the indoors classroom



A quick update for the past months

I would like to convince myself (and you) that my packed work schedule has prevented me from posting anything since the end of May. I know it is a shame but I am also sure that inertia has played a large part - not having posted for so long propagates the said behaviour :-)

In part to prove that I am really "busy" and to update you on the past activities, here is a summary of my "work".

June - July
Conducted "Freshwater quality and biodiversity" course for Crescent Girls, Henderson Sec Sch, Clementi Woods SS, Queensway SS. It was back to a tributary (sort of a naturalised drain) of Sg Ulu Pandan for more water quality testing and bug hunting.

Figure: The group hunt (for bugs)

Figure: Don't forget the water quality parameters

Figure: Sorting out the spoils of the hunt

Figure: A rare find - freshwater eel - too small for unagi though

Figure: The common Dragonfly nymphs though perhaps not so commonly seen by the students

Conducted a round of 6-day intensive AEM (advanced elective module) "Water quality and pollution".

Figure: On first sight, nothing wrong with the scene. But if you look closely enough, lots of people are looking down on their pants and shoes. This is what happens when you venture out in the wilderness in the rain and through knee high vegetation. All manner of creepy-crawlies are out their homes, latching on to the hapless passer-by (i.e. us).

Figure: Part of Ngee Ann Stream. Looks like another canal except that this used to be a natural stream with thick secondary forest on both edges. See next figure.

Figure: The same part of Ngee Ann Stream as the figure above but a year back. Note the vegetation stretching right to the edge of the secondary forest stream

Figure: An unusual find - a catfish struggling against the current in the "canalised" Ngee Ann Stream. Why was it doing so? I have no idea. Perhaps it should have just flowed along with the tide of change as what the rest of the stream did when it gave way to "development".

Figure: Due to the earlier heavy rain (what else is new in Singapore?), the whole canal was flooded, preventing the students from sampling the water (too dangerous).

Figure: The same part of the canal as the figure above but in drier times and more than a year back.

Figure: I simply can't resist putting in this routine group photo. Must show that the participants are in good spirits, right?

Singapore International Water Festival (27 Jun 2010)

Once again, I was roped in to organise the event "Amazing Greenviron Challenge" - an environmental quiz of sorts with indoor and outdoor components at the Marina Barrage. Weather was terrible in the morning so the outdoor part has to be moved indoors. (Right, rain was indeed heavy in June, giving rise to the shocking floods in downtown Singapore.)

Figure: Only 1 photo to show you here - the super group photo with organisers, student helpers and participants.

(Are we not done with the summary yet??? Afraid not... Did I mention that I had a tight schedule then?)

Water Quality Monitoring (WQM) (19 Jun 2010)

Amidst the tight schedule, I managed to sneak in a round of WQM with Team Seagrass at Chek Jawa.

Figure: On this rare sunny June morning, my students prepared their equipment for WQM.

To top it off, I attended the 4-day Wilderness Medical First Responder (WMFR) Course by OBS (Outward Bound Singapore) on Pulau Ubin. More on this in a later post.

Figure: WMFR participants and our dummies

WQM at Pasir Ris

Ah yes, the problematic kid on the block with regards to water quality - Pasir Ris Beach. (The latest advisory on its "fair" water quality is found here.) We checked out this notorious locale on this rainy July morning. Perhaps unknown to most people, this stretch of sand hosts 2 significant patches of seagrasses even though they are not monitored by Team Seagrass. (Some of the Team's members do however check out the seagrasses here in their own capacity.) And since there are seagrasses here, my team will of course be interested in the WQ.

Figure: 1 patch of seagrasses near Sg Loyang

Figure: The 2nd patch of seagrasses near Sg Tampines. I was told that there is a smaller patch further west near the end of Pasir Ris Park. We did not check this one out though.

Back to Ngee Ann Stream with Fairfield Methodist School (15 Mar 10)

This particular field trip for my advanced elective module (AEM), water quality and pollution, was reported in the Straits Times (25 Mar 10).

I have decided to post some exclusive footage not captured in the news article. (Actually, these are just routine photos I take every time I head to the field.) In addition, I have included a Google Earth file compiling all the water quality data gathered by the students on that hot and sunny morning. The students were given hands-on practice on the use of Google Earth as a means of documenting water quality data.

Figure: The 4 sampling stations displayed in Google Earth. Notice the ugly patch of cleared land. More land has since been cleared as Google Earth satellite photos are back dated. See previous post.

Aside to FMSS students in selected groups: Please use the compiled data in the Google Earth file to prepare for your case study presentation.

Figure: Group work at sampling station 2.

• The humble umbrella is immensely useful for field work as it can shield one from the rain and sun. (Try recording your data on a rain soaked piece of paper and you will know what I mean.)
• The other point to note is the highly turbid (muddy) water caused by sediments being washed down the canal from the nearby construction site. In fact, the turbidity exceeds 1000NTU which is the measurement limit of our turbidimeter (you may check the data here). This has never been observed before in this stretch of water.

Figure: Construction site - clearing of the secondary forest in progress. Note the open ground of easily eroded soil

Figure: Moving on from station 2. The canal floor was still wet from the drizzle earlier in the morning.

Figure: The customary group photo at "Graffiti Bridge" (sampling station 3). Many happy faces despite the "bedraggled" appearance