Pang Sua. A rather unfortunate name due to how close it sounded to a "bad" word in Hokkien, my research about the name told me that Pang Sua probably means "weighting sand" in Hokkien. It seems that in the past, sand transporting lorries which were suspected of carrying more than the stipulated limit were escorted over to this area for weight tests, and that gave it the name.
Anyway, about the cache. First thing to know: this multi-cache is over 7km long.
On foot, you will probably require around 3 hours from start to finish. I recommend bicycles. Also, the final location for the cache does not have streetlights, so unless you are very brave, you should start this cache earlier in the day, or split it into multiple days. And bring water. Lots of it.
We start this cache in the revamped Pang Sua Pond. Built in the 1990s, this stormwater collection pond, which collects rainwater runoff from the surrounding catchment and pumps the water to Upper Seletar Reservoir for treatment and storage, has undergone landscaping enhancements so residents in the area can take part in more recreational activities there. After reopening in 2017, Pang Sua Pond now features Singapore's second-largest man-made floating wetland after the Sengkang Floating Wetland in Punggol Reservoir. One of the highlights of the pond’s facelift is its new 480m boardwalk that’s suspended up to seven metres above the waters.
NEW: Only 5 out of the 7 waypoints are needed for the coordinates, just in case some of them are unavailable. See bottom of listing for details.
WP1: Performance Stage
N 1° 22.890' E 103° 45.952'
We begin at the posted coordinates, on the multi-purpose stage on the pond. Go to the railings and read the text on them.
Behind the red rectangle is a 2-digit number.
Let A be this 2-digit number.
WP2: Scenic Bridge
N 1° 22.936' E 103° 45.984'
We then move on to the wooden bridge over one of the canals supplying this pond with water. The bridge has stubs on the sides that look like this:
Let B be the number of stubs like that in the picture, on both side of the bridge (don't miss the ones in the bushes!).
(B is an even number)
WP3: Pond Gym
N 1° 22.976' E 103° 45.919'
The next WP is located outside the gym along the pond. Go onto its roof and look for the sign in the photo below. From this position you will get a good view at the entire pond too.
There is a word behind the blue rectangle.
To get the value of C, take the first letter of the word and convert it into a number (a = 1, b = 2, etc).
WP4: Rail Corridor Test Track
N 1° 22.691' E 103° 45.633'
Time to wave goodbye to Pang Sua Pond and head over the Rail Corridor Test Track nearby. This 400m-long "test track" is located on the Rail Corridor and its goal is to test out various surface materials to see which is the most suitable to make the future Rail Corridor trail safer and more resilient. There is one part that actually glows in the dark:
Of course, as stated earlier, I do not recommend doing this cache at night. I heard that the glow is overrated anyway. Your goal here is to find the distance marker in the photo below:
Behind the red rectangle is a 2-digit number.
Let D be this 2-digit number.
WP5: Pang Sua Bridge
N 1° 23.015' E 103° 45.369'
In the past there used to be an old deteriorated bridge here, and the canal forced citizens on either side to take a detour around when they needed to cross it. On 2019, with the cooperation of NParks, the PUB and the Land Transport Authority, the bridge was finally restored, improving accessiblity for the residents around the area.
On your current side of the canal, find the 2 electric boxes nearby and read the labels on them:
Behind the red rectangle is a 2-digit number.
Let E be this 2-digit number.
WP6: Yew Tee Flyover
N 1° 23.355' E 103° 45.108'
Time for a little "spelunking". This WP is located underneath the Yew Tee Flyover. You can find a toilet, water fountain, vending machine and benches here under the shade, a perfect resting point. Your mission here is to locate one of the plates depicted in the photo below under the flyover:
There is a word behind the blue rectangle.
To get the value of F, take the first letter of the word and convert it into a number (a = 1, b = 2, etc).
(The word has 8 letters)
WP7: Fishing Deck
N 1° 24.099' E 103° 45.140'
This little fishing and viewing deck is pretty popular with residents, joggers, and fishing enthusiasts. The railings are designed in a way that allow fishermen to stick their rods through and let them rest on the horizontal beams. Find the sign in the photo below (there are 2 identical ones):
Let G be the number of "windows" behind the red rectangles.
The Cache
N 1° 25.XXX' E 103° 44.YYY'
To get XXX, substract 225 from the first 3 digits of (A*B*C*D*E*F*G).
To get YYY, add 70 to the next 3 digits of (A*B*C*D*E*F*G).
The hint for the cache location is within the geochecker:
Alternate means of deriving the coordinates (in case one/two WP are unavailable):
1. Go to: https://asecuritysite.com/encryption/shamir_decode
2. Paste these into "Secret shares":
0{A}WAqzvhdvgvQaYPgkTGQO5N7/4BOjO0jVvWBjKg==
0{B}LLW8ek5InI+TGqKZfIcJS64vIXqssqBDJvdqGg==
0{C+5}RW5vL118gl3JkOMGxSrDckOkQ4FYHeMjAwUbeQ==
0{D}SV5EVgYi+1hohzKuv6uab/2tx5gnvd51pYCzpQ==
0{E}VYi4WMe3QL714hdx20QT98r2O6m4GrpVSco6ww==
0{F}gOOrskvu3VxD53cqcDvU1/ELy+GMSYhUMsZpoQ==
0{G}CC8MaxocMYTZODHj9hCSIW9XlLNc8ZH38JiGoQ==
4. Replace the letters in curly brackets with the solutions from the WPs and remove the curly brackets. Do any maths within the curly brackets. If the number only has 1 digit add a "0" before it.
For instance: if A = 1, replace "0{A}aX4fL8dlDRWiMb9ZQwx+l33q6MaFCmyl9566ig==" with "001aX4fL8dlDRWiMb9ZQwx+l33q6MaFCmyl9566ig==".
If E = 150, replace "0{E-100}TGat5cDFEnrzo/ziy4iBA/h3LfDj2yDM0RAgnQ==" with "050TGat5cDFEnrzo/ziy4iBA/h3LfDj2yDM0RAgnQ==".
5. Omit any lines with values you do not know. Only 5 lines are needed. Make sure there are no blank lines.
6. Press "Determine" and scroll to the bottom of "Reconstructed" for the coordinates!
Please use this only as a backup in case 1/2 of the WPs are unavailable!