Posting this here because someone asked in the comments on this upload how to make it.

That upload is cloned from the purple water that was introduced with the 1.13 patch. If you want to create more variations, you can either copy that (CFLR 0xB4F762C9-0x00000000-0x000000000001A6F3, MATD 0x01D0E75D-0x00000000-0xCE3629042C312249, both in deltabuild0) or use one of my packages as a basis.

• The actual colour is defined in the Material Definition (MATD), "Diffuse" field (Entry 0x0E) . This is R, G, B, ? on a 0 .. 1 scale; I'd assume the last one would be alpha but it doesn't seem to make a visual difference in my game (as far as I can see). I've used this site to do the conversion -- there are probably better ones (I found it a bit fiddly to use) but since I only needed three conversions I didn't make any comparisons.
  
  
• Field 0xB7836507 (Entry 0x05) also seems to be a colour definition of some sort, but I couldn't see any difference in my game no matter what I changed it to. Maybe people with different graphics cards or settings, or better eye sight, can.
  
  
• The two images in my packages are the thumbnail (small colourful texture) and the overlay (larger, transparent texture) -- that's the wave texture, the stuff that is orange in the Maxis purple water.
  
  
• These are all manual clones so if you want to make additional versions you can just renumber them. It's not a lot of IDs to change:
  
  
  • In CFLR > MaterialList and MATD, change the ID of the MATD
  • In CFLR > ThumbnailHash, change the ID of the thumbnail picture (also renumber the picture itself)
  • In CFLR and STBL, change the name and description hash (plus the actual name / description in STBL; price, colour tag(s), swatch colour and swatch grouping in CFLR)
  • In MATD, change the ID of the DiffuseMap (that is the wave overlay), and renumber the picture

Also renumber the actual CFLR, MATD, STBL -- make up something like "yourusername_poolwater_yellow" and generate a FNV64 hash from that (with high bit) -- e.g. in s4pe > Tools > FNV Hash. I used the same ID for everything but the thumbnail pic (I haven't checked whether I could have done that too, since it's a different group than the overlay) .. less stuff to copy+paste.

You should use s4pe 0.4.1 or later for this -- Maxis changed the tag format in 1.13 and the purple water is using the new format.