Not quite sure whether you are a young student or an employee holding a very junior position since you don't know that all contracts reached or agreements signed can be renegotiated due to "imperfect contracts" or changed circumstances. Renegotiation of contracts and agreements are a fairly common practice the world over, both amongst commercial entities and between countries. As examples, the US' renegotiation with Japan over the already signed terms for the joint development of the FSX fighter jets in the 90s, the renegotiation over their secret agreement limiting the sale of supercomputers, Trump's current attempt to renegotiate trade deals (by simply withdrawing from them), the EU's plans to renegotiate with the US over air traffic rights, the EU's failed attempt (due to Portugal's veto) to renegotiate the co-operation pact between the EU and ASEAN (which ASEAN and Singapore welcomed), Sabah wanting to renegotiate the unfair terms of her accession to the Malaysian Federation, etc, etc, etc.
You have Singapore renegotiating pacts which enabled her to move from a "grey" list of countries considered lax in sharing tax information to a "white" list of nations conforming to international standards ("Mr Tharman said Singapore will continue to renegotiate similar deals, with more [pacts] expected to be signed by the end of the year..."Singapore in The White, 147 Prostitute Press, 14 November 2009 ) including Singapore's past plans to renegotiate this water agreement so long as it was renegotiated along with other issues as a "package".
There is no need for you to feel that you are being traitorous if you decide to use your brain and do your own research and study instead of blindly swallowing, in the name of patriotism, the half-truths, misleading information and rubbish that come out of the mouths of the Singapore government and its incompetent officials. If you continue to do so though, my advice to you is to invest in a personal ambulance.