I rate Water Monopoly a bit differently than Cpt_nice. The thing is, I don't see it getting scored early enough often enough for the effect to be great.
It's useful to consider the alternatives for a Jinteki deck with 3 advancement cost (* = will rotate out soon):
- Ancestral Imager - Damage when the runner jacks out. Decent in kill decks, mediocre otherwise.
- Braintrust* - When over-advanced cheapens rez of ice. A 3/2 with no downsides so great.
- Chronos Project - Remove all cards in the runner's heap from the game. Devastating against some decks, nearly useless against others.
- Dedicated Neural Net - Once scored gives you a 2/3 chance to make the runner not access agenda's from HQ. Decent to good.
- Encrypted Portals - Gives credits for code gates, boosts code gate strength. Decent.
- False Lead* - Can be forfeited to make the runner close a click. Useful in the right kill deck, though usually that will be HB.
- Genetic Resequencing - Put an agenda counter on a scored agenda. Meh.
- Gila Hands Arcology - Click for 1.5. Mediocre.
- House of Knives - Deal damage during a run, three times. Decent in general, great in the right deck.
- Merger - 3/2, but 3/3 for the runner and costs 1 influence. Not terribly great but good for fast advance.
- Philotic Entanglement - Deals damage and is a 3/2. Little reason not to include it, though only one copy per deck allowed.
- Profiteering* - Lets you take bad pub for credits. Not great.
- The Future is Now - Tutor for a single card. Always useful.
- Unorthodox Predictions - Effectively block the runner from accessing reasonably protected servers for a turn. Mediocre.
- Veterans Program* - Remove bad pub. Good if you expect bad pub.
At the very least Braintrust, Philotic Entanglement and The Future is Now are better. Chronos Project and House of Knives are probably better as well.
Given the competition and the not great chance of Water Monopoly firing early enough to make a large impact on the game I expect it to find a permanent home in the binder.