In Vanilla/PTW, industrious workers are twice as fast at completing tasks than other Civs. I think in C3C industrious workers are only 50% faster.
Thus irrigating in PTW is only 2 turns for industrious. It would be 3 turns for C3C. Mining is 3 turns in PTW, 4 turns in C3C.
I don't have C3C, so correct me if I am wrong on the comparison.