The Black Ferns are the undisputed queens of rugby, having dominated the women's game at the highest level for the last decade. They haven't lost a Test since 2001 and have won the last three World Cups in 1998, 2002 and 2006.
Lewis saw first hand earlier this week just how good the Kiwis are when he saw them destroy England A 48-3 at Esher in a prelude to their second Test against England on Saturday.
"New Zealand deserve to be seeded one," he said referring to the World Cup. "There isn't any question about that as they've set the benchmark for a number of years.
"It's a tough group but my point of view is that you would expect every group to be tough in a World Cup. But as a group, if we have any ambitions of making it all the way to the final, then you have to play against the best, and beat them, to get there.
"We very rarely play against teams like New Zealand, South Africa or Australia so that is a huge bonus for us. We are under no illusions as to what lies ahead but the girls have accepted the challenge and are willing to tackle it head on."
Lewis has an early opportunity to run the rule over his squad when they take on Sweden in an international at the Vale Resort on November 28. The World Cup may not be until August 2010, but the Welsh coach is already thinking of the bigger picture by giving hooker Becky Newton, fly-half Elinor Snowsill and winger Caryl James their international bows while another newcomer, backrower Lisa Newton, starts from the bench.
Wales vs Sweden (28th November 09)
1. Catrin Edwards (Cardiff Quins)
2. Becky Newton (Cardiff Quins)
3. Hannah Roberts (UWIC)
4. Gemma Hallett (Pontyclun)
5. Claire Donovan (Saracens)
6. Rachel Taylor (Cardiff Quins)
7. Catrina Nicholas (Cardiff Quins)
8. Mel Berry (capt) (Blaydon)
9. Amy Day (Bristol Ladies)
10. Elinor Snowsill (Loughborough)
11. Caryl James (Cardiff Quins)
12. Clare Flowers (Bristol Ladies)
13. Rachel Poolman (UWIC)
14. Lou Rickard (Woodbridge)
15. Non Evans (Cardiff Quins)
16. Jenny Davies (Waterloo)
17. Claire Horgan (Saracens)
18. Louise Horgan (Saracens)
19. Lisa Newton (UWIC)
20. Laura Prosser (Cardiff Quins)
21. Awen Thomas (Whitland)
22. Aimee Young (UWIC)