I live in a city of a couple of million people.
The only place dratini spawn with any regularity is near the coast. For me, to go to a pokemon rich part of the coast is about 45 minutes away - and even then I have never been lucky when there...although friends have been lucky on a few rare occassions there.
I am in Facebook groups, and other sites, and you can be sure the city is very much 'searched' and even 'mapped' in places (not my thing but I know they exist).
We know where they spawn, and it is no where near me...so I have become a very good buddy with a dratini.
That said, I do have a couple of walking paths that spawn waters...as it is a dry creek bed in Summer, and flodway in Winter. Also, many parks with lakes and wetlands...so I can locate every other water biome mon relatively close, just no dratini.