user: Question: What is the highest latitude when there are more than 0.518 square miles of water, a longitude less than -99.830606, and a population of 18?
Columns: ['Township', 'County', 'Pop. (2010)', 'Land ( sqmi )', 'Water (sqmi)', 'Latitude', 'Longitude', 'GEO ID', 'ANSI code']
Types: ['text', 'text', 'real', 'real', 'real', 'real', 'real', 'real', 'real']
Sample row: ['Caledonia', 'Traill', 111.0, 29.539, 0.0, 47.454423, 96.911195, 3809711540.0, 1036689.0]
SQL:

assistant: SELECT MAX("Latitude") FROM "Table" WHERE "Water (sqmi)" > 0.518 AND "Longitude" < -99.830606 AND "Pop. (2010)" = 18.0;