The Lake Vista neighborhood was reclaimed from the lake bottom, laid out, and built by the New Orleans Levee Board in the mid-1930's. They built a seawall, thereby creating a well-defined lakeshore, about a mile or so beyond (i.e., north of) where mostly-dry land formerly began gradually turning into swamp and then lake. The neighborhood is a notable example of a planned community ~ houses face each other across parklike, unpaved "commonses" while vehicular traffic navigates streets towards which the backs of the houses (and the fronts of the garages) face.

My late mother-in-law used to say that Lake Vista and the larger "Lakeview" district of which it is a part were "built on eggshells and coffee grounds." It is definitely true that the land upon which this pricey real estate is built is less than stable, thanks to being reclaimed from the Shores of the Pontchartrain. Streets need repaving much more often than in other areas of the city, and even the foundations of houses are shakier there than elewhere.

This has probably been explained well enough already, but: Yes, the city has "grown," but in regards to its northern boundary, the growth (in terms of reclaimed lake bottom) only means that the north shore of the lake is only 26 miles away now, instead of 27 or 28. Five miles north of town is still way out in the water.