The Dragon Gate formula was written for sites with streams and ponds, and most city buildings have neither. What a city site does have is flow — the fall of the ground, drains and gutters, and roads that carry movement toward and away from a building. Many practitioners read roads as "virtual water"; the formula’s own sources already name roads striking toward a house among the things read as harmful at its 天劫 and 曜煞 positions.
What counts as flow on a city site
Start with real water: where rain falls away from the building, where the gutters and drains discharge, which side of the plot is lowest. Then the roads: a road running toward the building from one direction and past it toward another behaves, for this reading, like water arriving and leaving. A road or a building corner pointing straight at the house from a 天劫 or 曜煞 direction is the configuration the sources warn about.
A worked example: a house sitting in 離
A house with its back to the south (sitting 離, facing north). Its formation: 先天 east, 後天 northwest, 賓 west, 客 southwest, 天劫 northeast, 地刑 northwest, 案劫 north (the front), 輔卦 southeast. The formula looks for flow arriving from the east or the northwest and leaving toward the northeast or the north; the water mouth is the 艮, 壬 and 癸 mountains. A street that runs in from the east and away past the north-facing front follows it. The same street running in from the northeast — the 天劫 — is the worst case, and a drain that empties toward the east or northwest breaks the 先天 or 後天.
When the configuration is hostile
Most city buildings cannot move their streets. What can change is the smaller flow the building controls: where its own gutters and drains discharge, how the forecourt falls, where a path or driveway leads. The sources’ list of things striking from the 天劫 direction — poles, corners, roads — is a list of what to screen or soften, not a prediction. Measure the facing carefully first: every position here moves if the house turns out to sit in the neighbouring palace.
References
Canonical sources that inform this guide.
- 论龙门八局系水法 (华夏大易学社) · WEBSITE
- 三元水法龙门八大局 (简书) · WEBSITE
- Bagua (Eight Trigrams) · WIKIPEDIA
- Feng shui · WIKIPEDIA