Wat Tha Phai or the "Monastery of the Landing of the Paddle" is a vanished temple formerly located on the city island in present Pratu Chai sub-district, in the vicinity of an area formerly called Laem Sarapha. The monastic structure was located near "China Street" and Khlong Nai Kai, presently called Khlong Makham Riang.
Historical data about the monastery and its construction are unknown. The 19th century map indicates no existence of a chedi or prang.
The temple is mentioned on Phraya Boran Rachathanin's (PBR) map drafted in 1926 as Wat Singthai (วัดสิงหทาย). Its name has been presently altered to Wat Singha Sai (วัดสิงหาทราย), maybe referring to lions in sandstone found on the former temple grounds.
Making an assessment off all the monastic structures, in the zone demarcated by Chikun Rd, Pa Thon Rd, Pridi Banomyong Rd and U-thong Rd is rather difficult, as the position and name of the structures varies on different maps. On a 19th century map there are 15 structures counted, while on the 20th century PBR map there are 13 mentioned. There is inconsistence in the names and the positions. Even a map drafted in the 90's by the Fine Arts Department, what I presume, based on excavations in the zone, shed no light on this matter. Positions of monastic structures can be asserted, but their ancient names will remain questioned forever.
Footnotes:
(1) Phraya Boran Rachathanin positions Wat Noi Nang Hong more north than the 19th century map does. The location of Wat Noi Nang Hong on the 19th century map is called Wat Jin by PBR.