Sluices and a Dam Set Up at Guangtong in 1403

Background

Volume One of the Kangxi Lishui County Gazetteer records that the people of Lishui first petitioned: the low-lying land of Liyang and Lishui suffered repeatedly from floods, and they asked for a sluice at Guangtong to hold back and release water. A survey was sent, and reported that the water of the two counties received the streams of Ningguo and Guangde by way of Gucheng Lake and poured into the county whenever there were long rains, and that the waters of the Yanzhi River and Shijiu Lake, instead of running into the Yangtze, rushed down and damaged Suzhou and Songjiang as well. It was therefore proposed to build sluices and a dam at Guangtong, with an officer in charge.

Time and place

The works were set up in the fourth month of 1403, at Guangtong. The same report also names Yanzhi Hill and the mouth of Gucheng Lake. The gazetteer attributes the works to a local petition followed by a survey, not to a decision taken on engineering grounds alone.

What was done

成祖永乐元年癸未，四月，设溧水广通镇闸坝，置官一员。初，溧水民言溧阳、溧水洼下，数罹水患，乞于广通镇置闸，以备潴泄。遣人视之，还言，二县水由固城湖上纳宁国、广德诸水，每遇霖潦即注县境，且胭脂河与石臼湖诸水不入大江而奔注，苏松皆被其患。宜于胭脂山、广通镇及固城湖口二处筑闸坝，设官掌之为便。从之。 — Kangxi Lishui County Gazetteer, 卷之一·邑纪·成祖永乐元年癸未

Translated: In the fourth month of the first year of the Yongle era, sluices and a dam were set up at Guangtong in Lishui, with one officer appointed. Earlier the people of Lishui had said that Liyang and Lishui lay low and suffered repeatedly from floods, and asked for a sluice at Guangtong to hold back and release water. A survey was sent; it reported that the water of the two counties received the streams of Ningguo and Guangde by way of Gucheng Lake and poured into the county in every long rain, and that the waters of the Yanzhi River and Shijiu Lake, instead of entering the Yangtze, rushed down so that Suzhou and Songjiang also suffered. It would be convenient to build sluices and a dam at Yanzhi Hill, Guangtong and the mouth of Gucheng Lake, with an officer to manage them. The proposal was approved.

The outcome recorded is that the proposal was approved and carried out, with one officer appointed to manage the works.

Consequences

With the sluices in place the water of Liyang and Lishui had works that could hold it back or release it, under a dedicated officer. The arrangement lasted a little over a century: in 1512 Suzhou and Changzhou petitioned on grounds of flooding for a dam at Guangtong, and on the decision of the provincial authorities the dam was raised three zhang in height and thickness, the two sluices were sealed and their opening strictly forbidden. From that point the water above Guangtong had no outlet, and in 1600 the Lishui residents Zhang Xiao, Xiong Zicheng and others petitioned the throne, saying that more than 80,000 mu of fertile lakeside fields had been destroyed and the quota tax apportioned among the remaining households, and asking for the commutation of grain tax on the Gaochun precedent.

Uncertainties

First, the report names three places — Yanzhi Hill, Guangtong and the mouth of Gucheng Lake — but speaks of works at "two places". The gazetteer does not say which two were meant, and this entry reproduces the text without choosing between them.

Second, the title, office and term of the officer appointed are not recorded, nor are the form and dimensions of the works.

Third, the gazetteer does not say whether the two sluices sealed in 1512 were those set up in 1403; the two are presented here side by side.