Rivers of Thailand

Basin Chao Phraya

Chao Phraya River

แม่น้ำเจ้าพระยา

The main river of central Thailand. It is formed where the Ping River and the Nan River meet at Pak Nam Pho in Nakhon Sawan province. It flows through the central plains and Bangkok to the Gulf of Thailand in Samut Prakan province.

Map of the Chao Phraya RiverKanchanaburiUthai ThaniLop BuriPrachin BuriAyutthayaPathum ThaniSaraburiNonthaburiRatchaburiSamut PrakanNakhon SawanBangkokChao Phraya Dam
The dark line is this river; the mid-blue lines are its named tributaries.

Key facts

Length
about 380 kmMeasured along the river on this map; official figures can differ with the method used
Source
Nakhon Sawan province
Flows into
Gulf of Thailand, Samut Prakan province
Provinces (10)
Nakhon Sawan, Chai Nat, Uthai Thani, Sing Buri, Ang Thong, Phra Nakhon Si Ayutthaya, Pathum Thani, Nonthaburi, Bangkok, Samut Prakan
Dams on the river
Chao Phraya Dam

Chao Phraya River water level today

20 automatic gauging stations on this river, highest water relative to the bank first. As of 29 Sep 2026, 21:50

StationLocationLevel (m MSL)Of bank-fullStatusMeasured
Khlong Lat Bang Yo 2 GatePhra Pradaeng District, Samut Prakan1.78135%Over the bank29 Sep 2026, 19:20
Chao Phraya 4Mueang Chai Nat District, Chai Nat18.61107%Over the bank29 Sep 2026, 21:50
Chao Phraya 12Bang Pa-in District, Phra Nakhon Si Ayutthaya3.08104%Over the bank29 Sep 2026, 21:50
บ้านป้อมPhra Nakhon Si Ayutthaya District, Phra Nakhon Si Ayutthaya4.90104%Over the bank29 Sep 2026, 21:00
Chao Phraya 14Pak Kret District, Nonthaburi2.46100%High29 Sep 2026, 21:50
กรมชลประทานสามเสนDusit District, Bangkok1.9298%High29 Sep 2026, 21:00
Chao Phraya 7Phrom Buri District, Sing Buri9.8195%High29 Sep 2026, 21:50
Chao Phraya 11Phra Nakhon Si Ayutthaya District, Phra Nakhon Si Ayutthaya4.4694%High27 Sep 2026, 23:00
Chao Phraya 15Thon Buri District, Bangkok1.1194%High29 Sep 2026, 21:50
Chao Phraya 8Mueang Ang Thong District, Ang Thong7.7492%High29 Sep 2026, 21:50
Chao Phraya 5Sapphaya District, Chai Nat14.0690%High29 Sep 2026, 21:50
ท้ายเขื่อนเจ้าพระยาSapphaya District, Chai Nat14.8189%High29 Sep 2026, 21:00
บ้านบางแก้วMueang Ang Thong District, Ang Thong8.0889%High29 Sep 2026, 21:00
บ้านบางพุทราMueang Sing Buri District, Sing Buri11.4088%High29 Sep 2026, 20:00
Khlong Lat Bang Yo 1 GatePhra Pradaeng District, Samut Prakan1.2087%High29 Sep 2026, 21:50
Chao Phraya 6In Buri District, Sing Buri12.9584%High29 Sep 2026, 21:50
Chao Phraya 2Phayuha Khiri District, Nakhon Sawan19.5784%High29 Sep 2026, 21:50
Chao Phraya 1Mueang Nakhon Sawan District, Nakhon Sawan22.8983%High29 Sep 2026, 21:50
ค่ายจิรประวัติMueang Nakhon Sawan District, Nakhon Sawan23.1980%High29 Sep 2026, 21:00
Chao Phraya 3Manorom District, Chai Nat16.1760%Normal29 Sep 2026, 21:50

Data from the National Hydroinformatics Data Center (ThaiWater), HII, refreshed every 10 minutes

Frequently asked questions

Which provinces does the Chao Phraya River flow through?
The Chao Phraya River flows through 10 provinces: Nakhon Sawan, Chai Nat, Uthai Thani, Sing Buri, Ang Thong, Phra Nakhon Si Ayutthaya, Pathum Thani, Nonthaburi, Bangkok and Samut Prakan.
How long is the Chao Phraya River?
The Chao Phraya River is about 380 km long, measured along the river on this map. Official figures can differ slightly with the method used.
Where does the Chao Phraya River come from?
The Chao Phraya River rises in Nakhon Sawan province.
Where does the Chao Phraya River reach the sea?
The Chao Phraya River flows into the Gulf of Thailand in Samut Prakan province.
Which dams are on the Chao Phraya River?
Dams on the Chao Phraya River on this map: Chao Phraya Dam.
What is the Chao Phraya River water level today?
Of 20 gauging stations, 4 are over the bank and 15 have high water. Data as of 29 Sep 2026, 21:50.
What is the Chao Phraya River called in Thai?
In Thai the Chao Phraya River is แม่น้ำเจ้าพระยา.

Other rivers in the Chao Phraya basin

Noi River