River Rapti is the most important left bank tributary of the Ghaghra. It rises in Nepal at an elevation of about 3048 m. in the Dregaunra range. It has a total catchments area of about 23,906 Sq. km. out of which about 4588 Sq. k.m. lies in Nepal and the remaining in the State of U.P. The river has a total length of about 782 km. out of which 331 km. lies in Nepal. The flood water of river Rapti is being controlled by Rapti Barrage. This is situated at the up-stream of Bhinga site in district Shravasti and maintained by State government.

a) KAKARDHARI

The site is situated in Nanpara Tehsii of Bahraich district near the Indo- Nepal Border on the right bank of river Rapti. The gauge data of this site is utilized as a base data for formulation of flood forecast for the river Rapti at Balrampur, The site has its own CWC’s Wireless network for the transmission of data to divisional office and other places. The catchment area of river Rapti up to Kakardhari Is 5,926 sq. km.

The Geographical co-ordinates are as under:

Longitude : 81° - 49' E

Latitude : 27° - 51' N

Type of site : Gauge

b) BHINGA

The site is situated in district Shravasti very near to Indo-Nepal Border on the right bank of river Rapti. This site is operating since 1974. The catchment area of river Rapti up to Bhinga is 6,151 sq. km.

The Geographical co-ordinates are as under:

Longitude : 81° - 51' E

Latitude : 27° - 40' N

Type of site : Gauge and Discharge

c) BALRAMPUR

This is first forecasting site on the river Rapti in Balrampur district. The gauge data of Kakardhari is utilized as base data for formulation of forecast for Balrampur. The gauge data of the site is used as base data for formulation of forecast at Bansi. The site is near the road bridge on Bairampur-Tulsipur Road on the right bank of river Rapti. The catchment area of river Rapti up to Balrampur is 8,219 sq. km. This site is operating since 1974.

The Geographical co-ordinates are as under:

Longitude : 82° - 12' E

Latitude : 27° - 27' N

Type of site : Gauge,Discharge,Silt and Water Quality

d) BANSI

The site is situated about 1.5 km down-stream of the road bridge on Bansi- Naugarh road on the left bank of river Rapti. This is the second forecasting station on Rapti for which flood forecasts are issued. The gauge data of Balrampur is utilized as base data for formulation of forecast for Bansi. The gauge data of the site is used as base data for formulation of forecast at Birdghat. The site has its own CWC’s Wireless network for the transmission of data to divisional office and other places. The catchment area of the River Rapti up to Bansi is 9,575 sq. km. The Geographical co-ordinates are as under:

The Geographical co-ordinates are as under:

Longitude : 82° - 58' E

Latitude : 27° - 11' N

Type of site : Gauge

e) REGAULI

This site is located near village Regauli on left bank of the river Rapti down-stream of the confluence of river Kunhra. The catchment area of river Rapti up to Regauli site is 16,387 sq. km.

The Geographical co-ordinates are as under:

Longitude : 83° - 18' E

Latitude : 26° - 46' N

Type of site : Gauge, Discharge, Silt and Water Quality

e) BIRDGHAT

This site is situated near Gorakhpur town very close to Gorakhpur-Lucknow Road Bridge on the left-bank of river Rapti. This is the last flood forecasting station on river Rapti. The gauge data of Bansi and Kakrahi are utilized as base data for formulation of forecast for Birdghat. The site has its own CWC’s Wireless network for the transmission of data to divisional office and other places. The catchment area of river Rapti up to Birdghat (Gorakhpur) is 20,093 sq. km.

The Geographical co-ordinates are as under:

Longitude : 83° - 21' E

Latitude : 26° - 46' N

Type of site : Gauge, Discharge, Silt and Water Quality

TRIMOHANIGHAT

As the name implies, Trimohanighat site represents the confluence of three river of Rohin group. The idea behind the setting up of this site in 1971 was to determine the contribution during the flood of the river Rohin to the River Rapti. The site is situated just down-stream of the road bridge connecting Pharenda (Anand Nagar) with Mahraj Ganj on the right bank of river Rohin. The catchment area of river Rohin up to Trimohinighat is 2,355 sq. kms.

The Geographical co-ordinates are as under:

Longitude : 83° - 25' E

Latitude : 27° - 06' N

Type of site : Gauge

The BurhiRapti is the most important tributary of the river Rapti. It rises in the Dundwa range at an elevation of about 914.4 m. and has a steep drop of about 609 m. in about 16.1 km. of its flow. It flows roughly parallel to Rapti and in high floods it inundates a large area. It joins the river Rapti near the village Balashir in district Basti. The tributaries of BurhiRapti are mostly non-perennial streams except the Banganga. The BurhiRapti drains a catchments area of 4,701 Sq. km. and has a length of 198.3 km.

KAKRAHI

To ascertain the contribution of river Burhi Rapti, a major tributary of river Rapti, Gauge observation at Kakrahi was started in 1971. Subsequently, the site is upgraded as Gauge & Discharge site in Year 2004. The gauge data of the site is used as base data for formulation of forecast at Birdghat. The site is situated just down stream of the confluence of Banganga river with the river Burhi Rapti near Road Bridge on Bansi Naugarh road in Sidharthnagar district. The site is situated on the right- bank of river Burhi Rapti. The catchment area of river Burhi Rapti up to Kakrahi is 4,192 sq. km.

The Geographical co-ordinates are as under:

Longitude : 82° - 59' E

Latitude : 27° - 14' N

Type of site : Gauge and Discharge

USKABAZAR

To ascertain the contribution of river Kunhra, a tributary of river Rapti, Gauge site at Uska Bazar on right bank of river Kunhra about 30 metre down¬stream of the Railway bridge on Railway line Uska Bazar- Brijmanganj in district Sidharthnagar is setup in 1971. The catchment area of river Kunhra up to Uskabazar is 2,432 sq. km.

The Geographical co-ordinates are as under:

Longitude : 83° - 09' E

Latitude : 27° - 12' N

Type of site : Gauge