Brief Description of the Basin

• Tapi basin is situated in the northern part of the Deccan Plateau.

• Extends over an area of 65,145 km.

• The basin lies between east longitudes of 72º 38' to 78º 17' and north latitudes of 20º 5' to 22º 3'.

• It is bounded on the north by the Satpura range, on the east by the Mahadeo hills, on the south by the Ajanta range and the Satmala hills and on the west by the Arabian Sea. Bounded on the three sides by the hill ranges.

• The culturable area of the basin is about 4.29 Mha.

• The forest cover is about 25% of the area in the basin.

• Physiographically, the area is a basaltic landscape with major physiographic units of plateau lands, escarpments, hills, piedmont plains, colluvio-alluvial plains and valley plains.

• The entire Tapi basin can be divided in three sub-basins: Upper Tapi Basin up to Hathnur [confluence of Purna with the main Tapi (29,430 sq. km)], Middle Tapi Basin from Hathnur up to the Gidhade gauging site (25,320 sq. km), and Lower Tapi Basin from the Gidhade gauging site up to the sea (10,395 sq. km). The annual rainfall for the upper, middle, and lower Tapi basins for an average year is 935.55 mm, 631.5 mm, and 1,042.33 mm respectively.

Drainage Area of the Basin

Name of State

Drainage area ( Km²)

  Madhya Pradesh

                                 9,804

  Maharashtra

                               51,504

  Gujarat

                                3,837

Total Drainage Area of Tapi Basin (in Km²)                                               65,145

Topography

The Tapi basin has two well-defined physical regions, viz., the hilly regions and the plains. The hilly regions cover the Satpura, the Satmala, the Mahadeo, the Ajanta and the Gawilgarh hills and are well forested. The plains cover the Khandesh plains which are broad and fertile areas suitable for cultivation. The culturable area of the basin is considered as the total of the land under miscellaneous crops and trees, current fallows, other fallows, culturable wasteland and net area sown.

The basin in Madhya Pradesh is mostly covered with Deccan trap lava flows. The other formations found in the basin are alluvium, lower Gondwana, Cuddapah system, Bijawar series, and granites gneiss. Most of the area of Tapi basin falling within Maharashtra state is full of cuts & valleys. Lands on the right side of the river lying on southern slopes of Satpura hills consist of black soils. The soil cover is deep and rock is found at greater depths. Lands on the left side of the river on northern slopes of Sahyadri consist mainly of dykes & red murrum soil and are rocky in most parts.

Water Potential of the Basin

Surface Water potential

14.88 Km³

Ground Water potential

8.27 Km³

Hydropower Potential

Water Utilization

Surface Water Utilization

Drinking purposes

Irrigation purposes

Ground Water Utilization

Drinking purposes

Irrigation purposes

Tributaries

Vaki, Aner, Arunawati, Gomai, Nesu, Amravati, Buray, Panjhara, Bori, Girna, Waghur, Purna, Mona, and Sipna

Major & Medium Projects

Sonkhedi Tank, Sukta, Chandora, Katepurna, Nalganga, Uma, Nirguna, Morna, Gyanganga, Mos, Paltag, Man, Thoran, Hathnur, Girna, Manyad, Bori, Suki, Abhora, Boker Bari, Agnawati, Tondapur, Aner, Karwand, anjhra, Malangaon, Kanholi, Burai, Arunawati, Rangawali, Nagasakya, Haran bari, Ukai, Kakrapar, Lakhigav, Ver

Water Quality of Tapi Basin

 Water Quality Status at Different Locations in Tapi River in 2001

Location

Desired Class

2001

Tapi at Nepanagar, M.P.

A

   B, Totcoli

Tapi at Burhanpur, M.P.

A

   B, Totcoli

Tapi at Hathnur, M.P.

A

   B, Totcoli

Tapi at Ajnand Village, Maharashtra

   D, BOD, Totcoli

Tapi at Bhusawal U/S, Maharashtra

C

   D, BOD

Tapi at Uphad Village, Maharashtra

   D, BOD

Tapi at Ukai, Sherula Bridge, Gujarat

C

      NA

Tapi at Mandavi, Gujarat

C

      NA

Tapi at Kathore, (NH-8 Bridge), Gujarat

C

     NA

Problems in Water Resources Development of Tapi Basin

During monsoons, the Tapi River is frequently in spate and floods occasionally cause havoc in the plains of lower reaches. In the post-monsoon period, the discharge in the river is quite low, say of the order of 300 cumec. In the basin, rain storms typically move from east to west; this also is the general flow direction in the basin. Most floods occur during the period July to September, though occasionally they may occur in the second week of October. The maximum number of floods has been found to take place in the month of August.

Floods were a frequent phenomenon in Tapi River at Surat before the Ukai Dam was constructed. During 1876 to 1970, danger level was crossed at the Hope Bridge, in Surat on 19 instances. This implies a frequency of once in every five years. High floods were experienced during three consecutive years from 1882 to 1884. There was a very high flood in August 1944 and actually two almost similar flood peaks occurred in the same week. A heavy flood, only slightly lower than that in 1944, was experienced again in 1945. Consecutive large floods were also observed in 1958 and 1959. Heavy floods were witnessed in 1968, 1969, and 1970. The floods of September 1959 and August 1968 were catastrophic. The floods of 1994 and 1998 also caused considerable damage to the Surat city and other low-lying areas on the downstream.

Mythology

Also known by the name Tapti, Tapi was a daughter of Sun. Ptolemy named it Nanagouna. It is believed that Tapi rises from the sacred tank of Multai (Mulatapi, i.e., the source of Tapi). The Tapi has its name derived from tapa, ‘heat’ and according to local Brahmanas, it was created by the Sun to protect himself from his own warmth.