There is a variation in the width of coastal plain from 48 to 100 km. Large rivers cross this coastal plain and have built big deltas which are growing towards the sea. The deltas of the Mahanadi, the Godavari and the Krishna are fertile and are provided with irrigation facilities.
The Mahanadi Delta in the north merges into deltas formed by the Brahmani and the Baitarani. All these rives bring enormous quantities of water and sometimes cause dangerous floods during the rainy season, but during the summer season their channels are almost dry.
The deltas of the Godavari and the Krishna have enclosed between them a part of the sea known as Kolleru Lake. Another lake of large size is Chilka Lake which is situated to the south-west of the Mahanadi delta.
This region falls in tropical climate zone. Average monthly temperature is above 12°C throughout the year. Littoral of Andhra Pradesh north-east of East Godavari district receives about 102 cm of rainfall a year.
Orissa coastal lowland receives rainfall (about 152 cm. year) than the other parts of this region because it comes directly under the influence of weak tropical depression originating in the Bay of Bengal during the summer monsoon rainy season. The distinctive climatic feature is introduced in the climate of this region by tropical cyclones.
These cyclones which visit this coast sometimes cause immense damage to property and the standing crops particularly sugarcane both by strong winds and heavy downpour. Mangrove grows along the deltas where the rivers meet the sea.
This region is well endowed with fertile soil but there is prouiems of floods and drought. The irrigation canal has been dug from Godavari and Krishna Delta area. These two irrigation systems irrigate 8.9 lakh hectares.
These rivers have been dammed near the head of their deltas. A few kilometres down the river from Rajahmundry the Godavari is dammed near Dowlaishweram from where canals take off to irrigate almost the whole of the delta east of Kolleru Lake. The Krishna is dammed near Vijayawada.
The Mahanadi delta is also served with irrigation canals. In addition to irrigation the delta canals are used for navigation.
A variety of tropical crops are grown in this region. Rice is the dominant crops. The irrigated doabs in the deltas are particularly favourable for rice. In East Godavari and Krishna districts and the coastal plain of Orissa a little more than half of the total area is under rice.
Orissa coastal plain being more wet (Cuttack-annual rainfall 155.7 cm) produces jute as well. Jute is raised chiefly in the Mahanadi delta. Orissa coastal plain produces about 2.2 lakh bales (each bale of 180 kg.) of jute every year which constitutes 6 percent of India total.
Distinctive crops are cocount (mainly irrigated) in East Godavari district, Cigarette tobacco (mainly unirrigaed) in Guntur district and turmeric in Guntur and Krishna districts. Sugarcane is grown mainly in the coastal belt of Andhra Pradesh north of the Krishna due to facilities of adequate rain fall.
The region is par excellence the cigarette tobacco region of India and it produces 95% of this variety of India’s tobacco. It is raised in the Rabi season. It is concentrated in Guntur district accounting 10 percent area of this district. The soil is black and retains moisture received during the rainy season. As this crop is generally unirrigated, the moisture in the soil is very helpful for the growth of tobacco.
The region is an important supplier of edible copra which is marketed as cup copra or ball copra. Godavari Delta is the .richest coconut producing area.
Minerals and Power Resources:
There is variety of minerals in this region. Manganese ore is the leading mineral. It is mined mainly in the belt lying between Vizianagaram and Srikakulam. It is exported through Vishakhapatanam port. This region also produces about one-tenth of the total mica produced in India. It is produced mainly for export. A small amount of chromite is mined in the Kondapalli hill about 24 km. north- west of Vijayawara.
Crude oil and gas have been discovered both in onshore and off shore areas in the Krishna-Godavari delta. Gas has been struck mainly in the Krishna- Godavari basin but gas as well as oil on a few offshore locations. On shore gas has been struck at Chintalpalli, Narasipur, Razole, Kaza, Tatipaka, Bhimanpalli, Pasarlapudi and Endamuru.
The Mackhund hydro-electric project Supplies the northern part of this region with electricity. This project is located on the Mackhund, a subtribulary of Godavari. A dam has been constructed across the river at Jalapat 206 km north of Vishakhapatnam.
Modern factory industry of some significance is centred at Vishakhapatnam. At this place ships are built and imported petroleum crude is refined.
Ferro manganese and Ferro chrome are made at Shreermanagar which is about 88 km. to the north- eat of Vishakhapatnam. Modern large-scale industries have been set up.
Vishakhapatnam Steel Plant (V.S.P):
In 1992 this steel plant was completed which is located at a site 14 km. away from Vishakhapatnam town. It is the first coast-based integrated steel plant of India. The latest technology has been employed for making steel here.
The production capacity of the plant is 3.0 million tonnes of liquid steel per annum. The plant has been set up by Rashtriya Ispat Nigam Ltd. with erstwhile soviet Technical and financial assistance. High-grade iron ore lumps and fines are supplied by Bailadila Iron Ore Mines.
Coking coal of medium quality is brought from Jharkhand. Talcher supplies coal for boilers and 20 percent of the total coking coal required by the plant is imported from Australia. Thandava reservoir supplies water. A newly built 153-km long canal connects Yeleru reservoir in East Godavari district with the steel plant. This canal ensures the requisite supply of water.
Other industries are scattered in the region and are mostly agro-based. Cotton textile industry is located mainly at Cuttack, Rajahmundry and Eluru.