The climate of Ambala over most of the year is a pronounced continental in character.It is very hot in summers and markedly cold in winters.May and June can be really hot with the temperature soaring to over 48°C,while in winter it can be as low as -1°C. Ambala has a semi-arid as well as tropical climate.Being far away from the coasts and close to the Thar desert,it does not get the full share of the Monsoon current seen mostly across central and east of the country.
Around 70% rainfall is received during the month of July to September and the remaining rainfall is received during December to February.Ambala is the maximum rain-hit area in Haryana with average rainfall being 47.16 inches per annum.
River System & Water Resources
The district is mainly drained by non-perennial streams and the drainage system of the district comprises of the following:
1. The Markanda & its tributaries
2. The Dangri (Tangri) & its tributaries
3. The Ghagghar & its tributaries
The Markanda and the Dangri streams ultimately drain into the Ghagghar river beyond the territory of the district. The Ghagghar along with its tributaries however constitutes an inland drainage system.
The Markanda which drains the southern slopes of Dharti Dhar range (Himachal Pradesh), cuts through the shivalik range and enters the plains and the district. The river channel which is broad between Kala Amb and Mullana becomes narrow to the south of Mullana. During the rainy season, the river carries enormous water which causes flooding in its lower course.
The Tangri streams rises in the Morni Hills and flows in a southerly direction upto village Chajju Majra where it is joined by the Baliali Nadi. It further flows a southerly course running on the eastern side of Ambala Cantonment. After crossing the Ambala Cantonment Ambala-Jagadhari railway line it takes south-westerly direction . Near the villages of Segta & Segti the torrent of Omla and Amri join the Dangri. It is here that the Narwana branch of Bhakhra main canal crosses the Dangri stream. Thereafter the Dangri takes a westerly course upto village Niharsi where it turns towards south and leaves the district to enter the Patiala district of Punjab.
The Dangri rising from Morni Hills , used to flow on a southerly direction upto Panjokhra, a village in the North-East of Ambala from where it was separated into two main channels. These two channels still kept a southerly course running on either side of Ambala cantonment. The Dangri seems to have changed its course towards the close of 19th century when the drainage was confined to the eastern channel.The Baliali Nadi rises in the southern slopes of the Morni Hills and joins the Dangri stream near village Chajju Majra. The Amri ( also known as Shahzadpur wali or Dadri) is formed of water collected in plains during the rainy season. It starts near Rataur and flows south-west and takes the torrent of the Omla and joins the Dangri between the villages of Segta and Segti.
The Ghagghar, another important river also traverses the district for some distance in the north west. The river originates in Sirmaur district of Himachal Pradesh and enters the district. It traverses the district near Ambala City for a very short distance and then flows parallel to the district boundary outside the district .While in its-upper course , the river contains some water throughout the year, in its lower course it is generally dry in summer and carries water only during the rainy season.The two tiny lakes at an elevation of 620 metre above mean sea level near village Masiyun in the Morni hill tract are of little importance as these lakes neither feed any major stream nor are these being fed by any major river. Only a small stream from one of these lakes joins the Dangri (Tangri) nadi. Despite the large number of drainage lines passing through the district, the area suffers from inadequate water resources. Canal irrigation, which is limited to a few small pockets in the south-western tip of Ambala tehsil, does not have much scope for extension because of undulating topography in a large part of the district. Thus, wells and tubewells remain the major source of irrigation in the district.
Two bands of limestone one about 13 metre thick and the other about 25 metre thick, both extending over 500 metre have been located at Tundapathar. It is very high grade limestone with an average of 93 percent Calcium Carbonate and low in Magnesium Oxide.The estimated reserve is about 6 lakh tonnes. A band of thinly bedded Sabathu limestone, about 5 metre thick, occurs at Barun in Naraingarh tehsil. A band of limestone, about 20 metre thick and about 1.2 kilometre long occurs at Kharag. The total reserve in the area is estimated at 50 lakh tonnes of good quality limestone.The largest deposit of this area occurs at Ramsar and Sherla (Naraingarh tehsil). The limestone is well bedded about 30 metre thick and extends for about 2.4 kilometres. The reserve is estimated at about 120 lakh tonnes. The limestone belt extends to Malla (Kalka tehsil), Jonpur, Dabsu, Ambri and Jabial in Naraingarh tehsil.
A small quantity of salpetre is extracted from the soils around Ambala and Barara.The ground water in the district occurs under confined and semi-confined conditions. The depth of water level varies greatly in the area immediately to the south of the Shivalik hills. It ranges between 2 and 47 metre, maximum being towards the hills. The water level in the area further south ranges between 1.5 and 1.2 metre, but generally it varies between 4 and 8 metre. The shallow tubewells are usually constructed down to a depth of 10 to 45 metre. However at some places as in Nagia-Mullana belt, have been drilled to a depth of 90 metre. Shallow tubewells usually tap ground water from single aquifer. The deep tubewells generally range in depth between 91 and 185 metre but at few places tubewells down to 445 metre have also been constructed. Ground-water is generally fresh and suitable for domestic and irrigation purposes.
Seismically Ambala district lies in a region where earthquakes of moderate to great intensity have been experienced in the past. Being situated very close to the Himalayan Boundary Fault Zone, it is prone to earthquake shocks originating there. History of the past two hundered years for which records are available shows that during the Kangra earthquake of 1905, Ambala district experienced an intensity of VII-VIII M.M.(Modified Mercalli Intensity Scale of 1951). A committee of experts under the auspices of Indain Standard institution prepared seismic zoning map of India, where Ambala district has been placed in zone IV Where a maximum seismic intensity VIII M.M. is likely to reach in future earthquakes.Taking into consideration the above factors and also the fact that the extreme cases of high intensity occur only at long intervals, it is felt that a provision of seismic ground acceleration of 10 percent gravity (.10 g) may be made for engineering structures founded on well consolidated soil. For weaker foundations and important structures, the seismic factor may be suitably increased.