Saturation System
It is one of the methods to determine the best alternative based on maximum utility of road network. The factors which are taken for obtaining the utility per unit length of road are: i) Population served by the road network
ii) Productivity served by the net work
a. Agricultural products
b. Industrial products
Since the area under consideration may consist of villages and towns with different populations, it grouped into some ranges and assigned utility units.
Population less than 500, utility unit = 0.25
501-1000, utility unit = 0.50
1001- 2000, utility unit = 1.00
2001 – 5000, utility unit = 2.00 etc..
Similarly the agriculture products for tonnes productivity, utility units = 1
Industrial products for tonnes productivity, utility units =10 etc.
The various steps to be taken to obtain maximum utility per unit length are:
1.Population factors or units: Since, the area under consideration consists of villages and towns with different population these are grouped into some convenient population range and some reasoning values of utility units to each range of population serve are assigned.
2.Productivity Factors or units: The total agricultural and industrial products served by each road system are worked out and the productivity served may be assigned appropriate values of utility units per unit weight.
3.Optimum Road length: Based on the master plan the targeted road length is fixed for the country on the basis of area or population and production or both. And the same may be taken as a guide to decide the total length of the road system in each proposal.
First Twenty Road Plan (Nagpur Road Plan )
The conference of chief engineer held at Nagpur in 1943 for first twenty road development plan (1943-1953). The roads were classified into five major categories. Recommendations were made for the geometric standards of roads, bridges and highway organization. Two formulae were finalised based on star and grid pattern to calculate the road length for the country as a whole.
Classfication of Roads
i) National Highway ( NH): are main Highways running through the length and breadth of India, connecting major ports, foreign highways, capitals of large states and large industrial and tourist centres including roads required for strategic movement for the defence of India. Examples: NH-1: Delhi-Ambala- Amritsar. NH-1-A: Bifurcation of NH-1 beyond Jalandar to Srinagar and Uri.
ii) State Highway (SH): are arterial roads of a state, connecting up with the national highways of adjacent state, district head quarters and important cities within the state and serving as the main arteries for traffic to and from district roads. Examples: SH17 – Bangalore- Mysore.
iii) Major District Roads (MDR) : are those roads with in a district serving area of production and markets and connecting those with each other or with the main highways of a district.
iv) Other District Roads: are roads serving rural areas of production and providing them with outlet to market centres, taluk head quarters, block development head quarters or other main roads.
v) Village Roads (VR): are roads connecting villages or groups of villages with each other to the nearest road of a higher category.
Salient Feature
i) The responsibility of construction and maintenance of national highways were assigned to the central government.
ii) Planned for 20 year (1943-63) aiming to provide 2 lakh km of surfaced roads and remaining un surfaced roads. Total targeted road length 5,32,700 km . Achieved 7, 09,122km by the end of 1961.(road density 16km/100sqkm).
iii) The road length formulated is based on star and grid pattern. But due consideration was given for existing irregular pattern and obligatory points not fitting in the geometric pattern.
iv) The size of grid is 16km so that max distance from the centre is 8km and average distance from village road to metalled road is 3.2 km.
v) The ODR and VR are meant to provide internal road system linking to Higher category of road network.
vi) An allowance of 15 % was given for agricultural and industrial development during next 20 years.
vii) The length of railway tracks in the area was also considered in deciding the length of the first category of road.
Formulae
NH+ SH+ MDR (km) = [A/8 + B/32 + 1.6N + 8T] +D – R
ODR+ VR (km) = [0.32V + 0.8 Q + 1.6 P + 3.2 S] + D
Where, A= agricultural area, km2
B= Non-Agricultural area, km2
N = number of towns and villages with population range 2001-5000.
T= number of towns and villages with population over 5000
D = Development allowance of 15 percent of road length calculated to be provided for agricultural and Industrial during the next 20 years
R= Existing length of railway track in km.
V= Number of villages with population 500 or less
Q= Number of villages with population range 501-1000
P = Number of villages with population range 1001-2000
S= Number of villages with population range 2001-5000
Second Years Twenty Road Plan (1961-1981) Bombay Road Plan
This plan envisaged overall road length of 10,57,330 km by the year 1981 ( achieved . The cost of the plan has been worked out to Rs. 5,200 crores based on 1958 price level. Five different formulae were framed to calculate the length of NH, SH, MDR, ODR and VR. Classification of the Roads by Bombay Road Plan:
i) Express way: are those connecting major capitals and other important centre with in the country where the traffic density is high and the vehicles are allowed to travel with no cross interruption. The express way are constructed with high design standards and design speed.
ii) NH, SH, MDR, ODR & VR.
Salient Feature
1. Drawn on more scientifically in view of development needed in under developed areas. Targeted road density 32km per 100 sqm, road length of 10,57,330 km, achieved road length = 15,02,697km.
2. Maximum distance of any place in a developed or agricultural area would be 6.4 km from a metalled road and 2.4 km from any category of roads.
3. Every town with population above 2000 in plains and above 1000 in semi-hill areas and above 500 in hilly areas should be connected by a metalled road.
4. While calculating the road length in hilly regions, an allowance upto 100 percent to be made in arriving at the road length.
5. Expressways have also been considered in this plan and 1600 km of length has been included in the proposed target of National Highways.
6. Length of railway track is considered independent of the road system.
7. The development factor of only 5 % is provided for future development and unforeseen factors.
Formulae
NH = [A/64+ B/80 +C/96 + 32K + 8M] +D
NH+ SH, (km) = [ A/20 + B/24 + C/32] + [ 48K + 24 M + 11.2 N + 1.6 P] + D
NH + SH+ MDR ( km) = [ A/8 + B/16 + C/24] + [ 48 K + 24 M + 11.2 N + 9.6 P + 6.4 Q+ 2.4 R] + D
NH+SH+MDR+ODR, (km) = [3A/16+3B/32+C/16] + [48K +24 M + 11.2 N +9.6P + 12.8 Q + 4R + 0.8 S + 0.32 T] + D
NH+SH+ MDR+ ODR+ VR (km) =[ A/4 + B/8 + C/12] + 48K + 24 M + 11.2 N + 9.6 P + 12.8 Q + 5.9 R + 1.6 S + 0.64 T + 0.2 V] +D
Where, A = Developed and agricultural areas; km2
B= Semi-developed area,
C = Underdeveloped area,
K = number of towns with population over 1,00,000
M = number of towns with population range 1,00,000 – 50,000
N = number of towns with population range 50,000- 20,000
P = number of towns with population range 20,000- 10,000
Q = number of towns with population range 10,000- 5,000
R = number of towns with population range 5,000- 2,000
S = number of towns with population range 2,000- 1,000
T = number of towns with population range 1,000- 500
V = number of towns with population range below 500
D = Development allowance of 5 percent of road length calculated for further development and other unforeseen factors.