In the Name of Allah

Watershed Management in Iran

with emphasis on erosion and sediment

control

By : Seyed abolfazl mirghasemi

Contents :

• Objectives• History and evolution of watershed

management• Natural Features Of Iran (climate, land use ,geology)

• Reservoir dams of Iran• Soil erosion in Iran• Planning for erosion study & control• Applied Measures

Objectives :

Conservation and development of water, soil and plant resources

Soil erosion and sediment controlFlood control & spreadingGround water Recharge & Mitigation of

drought ConsequencesImprovement of living standards and welfare

of local communities;

History of watershed Management In iran

• IRAN has practiced Watershed Management since 3000 years ago. The historical hydraulic structures , water harvesting systems , water supply systems and working on hillslope shows the efforts of Iranians in the past.

• Qanats, construction of earth dams, Masonry dams, Irrigation Canals, Traditional Rain Water Harvesting System (khoshab & bandsar) and terracing on steep slopes for cultivation are some of the examples.

Traditional systems of soil & water conservation

IRAN-Bushehr IRAN-Baluchestan

Traditional system soil & water conservation

IRAN - Fars IRAN - Kermanshah

Traditional system soil & water conservation

IRAN-fars & Bushehr

History and evolution of Watershed Management in Iran

FAO report about critical situation of Soil Erosion in Iran

in 1958

Establishment of Soil & Water Conservation Committee

in 1958

Implementation of Soil Conservation Pilot Project, by FAO

in 1959

Flood Damages in 1968and

Sedimentation Problems in the Reservoir of 6 Big Dams

Establishment of Soil Technical Office in 1968Establishment of Soil Technical Office in 1968

Restarting of Watershed Management Activities ,in Karaj, Sefid-Rood and Dez River Basinsin 1969

Restarting ofWatershed Management Activities in Karaj, Sefid-Rood and Dez River Basins, in 1969

Preparation of the First Watershed Management Master Plan byIranian experts in 1976

Preparation of theFirst Watershed Management Master Plan by Iranian experts in 1976

Progress in Watershed Management Activitiescaused necessity of Coordination & Cooperation

Establishment of Watershed Management Superior Council in 1972

Establishment of Bureau of Soil Conservation and Watershed Management in1972

Separation of Wind & Water Erosion Controls sectors in 1973

Reform in Watershed Management Organization and

establishment of Watershed Management Deputy under Ministry of Jihad-e-Sazandegi in 1991

Similar / Parallel works between Watershed Management Deputy & Forest and Range Organization

Reform in Watershed Management Organization by considering both sectors

under one Organization SINCE 2001

overview on Natural features of IRAN

Photo Mosaic of Landsat ETM+ Images in 2000-2002

Climate:

• Predominant climate of Iran is Arid – Semi Arid

• Mean annual of precipitation is 250 mm• Rainfall ranging from 50 – 2000 mm• %75 of precipitation in autumn- winter & %25 in

spring

:Forest:Forest

Land use in IranLand use in Iran

Million ha. 14.3

:Range:Range

Desert:Desert:

Cultivated land & etcCultivated land & etc

85

Million ha. 32.8

27.6

Million ha.

Million ha.

Range classification• Good rang :7.2 mhaModerate range : 21.45 mha

Poor range : 56.31 mha

Forest

Commercial forest (hircanian) 1.9 mha Semi dense forest (zagros) 12.1 mha

Desert & Sand dune

Desert : 32.8 mha

Geological description

• Iran is divided into 4 geological zones:• 1- Alborzo Zone• 2-Zagros zones• 3- khuzestan plain• 4- central iran zones• Existence of extensive neogene rocks and

quaternary deposits are the main sources of sediment

High Erodible & soft rocks and soils

Clay Marl

LoessMarl

Reservoir Dams

•Aras dam Sefidrud dam

Soil erosion in Iran

Gully

Sheet &Rill

Landslide

Bank erosion

Area under Accelerated Soil Erosion

Area under Accelerated Soil Erosion

Quantity of erosion in Iran

Quantity of erosion in Iran

Million ha. 125

B tones / yr Total annual Soil erosionTotal annual Soil erosion

Area with High Runoff:Area with High Runoff:

Specific ErosionSpecific Erosion

Area under FloodsArea under Floods

2

Million ha. 91

Tons/ha /yr255 Cities

8650 Villages

Roads & Infrastructures

20000 Qanats 1000000 ha Arable Lands

16.45

مي درصد درآمد ناخالص ملي14هزينه فرسايش در ايران معادل .باشد

1991امور بررسيهاي برنامه عمران سازمان ملل، مأخذ:

ده: گزارش FAO ساله آبخيزداري ، به نقل از مأخذ

1 1.3 1.6

2.21.9

0

2

4

6

1350 1360 1370 1380 1390

Btones/yearsميلياردتن درسال Trend of soil erosion in IranTrend of soil erosion in Iran

محيطي ا زيست ثراتشاس عمليات

رود زيستگاه بر سفيد رودخانه آبزيان

گزارش بهگيالن استان زيست محيط كل اداره

دريچه تخليه رسوب سد سفيد رود

هدف: جمع آوري و ذخيره آب است يا رسوب ؟!

مخزن سد سپيد رود که پر از رسوب شده است!؟

از ) شده حمل روان های شن و بادی فرسایش معضلمی پایین دریاچه آب سطح که مواقعی در سد مخزن

سد( مخزن حاشیه روستاهای اراضی در باشداستان) سفلی طارم منطقه در سیاهپوش روستای

قزوین(

پايين دست سد سپيد رود پس از عمليات شاس و

مردمي كه در حال گرفتن ماهی از آب گل آلود می باشند !

فاجعه زيست مجيطی در پايين دست سد !؟

صيد و صياد !؟

Effective factors in Soil erosion

Natural factors : Hilly Terrain Erodible rocks Poor vegetation cover Arid & Semi-Arid

Climate

Man made Factors: Land use change Over grazing Plughing in slope

direction Deforstation Mining Operation Mis-Practice in Agricultur

Over grazing : The number of livestock is 2.5 to 3 times of carrying capacity of rangelands

Natural Erosion (Geological)

%10 percent of catchment area contribute in production of %50 of sediment

Planning & study for W.M

• Watershed planning in 3 scale is implemented

• 1- First phase on Scale(1:250000)• 2- second phase on Scale 1:50000• 3- Third phase on scale 1:25000

Basins and watersheds of Iran

• Iran is divided into 6 great basins:

• 1-Caspian Sea• 2- Qaraqoom• 3- hamoon• 4- Persian Gulf & Oman

Sea• 5-Orumieh lake• 6- Central Desert

39

Erosion & sediment control Measures

• Structural Measures:• 1- Designing and implementation

different types of Check dams• 2- Designing Of small earthdam

• 2- Bio mechanical measures on hillside

• 3- biological measures like seedling and plantation of fodder crops

• River engineering• Flood spreading

Flood control & sediment trap by stony check dam

Sediment Trap

River Bank protection

The objectives of work on Hillside are:

• Stabilizing of slopes & erosion control• Rainwater harvesting• Improving vegetation cover• Increasing crop production (fruits and alfalfa)• Improving incomes and welfare of local

people• Improving food security and self sufficiency

Characteristics of WM projects

• Suitable land : Approximately 3.7 mha • Executed : 245000 ha• Planned for 5 years : 1 mha• Type of Activities : Terracing , banquette , • Maine products: Olive, Almond, walnut, apple,

orange, Strawberry , grape, alfalfa• Contribution of People • Having Support of Government

Working on Hillside (terrace)

Working On Hillside

Hillside Rehabilitation (tree plantation & Alfalfa)

Planting on hillside grading works

Example of Watershed Management Measures

نمایی از پخش سیالب در ایستگاه آبخواندری آب باریک بم

نمایی از پوشش گیاهی در ایستگاه پخش سیالب آب باریک بم

Conclusion & recommendation

• Small Dam construction is useful for flood control of heavy storm rainfalls

• Small scale water resource development & Rainwater harvesting techniques are very useful for arid & semi-arid region

• Biological & bio-mechanical measure have high priority because they are multipurpose and have more benefits to local communities and also environment

Tank You for Your Attention