Characterization and impact assessment of water harvesting techniques: A case study of Abreha Atsbeha watershed, Tigray, Ethiopia.

Alem Tadesse1, Tsegazeab Gebrelibanos1, Micheale Geberehiwot1, Atinkut Mezgebu(PhD) 1

1Department of Land resources management and Environmental protection, Mekelle University, Ethiopia

1. Introduction Ethiopian economy is mainly related to agriculture, in which about 85% of the population makes their livelihood. More than 70 million people depend on this sector directly or indirectly. In reverse, the pressure on land is increasing every time forcing farmers to use marginal lands for agriculture production. This leads to land degradation which becomes a crucial problem to the productivity of agricultural lands (FAO, 2003). The effect of land degradation is not only manifested in limiting the productivity of agricultural lands but also in reducing the availability of water holding capacity of the soils(Hailu et al., 2012; Kifle et al., 2014; Tsegay et al., 2010). It impedes the infiltration of water and causes much of it to be lost as runoff. Coupled with land degradation, the low and highly variable rainfall in arid and semi-arid areas place major limitation on agricultural productivity(Barry et al., 2006; Bruins et al., 1986; Bulcock and Jewitt, 2013; Kifle, 2015; Ngigi, 2003; Seleshi et al., 2006).. Even in years of good rainfall, a dry spell during critical periods of crop growth often leads to widespread crop failure or significantly low yield. In addition to the unreliable and highly variable rainfall in the arid and semi-arid parts of the world, low soil fertility is another limiting factor for agricultural production and productivity. In this regard, improving water resources and soil nutrient management will have a paramount importance in enhancing agricultural productivity and ecosystem health in the drylands . In light of this, water harvesting is considered by many as an entry point to enhance agricultural productivity because if water is secured the farmers in the dry areas will be encouraged to maintain the soil fertility.

To mitigate the moisture stress during critical crop growth stages of the rain-fed production and to increase opportunities for irrigated agriculture afterwards, rainfed agriculture in the dryland areas need to be supported by different water harvesting systems (Girmay, 2011). To this end, the Ethiopian government has been involved in the construction of different water harvesting structures for better availability of the scarce water for both rain-fed and irrigated agriculture in Dryland areas. According to Fekadu et al. (2007), the issue of water harvesting was brought on board in Ethiopia since the famine in 1984. Initially it was micro-dams and river diversions which have received top priority. This allowed to boast vegetable production but was limited to areas where there are micro-dams and river diversions. Lessons were also taken from such efforts that it is difficult to construct micro-dams although the initial ambitious plan in Tigray regional state alone, where the study area is found, was to construct 500 micro-dams in ten years.

To alleviate the problem of drought and food insecurity in Tigray, the regional government has embarked on a conservation-based agricultural development strategy since 1991. The major natural resource conservation strategies include soil and water conservation investments on farmland, and the development of water harvesting schemes to store the runoff from catchments for either irrigation, livestock watering or domestic consumption during the dry season. Water harvesting activities are now wide spread in Tigray region with widely recognized success stories in

communities like Abrha weAtsbaha. The Abrha we Atsbaha community has been involved in the construction of various impressive water harvesting structures with a notable impact in the availability of surface and ground water for either supplementary and/or complimentary irrigation. However, the water harvesting structures which were constructed in the Abrha We Atsbaha were not characterized and their performance is not evaluated so far. In this study area, integrated water harvesting practices with main focuses on trapping every drop of rainwater to the forms of groundwater recharging; enhancing soil moistures and reuse for multiple demands were employed. Watershed and natural resource management is not a hobby for these people; it’s a matter of life and death. Prior to the restoration, the runoff and the floodwater leave the catchment eroding the topsoil, washing the nutrients, forming deep gullies with only rocks and barren land remaining behind(Hailu et al., 2012; Kifle et al., 2014; Tsegay et al., 2010). Thus, the community has spent the summer days working on their land and on the upper catchment to solve these problems and thus increase its water harvesting and storage capacity. Now with the ongoing intervention heavy rain has become an opportunity to recharge the groundwater and serving as buffer for dry seasons. The indigenous knowledge of the community takes the largest share of the success that every practice is leading by the community delegates and based on the local knowledge (WAC, 2013). Development of site-specific management strategies by involving farmers and extension workers/development agents is effectively employing. The extension system of the Bureau of Agriculture has also given a greater emphasis for integrated water resources management measures as part of general land management and productivity enhancing practices. However, the physical characteristics of the structures, site suitability of the structures, the impact of integrated watershed management on water availability in the study area with respect to the intervention is not well documented. Thus, the main purposes of the study is, therefore, to appreciate the water harvesting techniques, evaluated and characterized the water harvesting structures and assess their impact on water availability and watershed development of the area.

2. Objective The main objective of the study was to characterize the major water harvesting structures in Abreha Atsbeha and, thus, to evaluate their performance, site stabilities and and effects.

Specific objectiveA. Identify the water harvesting techniques B. Characterization of the major WH structuresC. Site suitability analysis and recommendationsD. Analyzing the impact of the water harvesting techniques on watershed developments

3. Study area descriptionAbreha We Atsbeha is located in Kelte Awelalo wereda (WKA), Northeastern part of Tigray, Ethiopia. The study area is found at 13051’12”N, 39030’28”E and Altitude of 1900-2600 m a.s.l. Abreha We Atsbeha watershed (Figure 1) includes three micro watersheds namely: Weyni, Mendae and Aret with total area of 6,766 ha. These micro watersheds are draining to Suluh River which is the longest and the only perennial river of the study area. The study area is in a long valley running approximately north to south between a sandstone ridge on the west and a basalt ridge on the east (Hailu et al., 2012).

Figure1. Location map of the study area.

The landscape of the study area is mostly hillside and mountainous (45.5%) with 21.5% of medium slope and the rest 34% is categorized as gentle slope where the cultivated land is found (WKA, 2014). Abreha Atsbeha has a total population of 5217(Table1) with 1186 households and 1023 land owner farmers. The female and male population is equivalent with slight increment in female population. The community is well known by Environmental re-engineering in practice and leading model in showing Sustainable Land Management in Tigray.

Table1: Total population of Abreha Atsbeha

S/N Category Population Total Male Female

1. Total Population 2519 2698 52172 House hold leaders 830 356 1186

Sources: (WKA, 2014)

3.1 Story of Abreha Atsbeha

The study area was categorized among the drought-prone areas afflicted by frequent hunger for many years. The rainy season lasts only two to three months (Table 2 and Fig.13). Nevertheless, Strong population growth had caused massive deforestation and overgrazing, leading to land

degradation and an increased vulnerability towards drought and food insecurity. In 1998, the Ethiopian government has decided that the people of the village were to be resettled to a different area. The land had become so barren that the government saw few other choices than to evacuate the valley. One alternative that was offered to the people: If they were to agree and strictly adhere to a new land management plan, carried out by their own workforce, the Ministry of Agriculture would support the restructuring with the help of international donors (Hailu et al., 2012; Kifle et al., 2014).

Since 1998, the community is implementing different methods of sustainable land management such as integrated soil and water storing practices. Gradually, the change has become boldly visible to the community, government and at large to the world that the area is dramatically turning into an array of green environment with sufficient access to water resources. Mr. Gebremichael Gidey, who is the chief of the village, is the initiator of the change and has become a well known man in Ethiopia. He has done what many believed impossible: to save his village from resettlement, thus creating a stimulus for the ecological rehabilitation of large land areas

Since the village has taken up the fight against drought and erosion, many things have changed in Abreha Atsbeha. The groundwater table has risen from 15 meters to 3 meters depth even in the driest season. Nearly all farmers now have their own shallow irrigation well. The community has used a term “water bank” for groundwater ponds to make clear that groundwater is much like a bank account: You have to make a deposit if you want to withdraw later(Hailu et al., 2012; Kifle, 2015)

Today, the villagers owned and harvest water from different water source (Fig.14) and cultivate cereals, vegetables and fruits (Table 6 and 7). They can harvest three times per year – often so much that they can sell the surplus production on the local markets. Everybody in the Community is convinced that nature can’t control man but man can do. Nowadays, the big concern of Abreha Atsbeha is not about more survival but it is about how to own sufficient water and electric power supply so that they can produce more productions that can change their life. The people of Abreha Atsbeha including their leader Mr. Gebremichael were awarded the UN Equator Prize for their outstanding work in 2012. The efforts of the community and the dedication of their leader have not gone unnoticed at national and international arenas. Mekelle University has also extended the recognition for the exemplary leadership and environmental transformation of the community. Abreha Atsbeha is also expecting to host an international event on environmental management practices, in which their success will be a showcase of environmental rehabilitation for others from around the world.

3.2 Agro- ecology The average weather condition of Abreha Atsbeha is categorized relatively as semi-arid agro- ecology with average temperature (T) 210c and average annual rainfall 350-600mm. The

metrological information such as relative humidity (RH) of eight years (2002-2009), Rainfall (RF) of eighteen years (1992-2009), mean temperature of eighteen years (1992-2009) and Evapotranspiration (Et0) (Table 2) were obtained from Wukro meteorological station, which is located about 20 Km from the study area. Almost all the precipitation is falling in two months July (203.66) and August (210mm) (Table 2).

Table2: Mean monthly Average of Metrological data of Abreha Atsbeha

Type Jan. Feb. Mar. Apr. May June July Aug. Sept. Oct. Nov. Dec.

RF (mm) 0.52 2 17.5 30.09

24.59 43.04

203.66 210.55 24.61

5.31 2.85 1.09

T. (0c) 17.68 18.63 20.05 20.99

20.39 21.32

18.77 18.31 19.15

17.87 15.83

15.48

RH (%) 43.38 40.63 41.88 46.13

46.13 45.25

75.88 77.13 48.13

46.75 47.25

43.13

Eto(mm) 4.44 5.20 5.61 5.98 6.09 5.43 3.59 3.79 4.88 5.13 4.45 4.24

Source: Evapotranspiration (Et0) (Tireza et al., 2013)

3.3 Soil characteristicsMost of the soil is very sandy with good infiltration capacity but poor water holding capacity (Hailu et al., 2012). The most important feature of soil is the soil texture. The soil data was collected both from primary observation and examining the soil physical properties using feeling method and /or from secondary data. The study area generally consist of sandy soil texture with a texture composition of 67% of sand, 25% of loamy sand and only 8% of clay texture (WKA, 2014). The soil depth ranges from 1.85 to 2.0m (Tireza et al., 2013). In general, the soil is found comfortable for groundwater recharging and horticultural crop production during irrigation period.

4. Classification of Water Harvesting Techniques Transect walk was made to identify the major physical water harvesting practices implemented in the watershed. Classification of the structures was made based on physical dimension measurement of the structures such as size, volume and physical characteristics of the catchment such as land use, slope, purpose and the way in which water is stored (reservoir, soil, container etc.). Dimensions were measured using tape meter and graduated stick. The major water harvesting structures and storage techniques was identified by direct measurement and observation, group discussions with experts and key leaders of the community such as watershed commutes, chief leader, youth associations and farmers. The WHT are categorized in to eight based on structures (Table 3) and in to three based on their slope and purpose (Fig. 12): (1) on the sloppy area –runoff reduction, (2) The middle slops –for enhancing infiltration and soil moisture and (3) Gentle slopes- water harvesting for different utilizations mainly for irrigation and domestic water supply. Up on the mountain slopes, stone bunds and bench terraces were constructed and percolation trenches were excavated in order to stop the massive erosion and to recharge the groundwater. Trees and grasses were planted to stabilize the soil. At the bottom hill of these mountains, people dug shallow wells and so call discharge zone. This classification is supported with the general approaches recommended by (Desta, 2010; Kifle, 2015).

4.1 Physical Characteristics To select reliable WHTs which could be sustainable and effective under local circumstances, it is always necessary to understand the basic characteristics of the different WHTs (Bulcock and Jewitt, 2013; Lasage and Verburg, 2015). To conduct the characterization, this study considered major

factors determining the applicability and accessibility of water harvesting techniques. The water harvesting structures should technically be applicable under physical circumstances in the field. Field preconditions- the data such as the precipitation, the slope of terrain, the soil properties, geology and land use land cover was collected both from primary (observation, measurements, individual and group discussion) and secondary from annual report of the wereda (WKA,2014), documentation of the Study area (AWA, 2015). Characteristics of the structure- storage capacity, and infiltration capacity, purpose of the structures, acceptability, and cost per headwork was determined and analyzed. To understand the physical characteristics of the major WHT (Table 3) detailed measurements including their specific location was carried out using tap meter and GPS.

4.1.1 BENCH TERRACE Construction of bench terraces is the most important WHT employed in the study area (Fig. 2). The main purpose was to reduce the slope length, reduce runoff and soil erosion, to enhance soil moisture and thus increase crop and forge production on the pieces of plots (Fig. 2 (right). It was also observed that the structures have great impact in rehabilitation of the degraded land and restoration of the hillsides of the watershed. Bench terrace are the most effective in hillsides with the slope 15%- 40%. The average width 20-140cm, height 65 -170cm and spacing between rows from 3.2m in areas very steeply slope to 15.5m in area with slopes less than 15%(Table 3).

Figure 2: Bench Terraces in Abreha Atsbeha (Author, 2015)

The designs are based on local knowledge’s “Non-engineered designs”. Of course, Bureau of agriculture provided them supervisors on specifications of the designs. However, this study investigated that the demission has slight change. This study used information from 8 samples and the characteristics of the structure is presented in Table 3. The dimensions that provided from the Bureau of agriculture (AWA, 2015) are basement width-1.6m, top width-50 cm, height-1.5m and spacing between consecutive structures 3-6m depending on soil type and slope. These dimensions are blanket values, which didn’t consider other factors such as geological formation of the command area. What really impressed in this area is that the creativity of the community that the dimension varies as the formation varies.

4.1.2. STONE BUNDSStone bunds are constructed following the counter of the micro-watershed. The main purpose is to reduce the slope length, slow down and filter runoff, thereby increasing infiltration and capturing sediment (Seleshi et al., 2009). The water and sediment harvested lead directly to improve the soil depth and fertility and thus to motivate tree plantation and production. The technique is recommended in sites of small-scale application on farmer’s fields with a slope 2-5% and adequate supply of local materials such as stones. However, in Aberha Atsbeha the technique is modified that

it can be well adapted in any type of land uses even in areas of hillsides with the slope up to 40 % (Table 5).

Figure 3: Stone bunds in: Bush land (Left) and Bare land (right)

Although it is simple to construct, a minimum bund height of 65 cm is recommended, with a base width of 60–80 cm (Fig.3) is recommended. The bund contains a shallow trench on the upper side of 15–30cm depth, which helps adequately to trap runoff and sediments. It is important that the construction details incorporate a mixture of large and small stones. The bunds are constructed with smaller stones placed upside of the larger ones constructed as retaining wall to facilitate rapid siltation. Average Bund spacing of 12.75m was measured. The spacing between bunds ranges between 8.7(slope up to 40%) and 16m (slope less than 15%) depending on the slope, stone and labour available. As the slope increases the spacing in-between decreases.

4.1.3. STONE BUNDS WITH TRENCH

It is a construction of stones embankment at the downside and digging of the trench at the upper side of the stone bunds to form earth embankment following a contour. The physical description of the structures is that a foundation up to 20 cm is digging and stone wall is constructed with height 50-70cm, bottom width 50-80 cm and the spacing between rows 20-23m. Series of trenches are then constructed along the contour of the stone bunds with depth of 40cm, width of 65-70cm and spacing in-between of 50cm (Table). The purpose is usually to decrease soil erosion, increase moisture harvesting, decrease slope length and thus reduce runoff velocity and increase productivity per unit area. In addition to their physical characteristics, it is observed that their effectiveness is high areas with a slope 0-30% and where fodder trees are planting and integrate with other biological measures. In the study area, the structures are most common practices in cultivated land and hillsides of the catchment. After the interventions are being practiced, the watershed is now growing natural grasses and vegetation, minimizing desertification, recharging the ground water and in general improving the local climate.

Figure 4: Stone bunds with trench in Abreha Atsbeha watershed (Author, 2015)

4.1.4 SOIL BUND WITH TRENCHSoil bunds with deep trenches are ridges and ditches made of soil dug across the contour slope of the catchment (Fig. 5). It is constructed for the purpose of preventing run-off, reduce soil erosion, enhancing of soil moisture and hereby improve productivity. This technique is well suited in areas of both cultivated and grazing lands with slopes (0-5%). Its construction is very simple that it always carried out by the local knowledge of the community. The width, depth, length, and spacing with in trench and in between bunds determines based on the soil, slope and land use (Table 5). For instance, if the land use is cultivated area, the size of deep trench is 50cm (depth) x300cm (length) x50cm (width). While in grazing lands the size of one deep trench is 100cm (width) X 50cm (depth) X 300cm (length). The standard of the spacing in between trenches is 100c though the dimensions can be unstable after a while. The spacing between rows of contour bunds is ranged from 20.5-22m. (Table 3).

Figure 5: Soil Bund with deep trench: a) cultivated land with deep trench; B) Deep trench in grazing land while contained water; and c) cascaded deep trenches while ready to contain water.

Since the soil is sandy and soil depth is high, deep trenches have the ability to store high amount of harvested rainwater and infiltrate quickly. According to Terizea et.el 2013, an individual structure is capable to capture more than 765.85m3 of rainwater every year.

4.1.5 SEMI- CIRCULAR STONE BUNDS

Semi-circular bunds with stone embankments are in the shape of a semi-circle with the tips of the bunds on the contour (Fig. 6). Semi-circular bunds are used mainly for rangeland and bush lands rehabilitation. It also services as ground water recharge. The technique also used for growing trees and shrubs and, in some cases, has been used for growing fruit trees.

Figure 6: Semi-circular Bunds with Acacia Tree

The technique is suitable for slopes of less 5% and consists of a series of small semi-circular bunds with radii of 3-6 meters. The size of the radii varies with area of upper catchment where the runoff is generating and, of course, the slope. The semi-circular bunds are constructed in staggered lines with overflow producing catchments between structures. The measured dimensions of bund of the study area are: height is 25cm with side slopes of 1:1 which result in a base width of 75 cm at a selected top width of 25 cm (Table 3) The tips of each bund are set on the contour, and the distance between the tips of adjacent bunds in the same row is 3 meters. Bunds in the row below are staggered, thus allowing the collection of runoff from the area between the bunds above. The distance between the two rows, from the base of bunds in the first line to tips of bunds in the second, is 3m. At this spacing 70–75 bunds per hectare are required (Seleshi et al., 2009)

4.1.6 Percolation pond In Abreha Atsebha more than 73 cascaded percolation ponds are constructed. Their significance in raising the water table (In general to increase access to water) is believed to be more than any other WH structures of the study area. The main characteristic of the percolation ponds is that, as their name implies, they are intended to impound and increase the residence time of harvested floodwater (Fig. 6 right). These series ponds (Fig. 6 left) are usually made up of earth embankments. The structures are used to slow down and store floodwater-which has been generated from the hillside of the catchment with high velocity and erodability, and accumulate of sediments. Their ultimate goal is to recharge the ground water and later reuse for irrigation and other domestic purposes as groundwater sources. On average each percolation pond has the capacity to contain and infiltrate more than 5,025 m3 of rainwater per year (Tireza et al., 2013). The physical characteristic of the pond was measured using surveying and mapping instruments and observation. On average the volume of the ponds varies 956-1882m3. Though the ponds have accumulated high amount sediments, an infiltration pond with maximum depth of 3.9 meters was observed. The structures are constructed using machines with the help of Bureau of Agriculture.

Figure 6: cascaded infiltration ponds: a) schematic map of typical ponds B) series ponds while store water(Kifle, 2015)

4.1.7 CHECK DAMS

In Abreha Atsbeha next to shallow wells check dams have been covering large portion of for irrigation lands (Fig.14). The report (WKA, 2014) has documented about 55 check dams. The structures are successive and constructed along the different watercourses of the catchment all the way down the hill. The community has constructed check dams with bundles of stones and gabions cemented with mud that are also used to collect portion of the running water to help recharge the ground water down the watershed. To protect the structure not to crumble down under the force of the flooding, other similar barriers with spacing 35 to 40 meters in-between has also been constructed up the hill. Spillways (Fig. 8 (a)) have left to the side of the pond that would allow the water to continue flowing out and down after a certain level of water is collected in the pond. All the structures with similar physical characteristics have constructed mainly for three purposes. 1) Collect the floodwater; 2) reduce the speed and thus other structures down the catchment area will not be threatened as much as they would without such kind of intervention and 3) accumulate sediments.

A. The community works on a check dam B) Impact of check dams on Gully rehabilitation

C) Downstream side of the check dams D) Check dams while store water

Figure 8: Check Dams in Aberha Atsbeha: Prevents erosion and enables irrigation in the dry season

Table 3: Observed physical water harvesting dimensions (source Author)WHT Slop

e Land Use Dimension Avera

ge Minimum

Maximum

Stone Bund With Trench

Cultivated Height Of Stone Bund (cm)

61.25 50 70

Width Of Stone Bund (cm)

80 80 80

Spacing Between Rows (m)

21.75 21 23

Depth Of Trench (cm) 40 40 40Width Of Trench (cm) 68.75 65 70Spacing Between Trenches (cm)

50 50 50

Length (Cm) 287.5 270 300 Stone Bund Bush Land Height (Cm) 65 50 75

Width(Cm) 74.28 60 80Spacing (m) 12.76 8.7 16

Soil Bund With Trench

4 Cultivated Width Of Trench (cm) 105 100 110Depth Of Trench (cm) 55 50 60Length of Trench(cm) 2.5 2 3Spacing between Trenches (m)

1 1 1

Spacing Between Rows (m)

21.25 20.5 22

Bench Terrace 40 Hillside Height (cm) 122.08

65 170

Width(cm) 65.83 20 140Spacing (m) 8.43 3.6 15.5

Bench Terrace 30 Bare Land and Hillside

Height (cm) 144.37

110 170

Width(cm) 91.25 70 120Spacing (m) 5.24 3.2 12.4

Check Dam Drainages Height (m) 1.87 1 2.4Crest Width (m) 0.9 0.8 1.1Basement Width (m) 4.01 2.4 8.5Length of the Crest (m) 20.95 15 27.8Free Board (m) 1.01 0.75 1.2

Shallow Wells 4 Cultivated Diameter : Top (m) 6.74 5.2 8.2Diameter : Bottom 4.5 3 6Minimum Depth Of Water (cm)

95.3 30 250

Depth Of Well (m) 5.11 3 8Maximum Water Depth (m)

3.35 2.7 5

The technology is very sound that the community is now able to tap ground water at a depth of 3 to 4 meters in exactly the same places where the water table used to be deeper than 15 meters and with low yield. Every check dam has the ability to harvest annually about 5,012.6m3 of rainwater (Tireza et al., 2013). The check dams are also serving as source of income for the community. The youth associations of the watershed are used to collect 560m3-640m3volume of sand every year.

4.1.8 Diversion Head It was mentioned earlier that every drop of water of the watershed is used in integrated approach. Like other water harvesting techniques river diversion works have also played significant role. Two structures are constructed across the water course of Suluh River with a total length of 3 km lined canal (1500*2 =3km ) distance and contribute an area of 57.75ha irrigated lands.

Figure 9. River diversion structure

Table 4: Standards of Physical characteristics of Water harvesting techniques

Water harvesting structures Dimension Diameter

Spacing

H BW TW

Depth Length Bottom Top

Deep trench 50 50 100 300Stone bund 65 80 50Bench terrace 150 160 50 -- 300-600Stone bund with Trench

Stone bund 50-70

40 400-600

Trench Farm land

100 50 50 300 50

Bare land

100 100 100 300 100

Earthen bund with Trench

Earthen Bund

60 100-120

30 22m

Trench 100 50 50 300 50

Semicircular bund 20-50

70-100

3-6m 3m

Hand dug wells - - - 8 3 8Machine dug wells 10 6 8Hand pump wells 10 6 8

N.B. H= height; TW= top width and BW= bottom width

sources: (AWA, 2015)

4.1.9 HAND DUG WELLS Around 388 hand dug wells were dug out along this catchment area where people are carrying out irrigation practices using the waters from the wells. However, due to ground water overexploitation some of the wells especially the wells on the upper catchment are being dried and currently only 320 wells are functional. Of these, 300 wells are serving for irrigation and the other 20 for domestic water supply. The wells are classified in to three groups based on their construction: (1) unlined (2) lined and semi lined with masonry only and (3) lined both masonry and cement. Measurements were taken from 15 shallow wells. Of theses, 90 % lined with Masonry (Fig. 10 (B and C) and 5% lined with Cement and Masonry (D) while less than 10% of the observed wells are unlined (A).

a) Unlined shallow well B) Lined with Masonry

C) Lined with masonry D) Lined with masonry and Cement

Figure 10: Different forms shallow hand dug wells in Abreha Astbeh (Author, 2015)

According Teriza et al, 2014, every hand dug well has the ability to produce on average 14,795m3 water per annum. Fig.10 (C) with the mark white color and Fig.10 (D) Dark color on the sides of the wells are indicators of how the water stored rises in to maximum depth (up to 7m or 2-3m below the surface) during September - December. The difference is visible that before the intervention (1998GC) of different water harvesting techniques, the ground water table was 15cm ( Kifle et al, 2013). It also observed and reported (AWA, 2015) that all functional wells yield water throughout the year with minimum depth of 30cm-115cm (Table 4), which is occurred in dry season (April-May). Though the groundwater potential is rich

enough, the communities have concerns on the balance of demand-supply water. To solve these problems solutions have suggested that:

Rules that must fix the amount of wells to be owned by individuals and the distance between wells too should be stated, i.e., currently every farmer of the community can dug wells as many as possible.

Because the population is increasing from time to time, as per the group discussion, the demand for water increasing and the existing shallow wells don’t satisfy the needs. Hence, constructing deep boreholes should be a must.

In General, the basic interest of the community is maximizing their productivity by reducing the amount of hand dug wells and optimizing the depth of wells to be dug.

4.2 Soico- Economic characteristics Resources necessity for construction versus existing water harvesting structures was assessed. In this case the investment costs, raw materials, labor (both skill and local), technical complexity, policy direction, governance of the watershed and maintenance are the major parameters that which were covered in this study. The other and most important is that the acceptability and lifetime of the structures – this was also be studied by conducting semi-structured Questioners. The raw materials such as stones are supplied from the bedrocks of the watershed using labours methods: the men crashing using hammers and carried out by females to the construction sites (Fig.11). However, materials such as Gabion and Cements are supplied from the government (Bureau of Agriculture Development and Agricultural Extension).

Aba Hawi (the chief leader of the development) was full of enthusiasm and energy to explain the hurdles and the great efforts the community. He has to make following the exemplary leadership of a strong and dedicated natural leader of exceptional caliber. Aba Hawi has never been to school or received any formal education of hydrology or natural resource management type. He believes the success is based on the unreserved effort of the community. However, the community believes that people of the community was already there for centuries rather the people believe that the mystery is from the exemplary leadership. In Abreha Astbeha, gender equity is exercising more than the simple Democratic words. During the group discussion, the participants (particularly the female participants) including the chief leader underlined that about70-80% of the success counts to the female population of the community. There is no question that each and every benefit from the watershed especially from the communal properties equally distributed to the community members.

a) Community participation in construction material collection

C) Check Dam maintenance D. group discussion with community members

Figure 11: community participation in Abreha- Atsbeha( Auther, 2015)

5 Site suitability analysis In terms of irrigation shallow wells are listed among the common and best performing of water harvesting techniques of the study area. A single structure can be averagely covers up to 2ha of irrigation lands. Next to shallow wells and check dams and river diversions have also played massive roles in irrigation development of the study area that a sing diversion head has the potential to irrigate an area of more than 28 hectares of lands. The water sources are located lower than the commend areas and mainly beneath the ground surfaces, thus almost every farmer is using generators (motor pumps, and /or treadle pumps) to irrigate their farmlands.

The spacing between all water harvesting techniques is dependent on slope, soil depth and soil texture of the particular land uses. For example, stone bunds with deep trenches are constructed at hill land with slope reaches up to 40% and serving the watershed effectively. The designs also constructed at farmlands while slope varies up to 5%. The construction in the farmland is found feasible if the martial are supposed necessarily existed otherwise soil bunds with deep trenches are served as other options in cultivated lands and in slopes less than 5%.

The estimation of costs per head was slightly difficult that almost all the works were done as part of free services of the community (a minimum of 20 days every year). However, the average costs per volume (1m3) and or per a unit length (1m) have been estimated by combing

the labour cost (daily laborer) and material cost (masonry, cement and Gabion). For entrance, to construct 3m length of stone bund with trench three laborers per day is required. This means that labour cost is 3*$4=$12 and the cost of masonry per unit volume is (if the volume of masonry for three meters long, 70cm height, 1.6m bottom width and 50cm top width is 2.73m3 and the unite cost is $6.25) 2.73*$6.25=17.0625. The unite price is, therefore, estimated to be $5.687 per meter work of both stone bund and the deep trench along.

Table 5: site suitability analysis of water harvesting techniques

s/n

Name Land use Slope %

Purpose Construction Cost per head (USD)

1 Deep Trench Any 0-5 Moisture conservationGround water recharge

$3.5/ m3

volume

2 Stone Bund Hillside 15-40%

Land rehabilitationReducing slopeReducing runoff risks

$3.5/ m3

volume

3 Bench Terrace Hillside 25-30 Fruit production Land rehabilitation Runoff reduction Groundwater recharge

$14.4/m3

volume

4 Stone Bund with Trench

Hillside

Farm land

0-30 Reducing runoff Moisture conservation

$5.687/m length

5 Earthen Bund with trench

Cultivated land

Bush land

0-5 Moisture conservation Reducing runoff Reducing soil erosion

$3.5/ m3

volume

6 Semicircular Bund

Bush lands 0-5% Groundwater recharge Runoff reduction

$3.5/ m3

volume

7 Check Dams Along streams

Any Irrigation Gully rehabilitation Erosion

$4000/head

protection Mining

8 Infiltration pond Bare lands 0-5 Ground water recharge

Unknown *

9 Hand dug wells Cultivated land

0-5 Irrigation and domestic water supply

$2000-6000/head

11 Hand pump wells

Any 0-15 Water supply $6000/head

*Percolation ponds are constructed by government (source: Author, 2015)

Based on the observation, measurements and the community recommendations (local knowledge) the site suitability analysis has been summarized in Table 5. Since the soil is sandy soil deep trench, check dams and percolation ponds are the most important and effective water harvesting structures in this study area. If the structures classified based on slop of the catchment and purposes (Fig. 12), soil and water conservation strictures such as stone bunds and bench terraces are found very effective in the upper catchment (slopes up to 25-40%).

Figure 12: Abreha-Atsbeha Schematic Approaches for Watershed Management in(Kifle, 2015)

The structure is capable enough to reduce slope length and thus increases infiltration and decrease runoff so as decreases soil erosion and flood risks at the downstream of the watershed. Check dam, percolation ponds, stone bunds with trenches are very important at the middle slope (5-25%) of the watershed. The main aim of being constructing these structures is very important for two things: 1) to trap the water that comes from hillside of the watershed with high potential to make disasters at the cultivated lands 2) It allows the water to store for long period of time and recharge the ground water. At gentile slops (0-5%) especially along and within cultivated lands and grasslands, deep trench and Semi-circular bunds are found most common practices. If the impact of all the aforementioned soil and water harvesting techniques are summing up, they significantly changed the watershed development with two main tasks 1) Reduce risk of runoff/ erosion at downstream/flood plains and sediment deposition. 2) Increases access to water everybody from different perspectives through ground recharge.

6 The Impact of water harvesting techniques The impact was assessed using observations, individual and group discussions, secondary data such as reports of the woreda (KAW, 2014), the study area (AWA, 2015) and literatures. The impact measurement and analysis was carried out considering the sectors of Agricultural production (animal and crop production); accesses to water - the amount of water supply for domestic, irrigation and sanitation; and Environmental re-engineering – land use and land cover changes, land rehabilitation such as gully rehabilitation, aforestation and soil and water conservation. This study also considered the impact of WHTs on groundwater recharge (the main sources of water in the study area)-the amount of water that infiltrates due to in- sue water harvesting structures was determined from the water balance equation and the change in depth to surface by direct measurements.

6.1 Crop production Crop production of Abreha Atsbeha is manly from three seasons: one rainfed (Summer: from June – October) and twice from irrigation agriculture (October- February and March –June). The most common type of crops, vegetables and fruits under rainfed and irrigation, and for each crop the area of cultivated land, yield per year and yield per hectare are summarized in Tables 6&7(KAW, 2014). Some crops such as Maize, Teff, Barley and Wheat are commonly harvested in both types of productions (Table 6). Though the production of Teff (13.75q/ha) is relatively lower than wheat, it is the most wanted and highly preferable crop in the study area. However, in Irrigation agriculture the community gives priority to Maize production and also covers the largest irrigated land as well as large production.

Table 6: Cereal Production of Abreha Atsbeha : cultivated land and yield in hectare SN

Crop type

Rain fed Irrigation Area coverage (ha)

Yield(q)

Yield per ha

Area coverage (ha)

Yield(q)

Yield per ha

1 Wheat 193.5 7132.56 36.86 13 448.5 34.52 Barley 84.75 2415.37 28.5 21.5 354.8 6.5

3 Teff 135.25 1859.25 13.75 39 468 124 Hanfets 48.5 1406.5 29 -- -- --5 Millet 57.5 1265 22 26.5 715 26.986 Finger

millet 22.5 427.5 19 -- -- --

7 Maize 11.75 313.5 26.68 103 3178.5 30.868 Been 4.25 63.25 14.88 14.3 203.1 14.2

Source: Werda kilteawlaelo wereda, 2014

Figure 13: Agricultural production calendar versus rainfall of Abreha Atsbeha (GIZ, 2010).

The rainy season of Abraha Atsbeha is categorized in two namely the dry season September- May and wet season from June-August (Fig. 13). The planting and harvesting time is, therefore, depending on the rainfall occurrence-mostly from June to November. Since the cropping calendar is developed in 2010 GC, the irrigation calendar is not well noticed.

6.1.1 Irrigation development In Abreha Atsbeha irrigation is becoming the common practice. More than 1023 farmers are employing irrigation for their cereal, bean, vegetation and fruit production. Irrigation is practicing twice in a year and from 858 WHT an area of 460ha is covered every year (WKA, 2013). Irrigation practices such as furrow for vegetables and Corns, border for cereals and Beans, point irrigation for fruits are the most common in the study area. The water sources for

irrigation are mainly (57%) from ground water using shallow hand dug wells (3-9m depth), 20% from check dams, 13% diversion heads and 10% from ponds (Fig. 14). During the rainfed agriculture, because the soil is sandy soils, spate irrigation is also used, as technique to supplement while the frequency and amount of the rainfall is supposed insufficient.

Shallow wells; 320

Check dams; 55Diversion ; 2Ponds ; 88

Percolation ponds ; 393

Shallow wells57%

Check dams20%

Diversion

head13%

Ponds (pasca )10%

Figure 14: pie diagram of functional water harvesting structures (Left) and sources of water for irrigation (Right)

It also understood that vegetables and fruit trees have no significant production during summer season. During irrigation period tomato (210.3q/ha) and pepper (112q/ha) from vegetables and Guava (317q/ha) from fruit trees cover the largest share of the production and also served as the largest income generating commodities for the community (Table 7).

Table 7: Irrigation Coverage and Production of Vegetables and Fruits s/n

Vegetables FruitsType Area

(ha)Yield(q)

Yield per ha

Type Area (ha)

Yield(q)

Yield per ha

1 Tomato 172 36173

210.3 Guava 10.25

3250 317.07

2 Pepper 97.5 11895

122 Orange 12 1251 104.25

3 Carrot 8 1920 240 Lemon 5 1040 2084 Cabbag

e 11.5 1495 130 Avocad

o 5 880 176

5 Salad 10 1200 120 Papaya 1 530 5306 Garlic 11.5 1035 90 Mango 5 196.7

539.35

7 Onion 6.5 715 110Source:(WKA, 2014)

It is very interesting that in areas that were bared and degraded land (1341.36 ha) 15years ago is in such ridiculously progressing watershed in every direction. In this study, It was mentioned many times that this is not because of the gift of the nature rather it is because of tireless effort of the community. Fig.11 and15 are evidences that every activity in the community is labour intensive. For instance, more than 57 % of the irrigation is from shallow walls, Fig. 15(C) shows how the individuals irrigate their farmlands using treadle pump.

Fig.15 (D) also shows, though the community have started producing of surpluses production, their access to market is challenging that they use local transportation to collect the production and reach the markets.

a) Fruit trees (Mango apple) C) Treadle water lifting for irrigation

B) Vegetation (Tomato and Pepper) D) Means of Transportation

Figure 15; Irrigation practices of Abreha Atsbeha (Author, 2015)

6.2 Livestock Production The watershed of Abreha Atsbeha like other production of the watershed development, production of livestock is significantly promising and used major sources of generating incomes. In the watershed around 1500 ha of the hillsides are perfected for land rehabilitations as “Area Closures” and thus serving for forge and grass production for the livestock fed and also for honeybee production for the youth associations. The production is now emerging when it compares to the years water was scare even for domestic water supply. The total livestock production of the watershed reaches more than 8784 heads and 1490 Beehives.

Cattle Sheep Goat Poultry Camel Donkey Beehive

3908

1177 1077896

50

16761490

Figure 16: Livestock production of Abreha Atsbeha (WKA, 2014)

The major livestock productions of the study area are Cattle, Donkey, Sheep and Goats (Fig.16). Cattle and Donkey have dominated the production because cattle are using for ploughing their agriculture lands and Donkey also used for transportation. Besides, now a day, because of the over greening of the catchment honeybee production is becoming the third dominant livestock production of the study area. There is also a central protected grazing area with a rich biodiversity that is also a wetland in the rainy season (Hailu et al., 2012).

6.3 Domestic water supply Since the implementations of different interventions of water harvesting technologies the total water supply converge of the watershed is recorded about 96% (WKA, 2014) with a travel time to water sources of 25-30minutes. The average daily domestic water supply per household of the watershed is estimated to be 100 litter/ Day. The source of water supply is 100% from ground water through shallow hand dug wells (56%), shallow boreholes (30%) and the other 14% from springs and deep wells (Fig.17).

Hand dug wells; 17

Shallow borehole; 9

Deep well; 2 Spring ; 2

Figure 17: Water resources potential of Abreha Atsebhas (WKA, 2014)

Because the water uses for all demands is from ground water and the geological water bearing formation is sandstone, obviously, the water is expected with a good quality. However, the people of the community have complaints on the quality and quantity during April-June (the hottest period of the year). The depth is very shallow (maximum 10m) and the population increase from time to time. Besides, the soil is sandy which is susceptible to evapotranspiration. Due to these combined effects the water inside the shallow wells are usually decreasing its quality and quantity.

6.4 Land use and land cover changeThe study area consist three watersheds namely Mendae, Weyni and Aret. The Abreha Atsbeha watershed is classified in to six land uses namely degraded land, Grazing Land, Cultivated Land, Bush land, Area Closure and irrigation lands. The land use and land cover changes for the last 21 years has been determined using ArcGIS (Fig. 18).

In areas with intensive and sound intervention, the land use land cover change is expecting to be positive. Fig.18 also confirms the same result that before intervention (1984G.C.) the degraded land (34%), cultivated land (32%) and bush land (32%) were the three major land uses with only 2% of grazing lands.

Figure18. Land use land cover change map of Abreha Atsbeha from 1984 (left) to 2010 (right)

After the intervention has been carried out for 12 year (1998-2010), the land use land cover changes is dramatically changed and new land uses such as area closure and irrigation are introduced in hundreds of hectares. The land use land cover changes which were achieved in 12 years of intervention has been estimated as degraded land (2%), cultivated land (33%), bush land (40%), area closure 15%, irrigation land (8%) and grazing land stays almost steady. For most scholars this could be a dream but it is real that in Abreha Atsbeha watershed everything is possible. The degraded land change is unbelievable. It has been reduced from33% to now 2%. The change accounts in to cultivated land, Bush land, Irrigated land and Area closures (Fig. 18 and Fig. 19).

Dergraded Land Grazing Land Cultivated Land Bush Land Area Clusure Irrigation Land 0

500

1000

1500

20001341.36

88.38

1311.21 1408.5

106.92 69.59

1349.191630

622.89317

1984 2010

Figure 19: Land use- land cover changes before and after the intervention in hectare.

Generally, due the intervention of different soil and water harvesting structures, land degradation is almost 100% is controlled. The watershed is becoming ever greening environment and best example for the world. With 12 years age, in Abreha Atsbeha, all degraded land are rehabilitated and the rehabilitate land are also utilized for different purposes such as irrigation, sources for sands for building constriction, area closure, aforestation and thus serves for honeybee production. The catchment is also a center for wildlife production. It gives also great impression the relative increment of bush land is greater than cultivated land and every year the area coverage of irrigation land and area closures also promising that in the mean future the areas could be center for truism (wild animals).

6.5 HydrolologyObviously, as water harvesting techniques implemented and water is harvesting from different sources such as shallow pond, check domes, diversion heads and infiltration ponds, the water balance of the catchment has showed dynamic change . The input component of the catchment is precipitation and the output components are actual evapotranspiration and runoff. Using the water balance equation the amount of water that infiltrated into the ground water was calculated.

P-AET- Q = GWR

Where, P is precipitation (m3); Q is surface runoff (m3); AET is actual evapotranspiration (m3); and GWR is groundwater recharge (m3).

Table 8: Annual Water Balance Before and After Intervention: Mendae Micro catchment

Water Balance Components Before Intervention After Intervention Precipitation (m3) 5, 867, 346 5, 867, 346Actual Evapotranspiration (m3) 4, 206, 149.41 4, 206, 149.41Surface Runoff (m3) 1,577,167m3 1,008,821.4Groundwater recharge (m3) 84, 029.59 652, 375.19

Sources: Tireza et.al, 2013.

There is 9.69 % decrease in surface runoff after the intervention. This decrease in the runoff is mainly due to the intervention of integrated soil and water harvesting measures that create an opportunity for the water that was used to leave the area as a overland flow to percolate and recharge the groundwater. The volume of water that percolates down and join the groundwater after the intervention was found to be 652, 375.19 m3whichis11.12 % of the mean annual rainfall of the catchment. Surface runoff that are generated from the upper bush land and bare land that has a total amount of 465, 031.02 m3 is captured by the various physical conservation structures which are constructed at the foot hillsides the catchment. This amount is an additional amount that percolates deep into the ground. As a result, the actual groundwater recharge after the intervention was found to be 1, 117, 406.21 m3 (19.04 % of the mean annual rainfall of the catchment). A green stripe indicates where the groundwater has risen significantly. The presence of the water table is indicated by the large fig and Acacia/Faidherbia albida trees scattered throughout the valley (Fig. 20)

Figure 20: Typical indicator of existing ground water

6.6 Land RehabilitationIt was reported that before 1998 the land degradation, deforestation and drought of the study area was among the severest areas in Ethiopia particularly in Tigray (Kifle, 2015; Seleshi et al., 2006; Tsegay et al., 2010; WAC, 2013). Unless the watershed is treated and special attention has been drawn, the phenomenon is highly susceptible for erosion and gully formation as the soil texture is sandy and more than 48% of the watershed is hillsides. The gullies were extended up to 11m deep below the ground surface (Fig. 21(left)). However, after intensive commitments of the community the gullies are now rehabilitated into dynamic changes. All the activities mentioned under Article 4 have greatly affected the watershed. Restoration of natural vegetations, planting fodders, and protection existing shrubs and trees have changed the watershed from bared to ever green environment. Now, almost all the gully erosions have been controlled and the streambeds are becoming as a center for biodiversity.

Before intervention after intervention Figure 21: Impact of WHT on successful gully rehabilitation (GIZ, 2010)

7 Conclusion and Recommendations In Abreha Atsbeha farmers had detailed understanding of how conservation structures and vegetation in the upper part of the watersheds contribute to the amount of ground water recharged in the lower part of the catchment. They explained conservation and re-greening activities in terms of what they call “the water bank”. After the implementation of integrated water harvesting structures in the catchment, every drop of rainfall is supposed to be at the catchment either on the surface or underground. The runoff generated from the different land uses is reduced and thus the depth of groundwater is increased to the level of three (3) meter below the ground surface. Since the interventions back to 1998, the availability of the ground water in the catchment is increased by 13meters. This result is achieved due to the strong commitments and extraordinary exemplary leadership of the community.

Because of suitable average annual rainfall (350-600mm) of the watershed, the physical characteristics of the water harvesting interventions are found very effective in storing water and enhancing soil moisture, reducing erosion and flood risks to the downstream and generally increasing the agricultural production and environmental reengineering of the catchments. The hand dug wells that are found drilled in the downstream side of the catchment are the evidences that groundwater potential is rich. Currently, farmers are utilizing this water throughout the year for complimentary irrigation during dry season and supplementary irrigation in the rainy season where the rain gets scarcity. The structures employed in the catchment are classified into three implementing positions: 1) Recharging area where the slope of the catchment is high; 2) Intermediate area where the structures

further allow to store floodwater and filtrate and 3) Discharging areas where water is using for different activities such as irrigation and domestic purposes (Fig. 12)

The study area is characterized by high intensity of rainfall during two months which can produce high surface runoff. Thus, this study suggested that effective maintenance and design improvement of the physical water harvesting structures are continuously required. For better results and production land suitability evaluation should be carried out before the implementation of different management intervention. The soil is sandy and less fertile. Thus, the community eagerly needs area specific soil- nutrient study for better fertilizer applications. Though there is enough potential of ground water, the water demand for irrigation and other purposes with the existing water supply are found imbalance. Hence, deep boreholes together with electric power device to lift the water to the command areas are very important for the next few years to implement.

Generally, in order to maintain the continuity of proper and integrated watershed management, all stake holders should give due attention and provide the required. In Abreha Atsbeha, despite numerous challenges (less soil fertility, erratic rainfall, high erosion and degraded lands) through integrated community owned watershed development and management food security; and climate change and drought resilient environment is developed and can be an example for others to follow. The community strongly believes on the proverb “A man who has water has everything” that, today, everybody has enough resource for their life to change both in food and nutrition security.

8 ReferencesAWA, 2015, Annul poster of Abreha Atsbeha watershed: Abreha Atsbeha Farmers' Training

Center,Tigray , Ethiopia.Barry, B., Olaleye, A., and Adeoti, A., 2006, Soil Water Conversion and Rainwater Harvesting

Technologies in the semi-arid zone of sub-Saharan Africa. : GRID-IPTRID, v. Issue 24.Bruins, H., Evanari, M., and Nessler, U., 1986, Rainwater harvesting agriculture for food production in

arid zones: the challenge of the African famine. : Applied Geography, v. 6, no. 1, p. 13-33.Bulcock, L. M., and Jewitt, G. P. W., 2013, Key physical characteristics used to assess water harvesting

suitability: Physics and Chemistry of the Earth, v. 66 p. 89-100.Cluff, C. B., Engineering aspects of water harvesting at the University of Arizona. , in Proceedings

Proceedings of the water harvesting symposium, March 26-28, Phoenix, Arizona, 1978, Volume 27-39. .

Desta, 2010, General apporches of watershed managment.FAO, 2003, A perspective on water control in southern Africa: Support to regional investment

initiatives. , Land and Water Discussion Paper 1: Rome, Italy., Food and Agriculture Organization of the United Nations.

GIZ, 2010, Factsheet of Abreha-We-Atsbeha Watershed In Kelte Awlaelo Woreda, Tigray Region, Ethiopia in Factsheet, ed., GIZ: Mekelle, Ethiopia

Hailu, A., Yohannes, G., and Sue, E., 2012, SOME EXAMPLES OF BEST PRACTICES BY SMALLHOLDER FARMERS IN ETHIOPIA, Addis Ababa, Ethiopia, Best Practice Association (BPA) and Institute for Sustainable Development (ISD), v. 1, 177 p.:

Kifle, W., 2015, Water Harvesting and Climate Change Adaptation; the experience of Tigray region In Ethiopia.: Mekelle, Ethiopia.

Kifle, W., Diego, G.-L. P., Frank, V. S., Martin, V. B., and A., M., 2014, Water harvesting from roads in Tigray, Northern Ethiopia:Practices, Opportunities and Design Considerations.

Lasage, R., and Verburg, P. H., 2015, Evaluation of small scale water harvesting techniques for semi-arid environments: JOURNAL OF ARID ENVIRONMENTS, v. 118 p. 48-57.

Ngigi, S. N., 2003, Rainwater harvesting for improved food security: Promising technologies in the Greater Horn of Africa. Nairobi, Kenya: Greater Horn of Africa Rainwater Partnership (GHARP) and Kenya Rainwater Harvesting Association (KRA), with support from the United States Agency for International Development (USAID).

Seleshi, B., Philippe, L., and Taffa, T., 2009, Water harvesting and development for improving productivity, Addis Ababa, Ethiopia, Improving Productivity and Market Success (IPMS) of Ethiopian farmers project, International Livestock Research Institute (ILRI).

Seleshi, B. A., Philippe, L., and Taffa, T., 2006, Best Practices and Technologies for Small Scale Agricultural Water Management in Ethiopia.: Proceedings, Addis Ababa Ministry of Water Resource, USAID, IWMI.

Taffa, T., 2002, Soil and Water Conservation for Sustainable Agriculture. Mega Publishing Enterprise. CTA, Postbus 380, 6700 AJ Wageningen, The Netherlands.

Tireza, N., Eyasu, Y., and Nata, T., 2013, Quantification of the Impact of Integrated Soil and Water Conservation Measures on Groundwater Availability in Mendae Catchment, Abraha We-Atsebaha, eastern Tigray, Ethiopia: Momona Ethiopian Journal of Science (MEJS), v. 5(2), p. 117-136.

Tsegay, W., Kiros, M., Amanuel, Z., and Aklilu, H., 2010, Climate Change Adaptation and Impact Mitigation: A case study of Abreha Wa Atsbeha Village in Tigray, Northern Ethiopia.: Journal of Drylands v. 3(1), p. 150-157.

WAC, 2013, Recognizing local agro-ecological knowledge in sustainable intensification of tree-crop-livestock farming systems, World Agroforestry Centre: Nairobi, Kenya.

WKA, 2014, Annul Report of KelteAwelalo Wereda, in KelteAwelalo, S. A. o. W., ed.: Wukro, Tigray, Ethiopia.