**1.1 The Kinneret drainage basin**

The Kinneret drainage basin (total area 2730 km<sup>2</sup> ) is located mostly northern to the lake (**Figure 6**). Its maximum length from north to south is 110 km and widest 50 km. The Kinneret drainage basin is bounded between the Mount Hermon block and Litani basin in the north, Meron and Naftali mountain ridges in the west, the Golan Heights in the east, and Kinarot Valley in the south. The highest altitude point within the Kinneret basin (Hermon summit) is 2814 m (ASL). Taking into account Kinneret common water level (WL) as 213 m (BSL), the total slope of 3027 m along 110 km makes the mean surface gradient as 2.8%. The Hula Valley is flat with a mean slope of appox. 0.7%. The Kinneret basin comprises the following subunits: northern basin including Jordan drainage basin drained by the rivers: Hermon, Dan, and Snir, and the Hula Valley-1530 km<sup>2</sup> (56%); eastern basin drained by several rivers (Meshushim, Daliyot, Zavitan, and others)-580 km2 (21%); western basin drained by the rivers of Zalmon and Amud—450 km2 (16%); and several other small parts southern and western to the lake.

### **1.2 A brief historical survey of the Hula Valley management**

During the last 80 years, the Lake Kinneret drainage basin ecosystems have undergone significant anthropogenic and natural modifications. Prior to the 1950s, the Hula Valley was mostly (6500 ha) covered with old Lake Hula (1300 ha) and swampy wetlands. This area was not cultivated, malaria was common, and water loss by evapotranspiration (ET) was significant. The Jordan River crossing the Hula Valley contributes about 63% of the downstream of the Lake Kinneret's water budget, but 70% of the total nutrient inputs, of which over 50% originate in the Hula Valley region, including the valley and the slopes on both sides (east and west) of it. Old Lake Hula and swamps were drained and were being converted for agricultural development. Years later, land utilization was modified in an operation referred to as the Hula Reclamation Project (HRP) which was improved later. The HRP included creation of a new shallow lake Agmon (surface area of 1120 ha, mean depth—0.45 m., volume—0.44 × 106 m3 ), renewal of 90 km drainage and water supply canals, placing a vertical plastic barrier along 2.8 km crossing the valley from east to west, maintenance of higher underground water table, and functional conversion of 500 ha with lake Agmon in the center from agricultural to eco-tourism usage. The objectives of HPR were aimed at: (1) nutrient removal from the Lake Kinneret external loads through the Lake Agmon hydrological system; (2) to produce an ecological component for eco-tourism-Lake Agmon; and (3) the usage of Lake Agmon as a principal component for the hydrological management and agricultural irrigation system for the entire valley. The following objectives were implemented: improvement of irrigation water supply, maintenance of high underground water table ensuring peat soil moisture to prevent its deterioration, and the achievement of a high diversity of re-establishment of natural flora and fauna emphasizing aquatic birds.

Prior to the drainage of old Lake Hula and adjacent swamps during 1950–1957, Nitrogen was fluxed from the basin to the lake, mostly as highly bioavailable ammonia, but after the Hula drainage, the dominant N was modified to nitrate. Before the mid-1990s, a daily volume of 25 × 103 m3 of raw sewage and fishpond (1700 ha) effluents rich with ammonia fluxed into Lake Kinneret. The fishpond area was dramatically reduced (450 ha), as well as its effluents, and the raw sewage was stored in reservoirs and reused. As a result of inappropriate irrigation and agricultural methods, the peat soil quality deteriorated by consolidation, destruction, and surface subsidence. It was accompanied by heavy dust storms, blocking of drainage canals, enhancement of underground fires, and outbreaks of rodent populations. These deteriorated processes caused severe damage to agricultural crops. A reclamation project (HRP) was consequently implemented.

The aim of the present paper is to evaluate the outcome of the anthropogenic intervention in the Hula Valley, together with climate change, on the management of Lake Kinneret, its water quality, and the entire ecosystem structure trait.
