Guidelines for Rehabilitation of Rivers
Friedler and Juanico (1996) proposed guidelines for water allocation for rehabilitation of rivers in Israel. This appendix therefore focuses on Israel's rivers but the biophysical principles apply to all rivers in the study area, including the Jordan River. The river should have waters that sustain biodiversity, provide the ecosystem service of ''open space," and also allow for economic development along the river course. With respect to water quantity, at less than 10 percent of natural base flow (excluding stormwater) the river ceases to function as a river, whereas this 10 percent flow quantity can be tolerated, provided this low flow only occurs for short periods. To maintain the aquatic and riparian biodiversity, however, 30 percent of natural base flow is minimal sustained average. Flood flows are critical too. Floods remove deposits accumulated during the long summer that would otherwise obstruct the flow. Water quality standards are proposed for chlorination (carried out to meet health requirements, but which can be toxic to all fish), for organic load (high load causes dangerous anoxia), for ammonium (which can generate toxic ammonia) and for pH and salinity (which must be kept within ranges prevalent in the natural stream). A prerequisite for meeting these standards is that the velocity should not be lower than 0.2 m/sec (with water width and depth of at least 5 m and 0.5 m, respectively). It should be noted that compliance with human health regulations alone can still be destructive to the river's aquatic biodiversity. The recipe and timetable for the rehabilitation of the "dead" rivers of Israel is as follows: (1) a legal procedure of water allocation to the river should be completed, and the discharge of
the allocated water should proceed; (2) point pollution sources along the river course should be removed, and at the same time nonpoint pollution sources should be identified and controlled; (3) measures for secondary treatment of sewage sources should be taken; and (4) tertiary treatment should be applied, and facilities for pooling wastewater to control the flow of the river should be constructed and operated.
Rehabilitation of the Yarkon, Alexander, and Soreq Rivers
The 28 km of the Yarkon River meander through Israel's most densely populated area. The discharge of the source of Yarkon river, Ein Afek springs, was 220 to 200 million m3/yr of water prior to the transportation of most of it to irrigate the Negev in 1955. The river died out, and to rehabilitate it, 65 million m3/yr of water were allocated in 1992. The effect on the river was most dramatically expressed in the return of its fish fauna. But later this amount was reduced, from the pressures of other users, and the state of the river deteriorated. The master plan for rehabilitating the river (Rahamimov, 1996), commissioned by the Yarkon River Authority, which was established in 1988, paves the way for full rehabilitation of the river. The master plan follows the guidelines for river rehabilitation in Israel and is based on the premise that only 9 million m3/yr of freshwater could be allocated, with the rest replaced by treated wastewater, 12 million m3/yr of which is already allocated. The allocation to be released from the impounded Ein Afek springs, together with the allocation of treated wastewater, is to guarantee 10 percent of the original flow—2,500 m3/hr. The water will be sold to users along the river course, that is to authorities who will operate parts of the riparian areas as recreational areas. Finally, prior to reaching the last, saline section of the river, the water will be impounded for conventional use. Thus, except for the little water lost by evaporation, there will be no losses to the national water budget. Percolated water will recharge the aquifer, and the rest will be sold twice. This arrangement should fully compensate for the cost of impounding the water downstream rather than upstream near the source (i.e., will cover the cost of uplifting the water for users above the point of impoundment). Hundreds of tons of garbage have been removed from the river to restore its original depth, the river's banks have been cleaned up, reinforced, and raised, sewage treatment plants in some cities discharging wastewater to the river have been inaugurated, and mosquito larvae are controlled by introduced predatory fish (Gambusia) and by seasonal application of Baillus thuringiensis israelensis (BTI), a mosquito larvae—specific pathogen, inert to all other forms of life. The last approach is a demonstration of the potential use of local biodiversity—this
pathogen, discovered in an Israeli ephemeral pond, has become the major means of control of local mosquitoes, and also a source of income as an export product.
Following the example of the Yarkon River, the 44 km of the Alexander river, inhabited by a relatively large and sole population of the Nile softshell turtle (Trionyx triunguis), is being rehabilitated as of 1995, and now receives 225,000 m3/hr from various sources. The Soreq river used to be a permanent coastal river, with winter floods added by stream from the Soreq mountains. This stream currently is a permanent flow of Jerusalem's 14 million m3/yr of sewage, 20 percent of which is lost by percolation prior to reaching the coastal plain. The remainder reaches treatment plants in the foothills and is used for irrigating cotton. A proposal has been made to create a continuous flow along the coastal part, with 15 million m3/yr of treated wastewater from local towns.
Securing Allocations of Water for Aquatic and Riparian Ecosystems
The Legal Status of Water in Israel and the Quota of Water for Nature
All the waters of Israel belongs to the State, but legislation concerning pricing distinguishes between pumped water and natural water, such as direct rainfall, surface runoff, natural, open streams, pools, and other water bodies. All protected areas in Israel, both nature reserves and national parks, are the property of government authorities, the Nature Reserves Authority and National Parks Authority (recently united into one authority reporting to the Ministry of the Environment). Water sources within protected areas, as elsewhere, are managed by the Water Commissioner. However, natural water that is charged to users elsewhere is not charged to the Nature Reserves Authority, who is the user. Nevertheless, in each specific case permits are negotiated between the Nature Reserves Authority and the Water Commissioner, but other traditional and potential users who contest the proposed water use are involved in the negotiations. Legally, all agreed-upon permits are temporary and can be revoked at any time by the Water Commissioner, with no provision for alternative sources of water.
Criteria for Allocations of Water for Nature
Research has not been carried out in the study area to determine the quantity and quality of water required by natural ecosystems for maintaining their biodiversity and providing their services. Guidelines are
also lacking for drylands outside the region. The rule of thumb of the Israeli Nature Reserves Authority is to negotiate for the natural quantity and quality first, and finally to settle on the best compromise possible. Once an allocation is determined, the Nature Reserves Authority guards it tenaciously against all future attempts to challenge this allocation. Such attempts become frequent, as water demands in the study area increase. It is likely that the agreed allocations will become unacceptable to alternative users, and the authorities will then face pressures to reduce the allocations for nature. Just as for agriculture, natural ecosystems will have to compete with agriculture for treated wastewater. Precise objectives will be needed for each aquatic, riparian, and other water-dependent site in the study area (referring, e.g., to the type of biodiversity to be maintained and the types of ecosystem services required), and studies will be needed to determine the minimal required allocation of quantity and quality. Indicators, benchmarks, and monitoring programs for each of the sites will have to be identified and carried out for reviewing and updating water allocations.
The Case of Allocation for the Ein-Geddi Reserve
Several year-round discharging springs nurture the Ein-Geddi oasis near the Israeli coast of the Dead Sea. The biodiversity of this oasis is an Ethiopian relict island in an "ocean" of Saharo-Arabian biota. Significant species for ecosystemic function as well as tangible inspirational value, are the ibex and its predator, the leopard. The oasis is a nature reserve, but Kibbutz Ein-Geddi, located next to the oasis, is provided with water by the Ein-Geddi springs for its agricultural and domestic needs. Legally, the Kibbutz is entitled to use all the discharge of the spring, which are fully impounded. However, the Kibbutz uses the spring for potable domestic use only. The remainder flows in a stream that feeds the reserve, but is then transported for other domestic uses of the Kibbutz and for its agriculture. Only what remains then, which fluctuates much between years, is to be left solely for the reserve. So far the overall Kibbutz needs have been less than the discharge, and therefore there have always been some water in the reserve. Yet agreements have been negotiated, to guarantee 20 m3/hr for the reserve. In practice, of the 339 m3/hr average discharge of all Ein Geddi springs, 264 m3/hr is for all users, and 75 m3/hr are left for biodiversity.
It has now been realized that to prevent total extinction of the reserve's water-dependent vegetation, 84 m3/hr are required. The average annual gap of 9 m3/hr has to be filled by increasing the allocation to the reserve at the expense of the upstream users, or by developing new water resources for nature, such as wells dug into the alluvial fans next to the
Dead Sea shores, which store flood and drainage water (Hendelsman, 1990).
Current Allocations in Israel
Negotiations on water quota in Israel have so far yielded an array of interesting arrangements for allocating water to nature (i.e., for promoting biodiversity and ecosystem services) and sharing water sources with other users. The following is a review of these arrangements, identifying the amounts of water involved.
Springs and Small Streams. Water allocation arrangements for springs and small streams include the following:
- One stream with a rare aquatic plant and another stream with an endemic Israeli fish are allocated the whole discharge of their respective springs; in two nature reserves, the flow is impounded after leaving the protected areas.
- Five nature reserves are allocated a fixed quantity of the discharge, ranging from 10,000 m3/yr in one reserve to 1,051,200 m3/yr in another.
- Three nature reserves receive variable allocations, depending on the variations in the discharge: one reserve is allocated a minimum of 60 m3/hr, but when the discharge is 120-200 m3/hr, half of the discharge is released for nature, and when it is above 200 m3/hr, 100 m3/hr is allocated to nature; in another reserve, 1 m3/sec is allocated in an average year, but in dry years allocation is curtailed proportionally to the curtailment of allocation to other users, provided that at least 0.5 m3/sec is allocated for nature; and in the third reserve, the allocation is not less than 52,560 m3/yr, with extra amounts depending on other users.
- For three reserves, there are priority rights and allocations set for other users, and nature receives the remainder, if any;
- In two reserves, all water can be taken for other uses, provided water flow persists even in dry summer, at a continuous flow in the channel.
- A mixed arrangement has been made for Har Meron Nature Reserve, the largest nonaquatic protected area in the Mediterranean highlands: all springs within the reserve except one are allocated for nature; for the other, nature and other users share the discharge equally.
- An interesting case is that of Gush Halav Spring near the Har Meron reserve. This spring traditionally served the needs of the village of Gush Halav for generations. With recent increasing water demands the village was connected to the national grid and the domestic and agricultural use of the spring ceased, its water becoming the property of nature
- by default. Recently, an entrepreneur requested use of the spring water for a mineral water industry. The negotiations involved the Nature Reserves Authority who claimed that all the 7 m3/hr and 10 m3/hr in summer and winter respectively are required for nature, and therefore objected to a permit for any industrial use.
Rivers. In mountain river reserves, sources are impounded, but some water is later released in several points along the course of the river. In Snir stream there are two points for releasing 11,388 m3 and 14,016 m3 respectively in an average year and 6,132 m3 and 7,446 m3 respectively in a dry year. In Kziv stream there are three points of release of fixed quantities irrespective of the type of year, totaling 328,000 m3/yr. The Taninim River is the only coastal river that has a nature reserve status. All other coastal rivers of Israel have died; some are at various stages of rehabilitation. Currently the river is allocated a minimum of 3,504,000 m3/yr. This is provided by a flow of 110 1/sec. When the flow is above 530 1/sec, on each 30 1/sec increment, there is a 101/sec increment in the allocation. When the flow is smaller than 420 1/sec, on each 30 1/sec depletion, the allocation is reduced by a 10 1/sec.
Wetlands. The Hula nature reserve is fed by a spring, and by a canal that replaces in part the predrainage discharge of the Jordan River. The spring water is divided between agriculture and the reserve, such that when the discharge is below 300 m3/hr all this amount is allocated to the reserve; when the discharge is lower than 450 m3/hr, 600 m3/hr, and 750 m3/hr, the allocation to agriculture is 100 m3/hr, 125 m3/hr, and 150 m3/hr, respectively; and when it is more than 750 m3/hr, agriculture receives 200 m3/hr.
In effect, in winter the allocation is 1,000 m3/hr for agriculture and 500 m3/hr, as well as the excess of agriculture for the reserve. Altogether the average allocation is 1,532,000 m3/yr for the reserve. The Western Canal discharges 4 million m3/yr to the reserve, but most of this is marginal water—wastewater and aquaculture effluents. In a much smaller wetland in the Hula region, the Gonen meadow, the water allocation is small—it maintains moisture in the reserve.
Allocation of "Nonnatural" Water for Nature
There are two cases of specific allocation of "nonnatural" water to nature: in one case an overflow of storage next to a reserve is allocated to the reserve. In another case the reserve is allocated 10,000 m3/yr from a well. Nonnatural water must be paid for by the Nature Reserves Authority, and so these allocations seem to have been not used ever.
The overall amount used in Israel for natural springs and small streams in nature reserves, which is contested by other users, currently is a minimum allocation of 18,200,760 m3/yr. This amount can be increased to at least 32,412,000 m3/yr. The maximum allocation is hard to calculate, since it requires data on the between-year variability in discharges of the various sources, as well as the variability in the allocations to other users. Large streams, rivers, and wetlands that are nature reserves are allocated at least 5,378,578 m3/yr. The maximum allocation, again, can not be calculated easily.
Thus, altogether the nature reserves of Israel are allocated between 23,579,338 m3/yr and 56,016,742 m3/yr, and more water is allocated depending on between-year variabilities in discharges and other uses. It seems, though, that legislation does not always guarantee the allocation, either because discharges are lower than expected, or because other users manage to obtain more than their share. For example, the allocations for three reserves—Hula, Ein Afek, and Kziv stream—combined for each reserve for the years 1991, 1992, and 1993 in thousands m3/yr were 5,724, 5,624 and 5,624, respectively, but the actual use by the reserves was only 3,682, 3,162, and 4,037, respectively. Nature reserves and rivers are also allocated water of lower quality (wastewater, untreated and treated), but reliable data on quantities are not yet available. Altogether, the 24 to 56 million m3/yr legally allocated for biodiversity and ecosystem services in Israel accounts for 0.9 percent to 2.0 percent of the total renewable water resources west of the Jordan Rift Valley (see Table 2.2). It should be borne in mind that, though much of this water evaporates, a substantial part recharges the aquifers and thus becomes available for further, possibly alternative, uses.
Environmental Impact Assessments
Israeli legislation requires environmental impact assessments for major development projects. Whether or not a project is major is decided by the Ministry of the Environment. However, many developers perform environmental surveys at their own initiative, so that they do not invest in projects that are likely to be rejected later on environmental grounds. The major water projects carried out in Israel have not been explored for their environmental effects prior to their execution. But this is gradually changing. Projects for pumped energy, such as creating artificial reservoirs above the Lake Kinneret/Lake Tiberias/Sea of Galilee or managing part of the Jordan River channel, have undergone a thorough environmental assessment process. Plans for impounding floodwater in the Negev are currently undergoing environmental assessment.
Most of these environmental impact assessments, however, concentrate
on effects on human health, aesthetics, risks of air and water pollution, and the risk for endangered species. The recognition of the significance of ecosystem services and the role of biodiversity in providing these services, beyond the endangered "flagship" species, is not yet expressed in environmental impact assessments.
The major future undertaking is to assess the impacts of wastewater use, for agriculture and for biodiversity, on biodiversity and ecosystem services. With respect to using treated wastewater to sustain biodiversity, predictions for water demand and use suggest that the current allocations for nature, as well as the recommendations of environmental impact assessments may not be respected in the future. Therefore, just as treated wastewater may in the future replace freshwater for agriculture, wastewater allocation for maintaining aquatic ecosystems and water-dependent terrestrial ecosystems may replace the current allocation of freshwater. Research is therefore required now for determining the effects and the technologies appropriate for this future substitution.
Urban development in one of the prime agricultural areas of Israel, the coastal plain, is currently motivating the transfer of agriculture to the northern Negev, namely, to the semiarid belt of Israel, which is also the climatic transition zone between desert and nondesert in Israel. The water required to sustain this agricultural development will be the effluents of the urban areas in the coastal plain. The treated wastewater is already transported from there to the northern Negev, and volume of water transportation will increase and proliferate. This new agricultural development will replace natural ecosystems whose biodiversity is of prime significance (Safriel et al., 1994), and which have not undergone any process of environmental assessment. It is certainly necessary to assess the impact of this development, but it is also essential to explore methods of regional planning that will minimize the damage especially to habitats that harbor indispensable biogenetic resources.
Friedler, E., and M. Juanico. 1996. Allocation of water for rehabilitation of selected rivers in Israel. Report to KKL.
Hendelsman, E. 1990. Water as a source of life. Nature Reserves Authority (in Hebrew).
Rahamimov, A. 1996. Master Plan for the Yarkon River. Tel-Aviv, Israel: Yarkon River Authority (in Hebrew).
Safriel, U. N., S. Volis, and S. Kark. 1994. Core and peripheral populations and global climate change. Israel J. of Plant Sciences 42:331-345.