1.7 Groundwater 1.7 Groundwater The WFD requires that initial characterization Figure 1.7.1 of the location and boundaries of all groundwa- Map indicating loca- ter bodies be carried out in connection with the N tion and boundaries Article 5 report. In addition the initial charac- of aquifers in Odense terization must identify the pressures on the River Basin. groundwater bodies and the character of overly- ing strata, and must identify those groundwater bodies for which there are directly dependent surface water ecosystems or terrestrial ecosys- tems. If the initial characterization reveals that spe- cifi c groundwater bodies are at risk of failing to meet the environmental objectives set, these groundwater bodies have to be characterized further. Among other things, their geological and hydrogeological characteristics have to be described. In addition, the chemical composition of the groundwater has to be characterized, as has groundwater recharge and exchange of water between the groundwater body and associated surface systems. 0 5 10 km 1.7.1 Initial characterization This section describes the initial characteriza- tion of aquifers and groundwater abstraction in Table 1.7.1. From Table 1.7.2 it can be seen that Odense River Basin. Subsequently a single aqui- 20 aquifers are smaller than 15 km2, and that 12 fer has been selected for further characterization, of these are smaller than 5 km2. Table 1.7.1 would including subdivision into groundwater bodies. seem to indicate, moreover, that the majority of Odense River Basin is covered by aquifers. This Aquifers is not the case, however, in that the parts of the The location and boundaries of the aquifers aquifers that lie outside Odense River Basin are within Odense River Basin are illustrated in Fig- also included in the total aquifer area. Moreover, ure 1.7.1. The aquifers are included if just part of several aquifers may very well overlap in places, the aquifer lies within Odense River Basin, even separated by impervious clay layers. if only a limited part. As mentioned earlier, a number of the aquifers A summary of the aquifers is shown in Table are only partly located within Odense River Ba- 1.7.1 based on the data for the individual aquifers sin. For example, the major part of aquifers 3, 7N shown in Table 1.7.2 (Fyns Amt, 2000b). Due to and 39 are located outside the basin. These rela- the large range in aquifer size it makes a consider- tively large aquifers comprise approx. 50% of the able difference whether one considers the mean water resource. Abstraction from these aquifers or the median values, as is also apparent from is limited seen in relation to their size, however. Max Min Median Mean Total Table 1.7.1 Statistics for all aqui- Aquifer area (km2) 187 0.4 9.8 29.7 1 009 fers encompassed by Odense River Basin. Aquifer resource (106 m3) 1 472 0.6 30 146 4 956 Waterworks abstraction in 1998 (103 m3) 4 173 0 152 565 18 627 Total abstraction in 1998 (103 m3) 5 628 0 161 772 25 498 Odense PRB Odense Pilot River Basin 43 44 BK: Danien bryozo limestone; PK: Selandien greensand limestone; IS: Interglacial freshwaterDescription sand. of the individual aquifers encompassed by Odense River Basin. DS: Late-glacialTable meltwater sand; 1.7.2 DG: Late-glacial mel Aquifer name/identity Aquifer Layer in Cover layer Area Resource Aquifer Geology Waterworks Total abstrac- Groundwater 1.7 number geological class (km2) (106 m3) type abstraction in 1998 tion in 1998 model (106 m3) (106 m3) Tarup-Årslev 1Ø 3 A1 28.8 129.6 U DS 56 161 Tarup-Årslev 1V 3 A1 24.7 111.15 U DS 294 307 Langeskov 3 5 B1 74.5 223.5 C DS 273 644 Gislev 5 3 A1 4.7 28.2 C DS 188 188 Ringe-Ryslinge 6 3 B2 25.0 112.5 C DS 1 217 1 220 Nyborg 7N 9 B1 122.7 1 472.4 C BK, PK 1 246 1 576 Aquifer complex near Odense 8 5 B1 186.9 582.6 U, C DS 1 585 5 628 Holmehave 9 7 C2 11.4 68.4 C DS 97 108 Frøbjerg 12 3 A1 5.6 16.8 U DG 0 0 Vissenbjerg-Blommenslyst 16 5 A3 33.0 148.5 U, C DS 591 603 Odense PRB Korinth 17 1 A1 7.2 21.6 U, C DS 0 1 Aquifer at Lake Arreskov 18 3 A1 19.9 59.7 U, C DS 13 33 Aquifer north of Espe 20 3 A3 2.5 7.5 C DS, DG 274 281 Odense Pilot River Basin Limestone aquifer – Odense 23 9 C1 17,5 C PK, BK Deep aquifer at Holmehave 24 9 C2 18.0 C, A DS 4 173 4 173 Stenstrup-Lunde 27 3 A2 9.3 13.95 U, C DS 0 0 Kværndrup 35 3 B2 2.9 13.05 C DS, IS 256 256 Lake Søndersø 39 3 A1 182.6 821.7 U, C DS 855 1 072 Northern Odense aquifer 40 7 B2 139.2 626.4 C DS 1 800 3 378 Seden-Bullerup 41 7 A3 11.4 51.3 C DS 0 82 Hasmark 42 7 A2 10.2 45.9 C DS 72 109 Mesinge 44 7 B2 21.4 64.2 C DS, DG 152 157 Munkebo aquifer – upper part 45 3 A2 4.7 7.05 U, C DS, DG 30 30 Munkebo aquifer – lower part 46 7 B2 5.5 8.25 C DS 83 83 Morud 50 5 B3 3.2 9.6 C DS 253 253 Vester Hæsinge 60 7 C1 0.4 0.6 C DS 90 90 Aquifer at Tommerup 63 5 C2 21.1 63.3 C DS 515 516 Trunderup 65 5 B1 2.7 8.1 U, C DS 49 49 Broby 66 7 B1 10.3 30.9 U, C DS 130 160 Deep aquifer at Fruens Bøge 90 7 B1 3.9 163.8 C DG, DS 3 041 3 041 Aquifer north of Sanderum 91 7 C2 0.6 9.0 C DS, DG 0 0 Aquifer north of Brylle 93 7 B2 3.2 9.6 C, A DS, DG 1 260 1 260 twater gravel; Aquifer northwest of Lake Søndersø 102 7 C1 1.7 5.1 C DS 0 1 Kappendrup 105 9 C1 1.2 3.6 C DS, DG 34 38 1.7 Groundwater Class Description Cover layer class Description Table 1.7.3 Classifi cation of cover A The cover layer thickness exceeds A1 A considerable part of the cover layer layer classes. 15 m in less than 25% of the total is less than 5 m thick. area of the aquifer. A2 There are no significant areas where the cover layer is less than 5 m thick, and heavy clay is not present to any great extent above the aquifer. A3 Heavy clay occurs above the aquifer. B The cover layer thickness exceeds B1 Areas are present where the cover 15 m in more than 25% of the total layer is less than 5 m thick. area of the aquifer. In addition, the B2 The cover layer is never less than 5 cover layer is less than 15 m thick in m thick, and only insignificant areas more than 5% of the total area of the of heavy clay occur above the aquifer. aquifer. B3 Significant deposits of heavy clay above the aquifer. C The cover layer thickness exceeds C1 There are no significant deposits of 15 m in more than 25% of the total heavy clay above the aquifer. area of the aquifer. In addition, the C2 Significant deposits of heavy clay cover layer is less than 15 m thick in above the aquifer. less than 5% of the total area of the aquifer. A geological layer model has been established tion to the aquifers and the degree of exploitation in which layer 1 represents the unsaturated zone, vary considerably. layers 3, 5, 7 and 9 are the water-bearing layers (aquifers), with layer 3 uppermost and layer 9 Groundwater potential lowermost. Layers 2, 4, 6 and 8 are the inter- A potential map for the primary water table has mediate impervious layers, of which layer 2 is been prepared from sounding data (Figure 1.7.2). uppermost. The cover layer classes refer to the As this is primarily based on soundings from the distribution of the cover layer overlying the aqui- primary water table, it is possible that a second- fer (Table 1.7.3). The aquifer types are as follows: ary water table closer to the surface might exist U: Unconfi ned; C: Confi ned; and A: Artesian. locally. As areas without aquifers have also been Certain aquifers contain several types, including assigned a water table, the potential lines cannot both unconfi ned and confi ned. be utilized to accurately determine the magni- With a number of the aquifers it is apparent tude or direction of groundwater fl ow. that abstraction amounts to less than the mini- mum requirement of 10 m3/day for drinking Aquifer protection water, e.g. aquifers 12, 27, 91 and 102. They are Clay thickness above the aquifer nevertheless included because it is as yet unclear The thickness of the clay overlying the indi- whether groundwater fl ow in these aquifers vidual aquifers is indicated in Figure 1.7.3. The affects terrestrial ecosystems or surface water clay thickness map is not complete for the whole ecosystems.