Fig. 1
Location of measuring stations.
1 – the river bed before the excavation; 2 – contemporary river bed; 3 – IMWM water gauge station (IMWM - Institute of Meteorology and Water Management); 4 – well; 5 – measuring cross-section; 6 – hypsometric section line (ortophotomap: Google Earth Pro).
Table 1
Hydrological variation in the Moszczenica catchment (based on Jokiel 2004).
| Section of Moszczenica | Total runoff | Groundwater runoff | Share of groundwater runoff in the total runoff | Specific total runoff | Specific groundwater runoff | Share of specific groundwater runoff in the specific total runoff |
|---|---|---|---|---|---|---|
| [dm3 · s−1 · km−2] | [%] | [dm3 · s−1 · km−2] | [%] | |||
| Upper | 4–5 | 3–4 | 60–70 | 6.1–7.0 | 3.6–4.0 | >60 |
| Middle | 4–5 | 2–3 | 50–60 | 5.1–6.0 | 3.1–3.5 | 56–60 |
| Lower | 3–4 | <2 | 40–50 | 4.1–5.0 | 2.6–3.0 | 51–55 |
Fig. 2
Water level measured in the gauging station of the IMWM in Gieczno during the 2017–2018 hydrological year. Red dots – days of taking measurements. IMWM – Institute of Meteorology and Water Management.
Fig. 3
Changes in the state groundwater and state of Moszczenica levels at the water gauge in Gieczno.
Table 2
Water levels in the riverbed, water table in observation wells and hydraulic gradients in the Moszczenica bottom in upwelling zones.
| Date | Hr | No. 6 | No. 3 | ΔL [m] | 875 | ΔR [m] | 432 |
|---|---|---|---|---|---|---|---|
| Δ (No. 6 – Hr) | Grad L | Δ (No. 3 – Hr) | Grad R | ||||
| [m a.s.l.] | [m] | [−] | [m] | [−] | |||
| Oct-15 | 114.94 | 116.78 | 115.95 | 1.84 | 0.0021 | 1.01 | 0.0023 |
| Nov-15 | 114.96 | 116.88 | 115.87 | 1.92 | 0.0022 | 0.91 | 0.0021 |
| Dec-15 | 114.99 | 117.16 | 116.10 | 2.18 | 0.0025 | 1.12 | 0.0026 |
| Jan-16 | 115.09 | 117.20 | 116.07 | 2.11 | 0.0024 | 0.98 | 0.0023 |
| Feb-16 | 115.01 | 117.26 | 116.13 | 2.25 | 0.0026 | 1.12 | 0.0026 |
| Apr-16 | 115.08 | 117.70 | 116.43 | 2.62 | 0.0030 | 1.35 | 0.0031 |
| May-16 | 114.94 | 117.30 | 116.33 | 2.36 | 0.0027 | 1.39 | 0.0032 |
| Jun-16 | 114.91 | 117.50 | 116.27 | 2.59 | 0.0030 | 1.36 | 0.0031 |
| Jul-16 | 114.92 | 117.10 | 116.17 | 2.18 | 0.0025 | 1.25 | 0.0029 |
| Aug-16 | 114.89 | 117.20 | 116.10 | 2.31 | 0.0026 | 1.21 | 0.0028 |
| Sep-16 | 114.87 | 117.15 | 115.77 | 2.28 | 0.0026 | 0.90 | 0.0021 |
| Oct-16 | 114.98 | 117.20 | 116.12 | 2.22 | 0.0025 | 1.15 | 0.0027 |
| Nov-16 | 115.15 | 117.28 | 116.40 | 2.13 | 0.0024 | 1.25 | 0.0029 |
| Feb-17 | 115.30 | 117.50 | 116.61 | 2.21 | 0.0025 | 1.32 | 0.0030 |
| Apr-17 | 115.00 | 117.26 | 116.72 | 2.26 | 0.0026 | 1.72 | 0.0040 |
| May-17 | 114.94 | 117.10 | 116.94 | 2.16 | 0.0025 | 2.00 | 0.0046 |
| Jun-17 | 114.88 | 117.00 | 116.79 | 2.13 | 0.0024 | 1.92 | 0.0044 |
| Jul-17 | 114.91 | 117.08 | 116.70 | 2.17 | 0.0025 | 1.79 | 0.0041 |
| Sep-17 | 115.13 | 117.20 | 116.94 | 2.07 | 0.0024 | 1.81 | 0.0042 |
| Oct-17 | 115.12 | 117.15 | 117.00 | 2.03 | 0.0023 | 1.88 | 0.0044 |
| Dec-17 | 115.17 | 117.35 | 116.65 | 2.18 | 0.0025 | 1.48 | 0.0034 |
| Jan-18 | 115.20 | 117.60 | 116.72 | 2.40 | 0.0027 | 1.52 | 0.0035 |
| Feb-18 | 115.08 | 117.60 | 116.52 | 2.52 | 0.0029 | 1.44 | 0.0033 |
| Apr-18 | 114.98 | 117.53 | 116.58 | 2.55 | 0.0029 | 1.60 | 0.0037 |
| Jun-18 | 114.89 | 117.48 | 116.60 | 2.59 | 0.0030 | 1.71 | 0.0040 |
| Jul-18 | 114.93 | 117.40 | 116.57 | 2.47 | 0.0028 | 1.64 | 0.0038 |
| Oct-18 | 115.00 | 117.63 | 116.66 | 2.63 | 0.0030 | 1.66 | 0.0038 |
| Nov-18 | 114.97 | 117.71 | 116.64 | 2.74 | 0.0031 | 1.67 | 0.0039 |
| Dec-18 | 115.02 | 117.75 | 116.70 | 2.73 | 0.0031 | 1.68 | 0.0039 |
| 0.0026 | gradav | 0.0033 | |||||
Fig. 4
Construction of a gradientmeter. 1 – screen, 2 – piezometer embedded into bottom sediments, 3 – pressure ring, 4 – bracket, 5 – hose to piezometer, 6 – piezometer measuring tube, 7 – measuring tube for surface waters, 8 – valve, 9 – hose submerged in surface waters.
Fig. 5
Grain size analysis of bottom sediments of the Moszczenica River.
Table 3
Granulometric and hydraulic characteristics of the Moszczenica riverbed sediments.
| Parameters | P1 | P4 | P9 | |||
|---|---|---|---|---|---|---|
| Fractions | ||||||
| Gravel % (10–2 mm) | 5.70 | 1.26 | 24.45 | 2.64 | 49.37 | 0.46 |
| Sand % (2–0.1 mm) | 85.78 | 65.48 | 77.43 | 76.29 | 44.06 | 34.30 |
| Silt % (0.1–0.01 mm) | 8.43 | 29.95 | 6.14 | 20.72 | 6.36 | 62.76 |
| Loam % (< 0.01 mm) | 0.09 | 3.30 | 2.13 | 0.35 | 0.22 | 2.48 |
| Equivalent grain diameters and grain distribution unevenness index | ||||||
| d10 [mm] | 0.055 | 0.013 | 0.088 | 0.023 | 0.079 | 0.013 |
| d20 [mm] | 0.086 | 0.024 | 0.130 | 0.048 | 0.140 | 0.016 |
| d60 [mm] | 0.210 | 0.120 | 0.370 | 0.140 | 2.300 | 0.044 |
| Hydraulic conductivity | ||||||
| U | 3.82 | 9.23 | 4.21 | 6.09 | 29.11 | 3.39 |
| k10 [m · s−1] | 1.28 · 10−3 | 6.77 · 10−5 | 3.30 · 10−3 | 3.34 · 10−4 | 3.91 · 10−3 | 2.67 · 10−5 |
Fig. 6
Place of measurements of the hydraulic gradient on the straight section of the Moszczenica River (the arrow shows the direction of the river flow).
Fig. 7
Hypsometric profile of the area in the bottom part of the Moszczenica valley between Wypychów and Gieczno (Fig. 1C). Based on the digital elevation model of the Geoportal of the Łódzkie Voivodship.
Table 4
Characteristic water level and flow of the Moszczenica River measured in the gauging station in Gieczno in 1971–1990 (after Szczepański 1995).
| Water level [cm] | |
| Extremely high stage | 316 |
| Extremely low stage | 120 |
| Flow [m3 · s−1] | |
| Extremely high flow | 9.42 |
| Medium high flow | 4.72 |
| Medium mean flow | 0.92 |
| Medium low flow | 0.29 |
| Extremely low flow | 0.17 |
Fig. 8
Changeability of the hydraulic gradient in the Moszczenica River hyporheic zone during different flow conditions.
Fig. 9
Hydraulic gradient changeability in the river bottom during low water stage. A – Spatial distribution of water depth, B – Spatial distribution of hydraulic gradient.
Fig. 10
Hydraulic gradient changeability in the river bottom during high water stage. A – Spatial distribution of water depth, B – Spatial distribution of hydraulic gradient.
Fig. 11
A – Variability of hydraulic gradient in cross-sections along the Moszczenica river bed in the section with a predominance of downwelling, B – Variability of hydraulic gradient in cross-sections along the Moszczenica river bed in the transition zone between the dominant downwelling and upwelling, C – Variability of hydraulic gradient in cross-sections along the Moszczenica river bed in the section with a predominance of upwelling.
Table 5
Analysis of the hydraulic gradient results in the Moszczenica bottom at different water levels.
| Parameter | Low water level | High water level | ||
|---|---|---|---|---|
| A B C D E | A C E | |||
| Upwelling | Downwelling | Upwelling | Downwelling | |
| Maximum | 0.075 | −0.000 | 0.030 | −0.000 |
| Minimum | 0.000 | −0.015 | 0.000 | −0.110 |
| Average | 0.016 | −0.008 | 0.018 | −0.027 |
| Median | 0.010 | −0.005 | 0.025 | −0.025 |
| Number | 27 | 6 | 3 | 18 |
| Share | 81.8% | 18.2% | 14.3% | 85.7% |
Table 6
Statistical analysis of the results of the hydraulic gradient research in the bottom of the Moszczenica for the canal, transitional zone and the natural riverbed.
| Parameter | Artificial canal | Transition zone | Natural riverbed | Together | ||||
|---|---|---|---|---|---|---|---|---|
| P1–P5 | P6–P8 | P9–P13 | P1–P13 | |||||
| Upwelling | Downwelling | Upwelling | Downwelling | Upwelling | Downwelling | Upwelling | Downwelling | |
| Maximum | 0.005 | −0.000 | 0.045 | −0.000 | 0.055 | −0.000 | 0.055 | −0.000 |
| Minimum | 0.000 | −0.085 | 0.000 | −0.040 | 0.000 | −0.065 | 0.000 | −0.085 |
| Average | 0.003 | −0.029 | 0.018 | −0.025 | 0.023 | −0.023 | 0.019 | −0.027 |
| Median | 0.005 | −0.020 | 0.020 | −0.030 | 0.023 | −0.015 | 0.018 | −0.020 |
| Number | 3 | 15 | 7 | 4 | 12 | 5 | 22 | 24 |
| Share [%] | 16.7 | 83.3 | 63.6 | 36.4 | 70.6 | 29.4 | 47.8 | 52.2 |
Table 7
Results of the water flow rate measurement in the canal of the Moszczenica.
| Canal | Distance | Flow | Comments |
|---|---|---|---|
| [m] | [m3 · s−1] | ||
| P1 | 0 | 1.1747 | |
| P2 | 92 | 1.0654 | In front of the ditch |
| P3 | 88 | 1.1795 | Behind the pond |
| P4 | 80 | 1.2264 |
Fig. 12
Changes in the water flow rate in the Moszczenica River along the downwelling section.