. State Water Resources Control Board Temporary Urgency Change Order (2/4/2021) Russian River Hydrologic Report February 11, 2021 - February 18, 2021

Prepared as a requirement of the Order approving Sonoma Water's Petition for Temporary Urgency Change in Permits 12947A (Applications 12919A).

Instream Flow Requirements as of February 18, 2021 Basis Reach Instantaneous (cfs) Modified Per Order: Critical Condition Upper Russian River 25 D-1610: Dry Condition Dry Creek 75 D-1610: Dry Condition Lower Russian River 85

Upper Russian River based on criteria as established in the Order issued 2/4/2021 and amended 2/11/2021.

Lake Mendocino

Lake Mendocino Storage 2015 - 2021 and Storage Curve

120,000

100,000

80,000

60,000 Acre-feet

40,000

February 18, 2021 31,190 Acre-feet 20,000

2015 2016 2017 2018 2019 2020 2021 Storage Curve Minor Deviation Curve Dry Storage Threshold Critical Storage Threshold

0 0/1 1/1 2/1 1/1 2/1 3/1 4/1 5/1 6/1 7/1 8/1 9/1 1 1 1

Storage February 18, 2021 31,190 (acre-feet)

Total Average Daily Rate Change in Storage Last 30 days 1,001 33 (acre-feet) Last 7 days 1,391 199

Min 92 Daily Inflow Last 7 days Max 194 (cfs) Mean 134

Min 29 Release (cfs) Last 7 days Max 75 Mean 35

Release Flow Change Ramping Rates : Approved Adjusted Rates Event

Requested: 2/8/2021 Purpose: California Department of Fish and Wildlife (CDFW) requested Sonoma Water for an increase in discharge from Coyote Valley Dam to facilitate the release of steelhead smolts from the Coyote Valley Fish Facility. The increase in discharge is necessary to volitionally push the smolts out into the river to reduce the risk of predation.

Consultation: Ramping rate schedule below was agreed upon in Feb 3rd meeting of Sonoma Water staff with CDFW and National Marine Fisheries Service staff.

Flow Chang e New Set Point Date Time (cfs) (cfs) 8-Feb 12:00 PM +75 100 10-Feb 12:00 PM -25 75 10-Feb 8:00 PM -25 50 11-Feb 4:00 AM -25 25

Page 1

Lake Sonoma Storage 2015-2021 350,000

300,000

250,000

200,000 feet - Acre 150,000

February 18, 2021 157,046 Acre-feet

100,000

50,000

2015 2016 2017 2018 2019 2020 2021

0 1/1 2/1 3/1 4/1 5/1 6/1 7/1 8/1 9/1 10/1 11/1 12/1

Storage February 18, 2021 157,046 (acre-feet)

Total Average Daily Rate Change in Storage Last 30 days -12,020 -401 (acre-feet) Last 7 days -391 -56

Min 58 Daily Inflow Last 7 days Max 191 (acre-feet) Mean 110

Min 75 Release (cfs) Last 7 days Max 76 Mean 75

Page 2

PVP Diversion February 18, 2021 47 (cfs)

Lake Pillsbury

Parameter Date Range Cumulative Daily Average

October 1, 2020 - February 18, 2021 43,998 314 Inflow* (acre-feet) Last 7 days 7,521 1,074 *Inflow calculation based on criteria established in D1610

Lake Pillsbury Storage 2015-2021 and Target Storage Scenarios

90,000

80,000

70,000

60,000

50,000 Acre-feet 40,000

30,000 February 18, 2021 33,765 Acre-feet (Target C 43,547)

20,000

10,000

2015 2016 2017 2018 2019 2020 2021 Target A Target B Target C

0 1/1 1/8 2/5 3/4 4/1 4/8 5/6 6/3 7/1 7/8 8/5 9/2 9/9 1/15 1/22 1/29 2/12 2/19 2/26 3/11 3/18 3/25 4/15 4/22 4/29 5/13 5/20 5/27 6/10 6/17 6/24 7/15 7/22 7/29 8/12 8/19 8/26 9/16 9/23 9/30 10/7 11/4 12/2 12/9 10/14 10/21 10/28 11/11 11/18 11/25 12/16 12/23 12/30

Russian River Flows (February 11 - February 18, 2021)

24-hr Average Flow (cfs) Gage Feb 12, 2021 Feb 13, 2021 Feb 14, 2021 Feb 15, 2021 Feb 16, 2021 Feb 17, 2021 Feb 18, 2021

The Forks* 241 224 179 302 225 157 122

Talmage 303 280 247 393 335 229 177 USGS 11462080 Hopland 241 229 234 307 312 229 212 USGS 11462500 Cloverdale 287 298 361 359 482 372 302 USGS 11463000 Healdsburg 293 333 334 354 393 419 364 USGS 11464000 Hacienda 556 534 539 557 567 618 565 USGS 11467000 *West Fork (USGS 11461000) + East Fork (Coyote Valley Dam Release) Russian River Flows 700

600 Hacienda 500 Healdsburg

400 Cloverdale Hopland 300 Flow (cfs) Flow Talmage 200 The Forks

100

0 2/12/2021 2/13/2021 2/14/2021 2/15/2021 2/16/2021 2/17/2021 2/18/2021

Page 3 Russian River Water Quality (February 11 - February 18, 2021)

River Diversion Calpella Hopland Cloverdale* Jimtown* Diggers Bend Hacienda Bridge Johnsons Beach* Parameter System at Mirabel*

USGS 11461500 USGS 11462500 USGS 11463200 USGS 11463682 USGS 11463980 SCWA USGS 11467000 SCWA Min 46.8 48.2 #N/A 50.0 50.7 #N/A 51.3 #N/A Temperature 50.4 52.5 #N/A 56.1 55.6 #N/A 55.4 #N/A (°F) Max Mean 48.5 50.0 #N/A 53.2 53.3 #N/A 53.3 #N/A Specific Min 201 160 #N/A 0 236 #N/A 250 #N/A Conductivity Max 253 267 #N/A 0 305 #N/A 300 #N/A (µS/cm) Mean 231 205 #N/A #N/A 279 #N/A 272 #N/A Dissolved Min 10.8 9.3 #N/A 0.0 9.7 #N/A 9.6 #N/A Oxygen Max 11.9 11.6 #N/A 0.0 11.8 #N/A 11.8 #N/A (mg/L) Mean 11.2 10.5 #N/A #N/A 10.4 #N/A 10.4 #N/A Dissolved Min 91 80 #N/A 0 86 #N/A 85 #N/A Oxygen Max 105 105 #N/A 0 112 #N/A 112 #N/A (% Saturation) Mean 97 93 #N/A #N/A 94 #N/A 94 #N/A Min 7.9 7.4 #N/A 0.0 7.8 #N/A 7.8 #N/A pH Max 8.2 7.9 #N/A 0.0 8.2 #N/A 8.2 #N/A Mean 8.0 7.8 #N/A #N/A 7.9 #N/A 8.0 #N/A Min 9.7 3.5 #N/A 0.0 1.3 #N/A 2.3 #N/A Turbidity Max 59.6 57.5 #N/A 0.0 5.5 #N/A 6.3 #N/A (NTU) Mean 17.0 16.0 #N/A #N/A 2.9 #N/A 3.9 #N/A *Station operated seasonally

Water Quality Mean Values River Diversion Calpella Hopland Cloverdale* Jimtown* Diggers Bend System at Mirabel* Hacienda Bridge Johnsons Beach* 300 18.0 280 16.0 260 240 14.0 220 200 12.0 Turbidity

Temperature 180 10.0 160 140 8.0 120 100 6.0 80 Dissolved Oxygen, pH, Dissolved Oxygen,

Specific Conductivity, SpecificConductivity, 4.0 60 40 2.0 20 0 0.0 Specific Conductivity (µS/cm) Temperature (°F) Dissolved Oxygen (mg/L) pH Turbidity (NTU)

Russian River Water Quality (January 1 - February 18, 2021)

Calpella (East Fork Russian River)

Calpella Water Quality Trend 13.5 28

12.5 24

11.5 20 C) ° 10.5 16

9.5 12

8.5 8 Termperature ( Termperature DO (mg/L)DO pH and

7.5 4

6.5 0 1/1 1/5 1/9 2/2 2/6 1/13 1/17 1/21 1/25 1/29 2/10 2/14 2/18 2/22 DO pH Temperature

Calpella- Difference between Daily Maximum and Minimum for DO and pH 350 3.0

300 2.5

250 2.0 200 1.5 150 Flow (cfs) Flow 1.0 100

50 0.5

0 0.0 (mg/L) in DO andpH Difference 1/1 1/5 1/9 2/2 2/6 1/13 1/17 1/21 Flow1/25 pH 1/29 DO 2/10 2/14 2/18 2/22

Page 4 Russian River Water Quality (January 1 - February 18, 2021)

Hopland

Hopland Water Quality Trend 13.5 28

12.5 24

11.5 20 C) ° 10.5 16

9.5 12

8.5 8 DO (mg/L)DO pH and Termperature ( Termperature 7.5 4

6.5 0 1/1 1/5 1/9 2/2 2/6 1/13 1/17 1/21 1/25 1/29 2/10 2/14 2/18 2/22 DO pH Temperature

Hopland - Difference between Daily Maximum and Minimum for DO and pH 1200 3.0

1000 2.5

800 2.0

600 1.5 Flow (cfs) Flow 400 1.0

200 0.5

0 0.0 (mg/L) in DO andpH Difference 1/1 1/5 1/9 2/2 2/6 1/13 1/17 1/21 1/25 1/29 2/10 2/14 2/18 2/22 Flow pH DO

Jimtown Water Quality

Jimtown 13.5 28

12.5 24

11.5 20 C)

10.5 ° 16 9.5 12 8.5 8 DO (mg/L) pH DO and 7.5 Termperature ( Termperature

6.5 4

5.5 0 1/2 1/6 2/3 2/7 1/10 1/14 1/18 1/22 1/26 1/30 2/11 2/15 2/19 2/23 DO pH Temperature

Jimtown- Difference between Daily Maximum and Minimum for DO and pH 1400 1.0

0.9 1200 0.8

1000 0.7

0.6 800 0.5 600 Flow (cfs) Flow 0.4

400 0.3 0.2 200 0.1 Difference in DO (mg/L) inDO pH and Difference 0 0.0 1/1 1/5 1/9 2/2 2/6 1/13 1/17 1/21 Flow1/25 pH 1/29 DO 2/10 2/14 2/18 2/22

Page 5 Russian River Water Quality (January 1 - February 18, 2021)

Digger Bend

Digger Bend Water Quality Trend 28 13 24 12 20 11 C) ° 16 10

12 9

8 8 Termperature ( Termperature DO (mg/L)DO pH and

7 4

6 0 1/1 1/5 1/9 2/2 2/6 1/13 1/17 1/21 DO pH1/25 Temperature1/29 2/10 2/14 2/18 2/22

Digger Bend - Difference between Daily Maximum and Minimum for DO and pH 400 6.0 Stream Gauge 400 cfs maximum 350 exceeded during this time. 5.0 300 4.0 250

200 3.0

Flow (cfs) Flow 150 2.0 100 1.0 50

0 0.0 in(mg/L) DO andpHDifference 1/1 1/5 1/9 2/2 2/6 1/13 1/17 1/21 Flow1/25 pH 1/29 DO 2/10 2/14 2/18 2/22

Hacienda Bridge Water Quality

Hacienda Bridge 13.5 28

12.5 24

11.5 20 C) ° 10.5 16

9.5 12

8.5 8 Termperature ( Termperature DO (mg/L) pH DO and

7.5 4

6.5 0 1/1 1/5 1/9 2/2 2/6 1/13 1/17 1/21 1/25 1/29 2/10 2/14 2/18 2/22 DO pH Temperature

Hacienda Bridge - Difference between Daily Maximum and Minimum for DO and pH 2000 6.0

1800 5.0 1600

1400 4.0 1200

1000 3.0

Flow (cfs) Flow 800 2.0 600

400 1.0 200 Difference in DO (mg/L) inDO pH and Difference 0 0.0 1/1 1/5 1/9 2/2 2/6 1/13 1/17 1/21 1/25 1/29 2/10 2/14 2/18 2/22 Flow pH DO

Page 6 Russian River Fisheries Monitoring

Report on 2/18/21: Report on 2/18/21: Sonoma Water operates a fish counting station at a seasonal dam on the Russian River near the town of Forestville, CA. The Mirabel Dam video monitoring station closed for the season on January 23, 2021, but Sonoma Water continues to review video that was collected earlier in the season. Video is recorded at the east and west fish ladders. The counts below reflect totals completed for the full period of operation for the east fish ladder and up to January 11th for the west fish ladder. Surveys were conducted at five sites in the Upper Russian River to collect information on spawning salmonids and their redds. However, water visibility was too poor to observe salmonids or redds. Visibility ranged from 1.0 ft to 1.6 feet. During this time spawning was observed in Dry Creek. Salmonid Count at Mirabel Fish Ladder Most Recent Update Season Total Fish Counts (1/7/21-1/23/21) (9/1/20-1/23/21) Steelhead 283 457 Chinook 6 608 Coho 60 305 Unidentified Salmonid 0 27 Salmonid Redd and Spawner Survey

Location: Dry Creek Date: 2/15-2/18 Conditions: Spawning observed Spawner Survey Counts Most Recent Survey Season Survey Total Steelhead n/c 8 Chinook n/c 0 Coho n/c 0 Unidentified Salmonid n/c 5 Redd Survey Count: -

Precipitation Ukiah Municipal Airport (WBAN: 72590523275 (KUKI)) Date Range Cumulative (inches) Oct 1, 2020 - Feb 18, 2021 9.96 Last 7 Days* 0.94

Cumulative Precipitation Comparison of Current Year versus Historic Record 80

70

60

50

40

30 Precipitation (inches) Precipitation 20

10

0 1-Jul 8-Jul 7-Jan 3-Jun 1-Oct 8-Oct 1-Apr 8-Apr 4-Feb 2-Sep 9-Sep 3-Dec 5-Aug 15-Jul 22-Jul 29-Jul 5-Nov 4-Mar 6-May 14-Jan 21-Jan 28-Jan 10-Jun 17-Jun 24-Jun 15-Oct 22-Oct 29-Oct 15-Apr 22-Apr 29-Apr 11-Feb 18-Feb 25-Feb 16-Sep 23-Sep 30-Sep 10-Dec 17-Dec 24-Dec 31-Dec 12-Aug 19-Aug 26-Aug 12-Nov 19-Nov 26-Nov 11-Mar 18-Mar 25-Mar 13-May 20-May 27-May

Historical Maximum Historical Minimum Historical Average 10/1/2020 to Present

Global Forecast System Model 16-day Cumulative Precipitation Forecast

Date Range Forecasted Cumulative (inches) Feb 19 - Mar 6, 2021 0.5

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