CC 2017-08-22_09g Water Supply_Demand Update Aug 2017
MEMORANDUM
TO: CITY COUNCIL
FROM: SHANE TAYLOR, UTILITIES MANAGER
SUBJECT: MONTHLY WATER SUPPLY AND DEMAND UPDATE
DATE: AUGUST 22, 2017
RECOMMENDATION:
It is recommended the City Council receive and file the monthly Water Supply and
Demand Report.
SUMMARY OF ACTION:
This update reports the water supply and demand for July 2017. Current Lopez
Reservoir level and projected levels are provided in the attachments.
IMPACT ON FINANCIAL AND PERSONNEL RESOURCES:
Approximately two (2) hours of staff time is required to prepare the monthly report.
BACKGROUND:
On April 25, 2017, the City Council, by resolution, rescinded the Stage 1 Water
Shortage Emergency and related water conservation measures and restrictions. During
the public hearing the City Council requested staff to continue preparing the monthly
water supply and demand updates. The Council also urged citizens to remain
cognizant of how they use water, and that the previously adopted water saving
measures are still in effect.
In July, the City’s water use was 25% below June 2013. There is currently no required
reduction imposed by the State Water Resources Control Board. The City however, is
still required to report monthly statistics to the State. As a comparison for a single
month, water usage statistics were 15% higher in July 2017 than July 2016.
ANALYSIS OF ISSUES:
The United States Department of Agriculture (USDA) Drought Monitor, as of August 8,
2017 shows San Luis Obispo County as abnormally dry. Rainfall to date (July 1, 2017
to July 31, 2017) is 0 inches at the Corporation Yard gauge. Lopez Lake, as of August
11, 2017 is at 58% capacity (28,879 acre-feet of storage).
At the County of San Luis Obispo Board of Supervisors meeting on May 23, 2017, the
Board rescinded the drought emergency proclamation. However, as recommended by
Item 9.g. - Page 1
CITY COUNCIL
MONTHLY WATER SUPPLY AND DEMAND UPDATE
AUGUST 22, 2017
PAGE 2
the Zone 3 Advisory Board, the Board of Supervisors kept the Low Reservoir Response
Plan in place. This will allow carryover water to be available until March 30, 2018 to all
contractors. The new water year began on April 1, 2017 and the current total available
supply from Lopez is 2,290 acre-feet, the City’s normal entitlement, plus 1,249 acre-feet
of carryover. In addition the City has 1,323 acre-feet of ground water entitlement from
the Santa Maria Basin and 200 acre-feet from the Pismo Formation.
Based on the projected water use of 2,500 acre-feet, the City will meet the demand in
water year 2017/18, using only 50% of current supply.
ADVANTAGES:
No advantages noted at this time.
DISADVANTAGES:
No disadvantages noted at this time.
ALTERNATIVES:
Not applicable at this time.
ENVIRONMENTAL REVIEW:
No environmental review is required for this item.
PUBLIC NOTIFICATION AND COMMENTS:
The Agenda was posted at City Hall and on the City’s website in accordance with
Government Code Section 54954.2.
Attachment:
1. Lopez Reservoir Storage Projections
2. Lopez Reservoir Storage Projections based on 16/17 Hydrology
3. LRRP Projection
4. Zone 3 – Lopez Project – Monthly Operations Report
Item 9.g. - Page 2
3.176.720.004.160.002.590.003.6214.430.001.690.00 #N/A0.020.370.722.060.002.004.006.008.0010.0012.0014.0016.0018.0020.004,0009,00014,00019,00024,00029,00034,00039,00044,00049,00012/1/20151/1/20162/1/20163/1/20164/1/20165/1/20166/1/20167/1/20168/1/20169/1/201610/1/201611/1/201612/1/20161/1/20172/1/20173/1/20174/1/20175/1/20176/1/20177/1/20178/1/20179/1/201710/1/201711/1/201712/1/2017Monthly Precipitation (in)Storage(AF)Notes:• For "Dry Months" (April ‐ October), projected increases and/or decreases in storage estimated to mimic conditions from 2015.• For "Wet Months" (November ‐ March), projected storage declines assume LRRP annual downstream release of 3,800 AFY and deliveries of 4,077 AFY.• For "Wet Months", projected storage increases based on historic trends from actual storm data for the period of 12/1993 through 6/2011.• Storage projection for "Wet Months" assume that unsaturated conditions exist.• Rainfall projection provided by www.LongRangeWeather.com, and updated 2/1/2017. Evaporation included in storage projection.• Past 3 Year Avg. Projection uses historic daily capacity changes averaged from 2014, 2015, 2016• Actual precipitation is the total of the previous month.• Actual precipitation is the rainfall measured by FRM at Lopez Rec Area.Lopez Reservoir Storage Projections(precipitation scenario source: www.LongRangeWeather.com)Actual PrecipitationProjected PrecipitationActual StorageProjected StoragePast 3 Year Avg. ProjectionStorage Without Carryover15,000 AF10,000 AFAttachment 1Item 9.g. - Page 3
2.591.813.6212.499.061.691.570.24024681012140.010,000.020,000.030,000.040,000.050,000.060,000.0Monthly Precipitation (in)Storage (AF)DateLopez Storage Projection based on 16/17 HydrologyActual PrecipitationActual StorageProjected Storage20,000 AFStorage w/o Carryover49,000 AFNote: Storage Projection is based on Water Year 16/17 municipaland downstream releases, rainfall, and evaporation.Attachment 2Item 9.g. - Page 4
2.591.813.6212.499.061.691.570.24024681012140.05,000.010,000.015,000.020,000.025,000.030,000.035,000.0Monthly Precipitation (in)Storage (AF)DateEXHIBIT C ‐ LRRP ProjectionActual PrecipitationActual StorageProjected Storage20,000 AFStorage w/o CarryoverNote: Storage Projection is based on Water Years 14/15 and 15/16 municipaland downstream releases, rainfall, and evaporation.Attachment 3Item 9.g. - Page 5
San Luis Obispo County Flood Control and Water DistrictZone 3 - Lopez Project - Monthly Operations ReportJuly, 20170.00Note: Deliveries are in acre feet. One acre foot = 325, 850 gallons or 43, 560 cubic feet. Safe yield is 8,730 acre feet."Year to Date" is January to present for State water, April to present for Lopez deliveries, and July to present for rainfall.758.31April to Present0.00Arroyo Grande2290Lopez Dam OperationsLake Elevation (full at 522.37 feet)496.71Storage (full at 49200 acre feet)29086Rainfall0Downstream Release (4200 acre feet/year)387.29Spillage (acre feet)0This MonthYear to Date981.430.001249.20219.87Entl.SurplusUsage3539.20TotalLopez Water Deliveries196.63Oceano CSD303840.5057.371143.50255.73Grover Beach800240.2066.941040.20326.68Pismo Beach8961834.20180.062730.2033.32CSA 12241499.6012.45740.60451.395050.0035.5869.966.310.0000.00State Water Deliveries1570.6745304663.70536.699193.70545.38684.9619.72Total ContractorDifference (feet)-25.66% Full59.1%Comments:Reservoir is currently operated under the Low Reservoir Response Plan. Reservoir is above 20,000 AF therefore no reduction in entitlements.Surplus water shown is actually "Carry Over" water as designated in the LRRP and updated per BOS May 2, 2017 Declaration of Surplus. 1) Oceano supplied State Water to Canyon Crest via Arroyo Grande's Edna turn out. A totalof 2.58 AF delivered to Canyon Crest was added to Oceano's State Water usage this month and 2.58 AF was subtracted from Arroyo Grande's usage this month.April to Present Lopez Entitlement+Surplus Water Usage050100150200250Jan '17 Feb '17 Mar '17 Apr '17 May '17 Jun '17 Jul '17Acre FeetAGGBOCSDPBCSA12January to Present State Water Usage020406080100120140Jan '17 Feb '17 Mar '17 Apr '17 May '17 Jun '17 Jul '17Acre FeetOCSDPBCSA12SanMigSan Miguelito58.4111013.41This Month%TotalJanuary to PresentUsageThis Month% of Annual RequestUsage% of Annual Request219.87Total Water Deliveries This Month57.3766.94180.0618.7613.41556.41Annual Request0.00Usage0.000.000.000.00%0.000.000.000.000.00758.31196.63255.73326.6833.321570.670.001002.00SWP DeliveriesSWP DeliveriesChange in Storage145125.28942.55This Month Stored State Water0.0%9.6%21.4%18.9%17.2%8.4%24.6%20.1%12.0%5.2%4.5%0.0%89.4%9.0%50.9%0.0%0.0%11.8%17.1%2.9%79.6%12.2%53.1%0.0%0.0%0.0%0.0%0.0%0.0%0.0%0.0%0.0%0.0%33.1%64.9%32.0%36.5%13.8%34.7%0.0%EntitlementSurplusUsage%Usage%EntitlementSurplusUsage%813.08Last Month Stored State WaterMonday, August 07, 2017Page 1 of 1Report printed by:AdminData entered by:D. SpiegelAttachment 4Item 9.g. - Page 6