Loading...
CC 2016-01-26_09g Water Supply and Demand Update_NovDec2015 MEMORANDUM TO: CITY COUNCIL FROM: GEOFF ENGLISH, DIRECTOR OF PUBLIC WORKS BY: SHANE TAYLOR, PUBLIC WORKS SUPERVISOR – UTILITIES SUBJECT: MONTHLY WATER SUPPLY AND DEMAND UPDATE DATE: JANUARY 26, 2016 RECOMMENDATION: It is recommended the City Council receive and review the monthly Water Supply and Demand Report. IMPACT ON FINANCIAL AND PERSONNEL RESOURCES: The cost to provide the report is limited to staff time, which equates to approximately $500. BACKGROUND: The severe drought continues to impact the City’s water supply and demand. As a result, the City Council declared a Stage 1 Water Shortage Emergency on May 26, 2015. This monthly update on the current supply and demand statistics will provide the Council with the data required to make decisions related to Emergency Water Shortage Restrictions and Regulations. ANALYSIS OF ISSUES: The severe drought continues, however, a new rainfall year began in July and we have received 5.4” of rain as of December 31, 2015. Lopez Lake is currently at 28% capacity (13,835 AF of storage). The Low Reservoir Level Response Plan (LRRP) has been enacted. At the Zone 3 Advisory Board meeting on May 21, 2015, the Board recommended that the deliveries from the Water Treatment Plant be reduced by 10% starting April 1, 2015. This was done in advance of the Lake reaching 15,000 AF of storage, which is the automatic reduction trigger. Lopez Lake reached the 15,000 AF storage level around November 1, 2015. In November, the City’s water use was 41% below November 2013. In December, the City’s water use was 42% below December 2013. This significantly exceeds the Item 9.g. - Page 1 CITY COUNCIL MONTHLY WATER SUPPLY AND DEMAND UPDATE JANUARY 26, 2016 PAGE 2 reduction requirement imposed by the State Water Resources Control Board for Arroyo Grande of 28%. The Lopez supply for water year 2015/16 for Arroyo Grande is 2,942 AF, which includes 883 AF of carry-over water. Based on the projected water demand of 2,300 AF, we expect to be able to meet the demand in water year 2015/16 with minimal groundwater pumping. 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 in front of City Hall on Thursday, January 21, 2016. The Agenda and staff report were posted on the City’s website on Friday, January 22, 2016. Attachments: 1. November/December 2015 Water Supply and Demand Charts 2. Lopez Reservoir Storage Projections 3. Zone 3 - Lopez Project - Monthly Operations Report Item 9.g. - Page 2 Ci t y  of  Ar r o y o  Gr a n d e  Wa t e r  Su p p l y  an d  De m a n d  Up d a t e ‐No v e m b e r  2015 Cu m u l a t i v e  Ra i n f a l l  fr o m  Ju l y  1,  20 1 5  to  No v e m b e r  30 t h :  3. 8  in c h e s L o p e z  La k e   Nov‐15WY 15/16 Year to DateRemaining Allocated Supply La k e  El e v a t i o n  (f u l l  at  52 2 . 3 7  ft ) 466.79 St o r a g e  (f u l l  at  49 , 2 0 0  AF ) 14,160.3 St o r a g e  ‐   Pe r c e n t  Fu l l 29% St a t u s Enacted Cu r r e n t  En t i t l e m e n t  Re d u c t i o n   10% De l i v e r i e s  (A F ) 136.921,476.33 1,465.82  Gr o u n d w a t e r Nov‐15Calendar Year to DateRemaining Entitlement SM G B  Pr o d u c t i o n  (A F ) 3 . 9 4 2 . 6 1 , 2 8 0 . 4 Pi s m o  Fo r m a t i o n  Pr o d u c t i o n  (A F ) 0 . 0 4 4 . 0 N A Ci t y  SM G B  av e r a g e  we l l  le v e l s  fo r  No v e m b e r  20 1 5  were 0.23 feet higher than in November 2014.  To t a l  Ci t y  De m a n d  (A F ) No t e :  Gr o u n d w a t e r  en t i t l e m e n t  an d  pr o d u c t i o n  da t a  is  ba s e d  on the calendar year. No v e m b e r  20 1 3 23 7 . 3 No v e m b e r  20 1 5 14 0 . 8 % Di f f e r e n c e  fr o m  20 1 3 ‐41 % WY  20 1 3 / 1 4  YT D 2, 3 0 1 . 7 WY  20 1 5 / 1 6  YT D 1, 5 4 3 . 2   % Dif f e r e n c e  fr o m  WY  20 1 3 / 1 4 ‐33 % No t e :    Th e  Wa t e r  Ye a r  (W Y )  fo r  wa t e r  de m a n d  is  fr o m  Ap r i l  to  Ma r c h . No t e :  Pr e c i p i t a t i o n  da t a  fr o m  AG  Co r p  Ya r d  St a t i o n  No .  17 7 . 1  fr o m  Ju l y  19 6 6  ‐   No v e m b e r  30 ,  20 1 5 . Water Supply Ra i n f a l l Pr e d i c t e d  Su p p l y  an d  De m a n d Wa t e r  De m a n d No t e :  Th e  Wa t e r  Ye a r  (W Y )  fo r  Lo p e z  La k e  is  fr o m  Ap r i l  to  March. The actual amount of storage in Lopez at the end of November 2015 was 14,178 AF;  ho w e v e r ,  th e  st o r a g e  am o u n t  an d  st o r a g e  pe r c e n t a g e  ab o v e  were adjusted to account for the 17.67 AF of stored State Water Project water in the lake. No t e :  Th es e  pr o d u c t i o n  fo r e c a s t s  co n t a i n  pr e l i m i n a r y  es t i m a t e s  of water production and draft predictions of future production based on historical  av e r a g e s .   0. 0 5. 0 10 . 0 15 . 0 20 . 0 25 . 0 30 . 0 35 . 0 JU L A U G S E P O C T N O V D E C J A N F E B M A R A P R M A Y J U N Rainfall (in.) Cu m u l a t i v e  Ra i n f a l l Av e r a g e  Ra i n f a l l  Ye a r  (1 9 9 5 ‐19 9 6 ) We t t e s t  Ra i n f a l l  Ye a r  (1 9 9 7 ‐19 9 8 ) Dr i e s t  Ra i n f a l l  Ye a r  (2 0 1 3 ‐20 1 4 ) 20 1 5 ‐20 1 6  Ra i n f a l l  as  of  No v e m b e r  30 ,  20 1 5 2, 0 6 1   88 1   1, 3 2 3   16 0 2, 3 0 0    ‐  1, 0 0 0  2, 0 0 0  3, 0 0 0  4, 0 0 0  5, 0 0 0 AF WY  20 1 5 / 1 6  Pr e d i c t e d  Su p p l y  an d  De m a n d Lo p e z  En t i t l e m e n t  (‐10 % ) Lo p e z  Su r p l u s SM G B  Gr o u n d w a t e r  Al l o c a t i o n Pi s m o  Fo r m a t i o n  Gr o u n d w a t e r WY  20 1 5 / 1 6  Ta r g e t  De m a n d 01,0002,0003,0004,0005,0006,000 050 10 0 15 0 20 0 25 0 30 0 35 0 Apr‐14 May‐14 Jun‐14 Jul‐14 Aug‐14 Sep‐14 Oct‐14 Nov‐14 Dec‐14 Jan‐15 Feb‐15 Mar‐15 Apr‐15 May‐15 Jun‐15 Jul‐15 Aug‐15 Sep‐15 Oct‐15 Nov‐15 Dec‐15 Jan‐16Supply Remaining (AF) Deliveries/Capacity (AF) Wa t e r  Su p p l y ,  Demand and Delivery Chart Lo p e z  Wa t e r  Av a i l a b l e  (A F ) Groundwater Allotment Available Lo p e z  Wa t e r  De l i v e r y Pismo Formation Water Pumped (AF) SM G B  Wa t e r  Pu m p e d  (A F ) Predicted Lopez Water Delivery Pr e d i c t e d  Pi s m o  Fo r m a t i o n  Pr o d u c t i o n Predicted SMGB Production Av e r a g e  De m a n d  20 1 1 ‐20 1 3  (A F ) Updated: 1/11/2016ATTACHMENT 1 Item 9.g. - Page 3 Ci t y  of  Ar r o y o  Gr a n d e  Wa t e r  Su p p l y  an d  De m a n d  Up d a t e ‐De c e m b e r  2015 Cu m u l a t i v e  Ra i n f a l l  fr o m  Ju l y  1,  20 1 5  to  De c e m b e r  31 s t :  5. 4  in c h e s L o p e z  La k e   Dec‐15WY 15/16 Year to DateRemaining Allocated Supply La k e  El e v a t i o n  (f u l l  at  52 2 . 3 7  ft ) 465.90 St o r a g e  (f u l l  at  49 , 2 0 0  AF ) 13,834.9 St o r a g e  ‐   Pe r c e n t  Fu l l 28% St a t u s Enacted Cu r r e n t  En t i t l e m e n t  Re d u c t i o n   10% De l i v e r i e s  (A F ) 131.841,608.17                               1,333.98                                 Gr o u n d w a t e r Dec‐15Calendar Year to DateRemaining Entitlement SM G B  Pr o d u c t i o n  (A F ) 0 . 1 4 2 . 7 1 , 2 8 0 . 3                                    Pi s m o  Fo r m a t i o n  Pr o d u c t i o n  (A F ) 0 . 0 4 4 . 0 N A Ci t y  SM G B  av e r a g e  we l l  le v e l s  fo r  De c e m b e r  20 1 5  were unavailable at the time this report was prepared.  To t a l  Ci t y  De m a n d  (A F ) No t e :  Gr o u n d w a t e r  en t i t l e m e n t  an d  pr o d u c t i o n  da t a  is  ba s e d  on the calendar year. De c e m b e r  20 1 3 22 6 . 6                                                                                                                                                                                                                                    De c e m b e r  20 1 5 13 1 . 9                                                                                                                                                                                                                                    % Di f f e r e n c e  fr o m  20 1 3 ‐42 % WY  20 1 3 / 1 4  YT D 2, 5 2 8 . 2                                                                                                                                                                                                                            WY  20 1 5 / 1 6  YT D 1, 6 7 5 . 1                                                                                                                                                                                                                              % Di f f e r e n c e  fr o m  WY  20 1 3 / 1 4 ‐34 % No t e :    Th e  Wa t e r  Ye a r  (W Y )  fo r  wa t e r  de m a n d  is  fr o m  Ap r i l  to  Ma r c h . No t e :  Pr e c i p i t a t i o n  da t a  fr o m  AG  Co r p  Ya r d  St a t i o n  No .  17 7 . 1  fr o m  Ju l y  19 6 6  ‐   De c e m b e r  31 ,  20 1 5 . Water Supply Ra i n f a l l Pr e d i c t e d  Su p p l y  an d  De m a n d Wa t e r  De m a n d No t e :  Th e  Wa t e r  Ye a r  (W Y )  fo r  Lo p e z  La k e  is  fr o m  Ap r i l  to  March. The actual amount of storage in Lopez at the end of December 2015 was 13,847 AF;  ho w e v e r ,  th e  st o r a g e  am o u n t  an d  st o r a g e  pe r c e n t a g e  ab o v e  were adjusted to account for the 12.12 AF of stored State Water Project water in the lake. No te :  Th e s e  pr o d u c t i o n  fo r e c a s t s  co n t a i n  pr e l i m i n a r y  es t i m a t e s  of water production and draft predictions of future production based on historical  av e r a g e s .   0. 0 5. 0 10 . 0 15 . 0 20 . 0 25 . 0 30 . 0 35 . 0 JU L A U G S E P O C T N O V D E C J A N F E B M A R A P R M A Y J U N Rainfall (in.) Cu m u l a t i v e  Ra i n f a l l Av e r a g e  Ra i n f a l l  Ye a r  (1 9 9 5 ‐19 9 6 ) We t t e s t  Ra i n f a l l  Ye a r  (1 9 9 7 ‐19 9 8 ) Dr i e s t  Ra i n f a l l  Ye a r  (2 0 1 3 ‐20 1 4 ) 20 1 5 ‐20 1 6  Ra i n f a l l  as  of  De c e m b e r  31 ,  20 1 5 2, 0 6 1   88 1   1, 3 2 3   16 0 2, 3 0 0    ‐  1, 0 0 0  2, 0 0 0  3, 0 0 0  4, 0 0 0  5, 0 0 0 AF WY  20 1 5 / 1 6  Pr e d i c t e d  Su p p l y  an d  De m a n d Lo p e z  En t i t l e m e n t  (‐10 % ) Lo p e z  Su r p l u s SM G B  Gr o u n d w a t e r  Al l o c a t i o n Pi s m o  Fo r m a t i o n  Gr o u n d w a t e r WY  20 1 5 / 1 6  Ta r g e t  De m a n d 01,0002,0003,0004,0005,0006,000 050 10 0 15 0 20 0 25 0 30 0 35 0 Apr‐14 May‐14 Jun‐14 Jul‐14 Aug‐14 Sep‐14 Oct‐14 Nov‐14 Dec‐14 Jan‐15 Feb‐15 Mar‐15 Apr‐15 May‐15 Jun‐15 Jul‐15 Aug‐15 Sep‐15 Oct‐15 Nov‐15 Dec‐15 Jan‐16Supply Remaining (AF) Deliveries/Capacity (AF) Wa t e r  Su p p l y ,  Demand and Delivery Chart Lo p e z  Wa t e r  Av a i l a b l e  (A F ) Groundwater Allotment Available Lo p e z  Wa t e r  De l i v e r y Pismo Formation Water Pumped (AF) SM G B  Wa t e r  Pu m p e d  (A F ) Predicted Lopez Water Delivery Pr e d i c t e d  Pi s m o  Fo r m a t i o n  Pr o d u c t i o n Predicted SMGB Production Av e r a g e  De m a n d  20 1 1 ‐20 1 3  (A F ) Updated: 1/11/2016 Item 9.g. - Page 4 ATTACHMENT 2 Item 9.g. - Page 5 Item 9.g. - Page 6 AT T A C H M E N T 3 It e m 9. g . - Pa g e 7 It e m 9. g . - Pa g e 8