Coastside County Water District

766 Main Street

Half Moon Bay, California  94019-1995

Phone: (650) 726-4405                               Fax: (650) 726-5245

Web: coastsidewater.org

 

Service Area

 

Coastside County Water District provides water to the City of Half Moon Bay and several unincorporated coastal communities in San Mateo County, including El Granada, Miramar, and Princeton by the Sea (Pillar Point Harbor).

 

System

 

Profile

 

Area Size

14 square miles

Service Population

 16,811

Number of Accounts

7,586

Number of SF RWS Connections

2

Connections To SF RWS Mains

Crystal Springs Intake and Stone Dam (Pilarcitos Lake)

Avg. Day Demand (mgd)

1.79

Avg. Day Purchases From SF RWS (mgd)

1.12

%  Demand Met With SF RWS Supplies

63%

Maximum Local Water Production (mgd)

0.5

Alternative Supply Sources

During a drought, local production is extremely low due to dependency on surface stream flows and a small watershed.

Interties With Other Agencies

None

Local Storage (mg)

8.0

Days of Storage

Approximately 3.0 days

 

Summary

 

Coastside County Water District has four water sources; (1) Pilarcitos Lake at Stone Dam, (2) Crystal Springs Reservoir, (3) the Pilarcitos Creek Infiltration Well Field, and (4) the Denniston (groundwater and surface water) Project. Water purchased from the SF RWS is supplied from two different raw water sources: Pilarcitos Lake at Stone Dam and Upper Crystal Springs Reservoir.


Raw water from Upper Crystal Springs Reservoir, Pilarcitos Lake at Stone Dam and the Pilarcitos Creek Infiltration Wells terminate at the Nunes Water Treatment Plant. Raw water from Denniston Creek and the Denniston Well Field terminate at the Denniston Water Treatment Plant.

 

 

Water Supply and Demand

 

Supply by Source

Actual
FY 15-16
(ccf)

Actual
FY 16-17
(ccf)

Actual
FY 17-18
(ccf)

Actual
FY 18-19
(ccf)

San Francisco Water

575,225

515,655

464,037

547,861

Local Groundwater

2,006

10,227

29,278

10,508

Surface Water

240,108

286,685

408,890

314,412

Recycled Water

0

0

0

0

Total

817,339

812,567

902,206

872,781

mgd equivalent

1.67

1.67

1.85

1.79

 

 

 

 

 

Demand by Sector

 

 

 

 

Residential

423,998

427,958

464,899

446,167

Commercial/Industrial

123,773

44,685

46,566

48,065

Other

95,609

90,426

165,626

266,457

Dedicated Irrigation

101,460

175,193

136,865

41,335

Non-Revenue Water

72,499

74,305

88,250

70,757

Total

817,339

812,567

902,206

872,781

mgd equivalent

 1.67

1.67

1.85

1.79

 

 

 

 

 

Per Capita Use

Actual
FY 16-17
(gpcpd)

Actual
FY 16-17
(gpcpd)

Actual
FY 17-18
(gpcpd)

Actual
FY 18-19
(gpcpd)

Residential

52

53

57

54

Gross

100

100

110

78

 

Facilities and Distribution

Treated Water Storage Reservoirs

 

Designation

Type

Capacity (mg)

Denniston

Steel

1.50

El Granada 1

Steel

0.20

El Granada 2

Steel

0.15

El Granada 3

Steel

0.25

Miramar

Steel

1.00

Carter Hill

Steel

0.40

Carter Hill

Steel

0.60

Carter Hill

Steel

1.50

Miramontes

Steel

0.40

Alves

Steel

2.00

 

 

 

Total

 

8.00

 

Surface Water Treatment Facilities

 

Designation

Capacity (mgd)

Nunes WTP

4.5

Denniston WTP

1.0

Total

5.5

 

Wells

 

Name

Capacity (gpm)*

Status

D1

25

Active

D2

 

Standby

D3

37

Active

D4

35

Active

D5

35

Active

D9

45

Active

P1**

40

November 1-March 31

P2**

 

Standby

P3**

 

Standby

P3A**

 

Standby

P4**

100

November 1-March 31
Standby

P4A**

200

November 1-March 31

P5**

65

November 1-March 31

Total

 

582

*Capacity is dependent on stream flows
**Surface water infiltration wells