28. QUARTERLY IRRIGATION PROGRAM AND RIPARIAN PROJECTS REPORT

Meeting Date: July 21, 2003 Budgeted: N/A

Program/Line Item No.: N/A

Staff Contact: Thomas Christensen Cost Estimate: N/A

General Counsel Approval: N/A

Committee Recommendation: N/A

CEQA Compliance: N/A

IRRIGATION OF RIPARIAN VEGETATION: The supplemental watering of riparian restoration plantings resumed in May of 2003 at nine Monterey Peninsula Water Management District (District) riparian habitat restoration sites. The following irrigation systems were irrigated May through June: DeDampierre, Trail and Saddle, Scarlett, Begonia, Schulte South, Schulte Bridge, Schulte, All Saints, and Valley Hills.

Water Use in Acre-Feet (AF)

January - March 2003 0.00 AF

April - June 2003 0.88

Year-to-date 0.88 AF

MONITORING OF RIPARIAN VEGETATION: During the months of May and June 2003, staff took weekly measurements of leaf water potential on target willow and cottonwood trees to provide an indication of plant water stress and corresponding soil moisture levels. Four locations (Rancho Cañada, San Carlos, Valley Hills, and Schulte) are monitored twice a month for pre-dawn leaf water potential. A total of 14 willows and 13 cottonwoods at these locations provide a data set of established and planted sample trees that are representative of trees in the Carmel River riparian corridor. Soil moisture measurements are conducted at three of these sites (San Carlos, Valley Hills, and Schulte) using tensiometers. Soil moisture values are measured at seven stations with 18-inch and 36-inch tensiometers in the soil column. Combined with monthly readings from the District’s array of monitoring wells and pumping records for large-capacity Carmel Valley wells in the Cal-Am system, the District’s monitoring provides insight into the status of soil moisture through the riparian corridor.

Current monitoring results for the 2003 monitoring season to date show that riparian vegetation is below threshold stress levels. Willows are considered severely stressed when values are 7.5 bars and above, while cottonwoods are considered severely stressed when values are 10.0 bars and above. The graphs in Exhibit 28-A show impacts to water table elevations and riparian moisture stress in selected restoration sites in the lower Carmel Valley. As of June 23, 2003 stream flow was still present in the Rancho Cañada area.

The types of monitoring measurements made during May through June 2003 are as follows:

Monitoring Measurement

Dawn leaf water potential (See Exhibit 28-A for trends.)

Soil moisture (tensiometers)

Groundwater levels (monitoring wells) (See Exhibit 28-B for trends.)

Groundwater pumping (production wells)

OTHER TASKS PERFORMED SINCE MARCH 2003 REPORT:

1. GIS Development Plan: On April 4, 2003, District staff (Osahan, Wheeler, Christensen, Hamilton, Lindberg, and Novack) met to discuss preparation of a GIS development plan. This plan will document existing District GIS operations, GIS goals for each division, and a needs assessment (software, hardware, and personnel) to carry out these goals.

2. Schulte South (Pryor) Irrigation Well Repair: Thomas Christensen, Riparian Projects Coordinator, worked with Carmel Valley Pump and Backflow Service to fix electrical problems at the Schulte South Well. Several breaker switches had failed and have now been replaced. This well, which is used to irrigate the District’s riparian plant nursery as well as riparian vegetation in the Pryor area, is now back online.

3. Carmel Valley Trail and Saddle Club Revegetation Project: On May 8, 2003, the District began a revegetation project to enhance the riparian corridor along property owned by the Carmel Valley Trail and Saddle Club. This project is also designed to prevent erosion by establishing riparian vegetation on the bare stream bank in this reach of the Carmel River.

4. Irrigation Installation at Red Rock Restoration Project: On May 19, 2003, District staff completed the final phase of the Red Rock Restoration Project by planting the upper terrace along River Meadows Road with riparian trees. In addition, 1,000 feet of new drip irrigation lines were installed to provide water for the riparian plantings.

5. Irrigation System Tune Up: District staff (Christensen, Lyons, Bekker, and Summers) tuned up nine of the District's irrigation systems by flushing lines, repairing leaks, and replacing over 600 clogged emitters. Irrigation systems are run to offset impacts to riparian vegetation associated with groundwater extraction and to help new restoration plantings become established.

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T. Christensen, 2 pages, 061903