Meeting Date:

January 27, 2005





David A. Berger,




General Manager

Line Item No.:



Prepared By:


Thomas Christensen

Cost Estimate:


General Counsel Approval:  N/A

Committee Recommendation:  N/A

CEQA Compliance:  N/A


IRRIGATION OF RIPARIAN VEGETATION:  For calendar year 2004, the supplemental watering of riparian restoration plantings resumed in April of 2004 at nine Monterey Peninsula Water Management District (District) riparian habitat restoration sites.  The following irrigation systems were irrigated April through October:  DeDampierre, Trail and Saddle, Scarlett, Begonia, Schulte South, Schulte Bridge, Schulte, All Saints, Valley Hills, and San Carlos.


            Water Use in Acre-Feet (AF)

            January - March 2004              0.00 AF

            April - June 2004                    2.50

            July – September 2004             6.11

            October – December 2004       0.85

            Total in 2004                            9.46 AF


MONITORING OF RIPARIAN VEGETATION:  During the months of May through October 2004, 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 2004 monitoring season to date show that non-irrigated sample cottonwoods and willows at Valley Hills became severely stressed from mid July to early October. Sample trees are not irrigated intentionally to see how they respond in a natural setting with groundwater extraction. However, the projects as a whole are irrigated and riparian vegetation is under threshold values. 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 26-A show impacts to water table elevations and riparian moisture stress in selected restoration sites in the lower Carmel Valley. On June 9, 2004, stream flow ceased in the Rancho Cañada area. Currently stream flow has returned and the Carmel River is flowing to the ocean.


The types of monitoring measurements made during May through October 2004 are as follows:


            Monitoring Measurement                                        


            Dawn leaf water potential          (See Exhibit 26-A for trends.) 

            Soil moisture (tensiometers)                                         

            Groundwater levels (monitoring wells)   (See Exhibit 26-B for trends.) 

            Groundwater pumping (production wells)                     




1. In-Channel Vegetation Management:  On October 5, 2004, District staff (Christensen, Bekker, Lyons, and Watters) modified a group of trees that fell across the Carmel River approximately 150 yards upstream of Rancho San Carlos Bridge. These trees were cut in large sections to reduce their potential for creating a debris dam that could divert winter flows into streambanks and lead to erosion and damage to infrastructure. The cut tree was left in the channel to provide "large wood habitat" consistent with state and federal resource agency requirements.


2. San Carlos Irrigation System:  On October 20, 2004, District staff (Christensen, Wheeler, Bekker, and Lyons) removed the temporary irrigation system from San Carlos Road Bridge downstream past Cal-Am's San Carlos Well (1,770 feet). This system is designed to water riparian plants on the bank of the river to help alleviate moisture stress associated with groundwater pumping. This system was removed because we have had significant rains and the river is working its way downstream.


3.  Carmel River In-Channel Vegetation Management:  District staff, (Mark Bekker, Matt Lyons, Thomas Christensen, and Larry Hampson) finished clearing vegetation in constricted areas in preparation for winter flows in the Carmel River. Work was completed at three sites along the Carmel River and extended for a total of 500 linear feet. The District operated under its Regional General Permit from the U.S. Army Corps of Engineers and an individual Streambed Alteration Agreement with the Department of Fish and Game.


4. Stream Bank Revegetation: District staff, (Thomas Christensen, Mark Bekker, and Paul Watters) helped a Carmel Valley resident, John Kenny, revegetate his exposed and eroding bank along the Carmel River. A total of 30 willows were planted. The District also provided information to Mr. Kenny on irrigation practices to help establish the vegetation. As the willows mature they should help prevent erosion and provide stability during higher flows.


5. Carmel River Watershed Council (CRWC) Meeting: On December 2, 2004, District staff (Christensen, Hampson, Watters, and Dettman) participated in a Technical Advisory Committee (TAC) meeting to help develop the CRWC's action plan. Topics of interest included sediment management, river flow increases, and habitat improvements.


6. Carmel River Advisory Committee Meeting: On December 16, 2004, District staff (Hampson, Christensen, and Bell) met with the Carmel River Advisory Committee. Tom Moss of Monterey County Water Resources Agency reported on the Carmel River Flood Elevation Study that is currently underway. Other topics of interest included an update on the San Clemente Dam seismic retrofit project and staff activities on the Carmel River.



26-A    Average Dawn Leaf Water Potential

26-B    Depth to Groundwater