Water Department
McNally Canal Notice of Dispute
On October 13, 2000, Inyo County served on the Los Angeles Department of Water and
Power the following Notice of Dispute regarding the operation of the McNally Canals in the
Laws area. The notice was prepared in accordance with the dispute resolution provisions of
the Inyo County/Los Angeles Water Agreement. LADWP is expected to respond to the Notice of
Dispute in mid-November.
NOTICE OF DISPUTE
NATURE AND SUBJECT OF DISPUTED ISSUES
Issue 1
The first issue in dispute centers on the obligations of the City of Los Angeles Department of Water and Power ("LADWP") to manage its groundwater pumping and surface water conveyance facilities in order to meet the vegetation management commitments of the "Agreement Between the County of Inyo and the City of Los Angeles and its Department of Water and Power on a Long Term Groundwater Management Plan for Owens Valley and Inyo County" ("Agreement"). (The Agreement is Appendix 4 hereto.)
The subject of the dispute in Issue 1 is:
Whether operation of one or both of the McNally canals should be commenced during this runoff year, and continued as necessary, until perennial vegetation cover in parcels 52, 82 and 85 in the Laws area has recovered to baseline conditions.
Issue 2
The second issue in dispute centers on whether a change in canal operations by LADWP must first be approved by the Standing Committee.
The subject of the dispute in Issue 2 is:
Whether LADWP’s announced intent to continue reductions in the frequency of the operation of the McNally canals is a permanent change in the operation of the McNally canals that requires prior Standing Committee approval under the Agreement.
INTRODUCTION
At its meeting on September 14, 2000, the Inyo County/Los Angeles Standing Committee ("Standing Committee") was in disagreement as to a resolution of the following two issues which appeared as Item 4c on its meeting agenda:
Whether one or both of the McNally canals should be operated during the remainder of this runoff year to promote water table recovery, allow for vegetation recovery, and to supply the remaining Type E and E/M project irrigation requirements in the Laws area; and,
Whether LADWP’s announced intent to reduce the frequency of the operation of the McNally canals is a permanent change in the operation of the McNally canals that requires Standing Committee approval under the Agreement.
(A memorandum dated September 14, 2000, which was included in the September 14, 2000 agenda of the Standing Committee in regard to Item 4c is Appendix 5 hereto. A map of the Laws area showing the Upper and Lower McNally canals, the parcels where vegetation change monitoring has been conducted, and irrigated lands is Figure 1 (p. 2a) of this document.)
Section XXVI of the Agreement provides that disagreements over any matter arising out of the Agreement may be submitted to a specified dispute resolution process. (See Agreement, Section XXVI, p.p. 53-58.)
The Standing Committee is currently considering the adoption of dispute resolution procedures that will augment the provisions of Section XXVI of the Agreement. At its meeting on July 6, 2000, the Standing Committee agreed that in the event that a dispute arises prior to the formal adoption of such procedures, "Draft 6 of the Inyo County/Los Angeles Standing Committee Dispute Resolution Procedures" dated June 14, 2000, which was presented to the Standing Committee at its meeting on June 16, 2000, will govern any such dispute. The County of Inyo ("County") presents this dispute in accordance with the provisions of the draft procedures.
Evidence in Support of the County's Position in this Dispute
The evidence and testimony in support of the County’s position on Issues 1 and 2, which are the subjects of this dispute, are presented in this document and in the following appendices:
Vegetation Information for Dispute Resolution Regarding Operation of the McNally Canals,Vegetation Information for Dispute Resolution Regarding Operation of the McNally Canals, Sara J. Manning, Ph.D., Vegetation Scientist, Inyo County Water Department (October 11, 2000).
Laws Area Hydrology and Canal Operations,Laws Area Hydrology and Canal Operations, Robert F. Harrington, Ph.D., Hydrologist, Inyo County Water Department (October 11, 2000).
Synopsis of Soil Water/Groundwater Relations in the Laws Area and the Owens Valley, by Aaron L. Steinwand, Ph.D., CPSSc., Soils Scientist, Inyo County Water Department (October 11, 2000).
Agreement Between the County of Inyo and the City of Los Angeles and its Department of Water and Power on a Long Term Groundwater Management Plan for Owens Valley and Inyo County (including its technical appendix, the Green Book).
Memorandum dated September 14, 2000, to the Inyo County/Los Angeles Standing Committee from the Inyo County Standing Committee Representatives, which was included in the September 14, 2000 agenda of the Standing Committee in regard to Item 4c.
Drought Recovery Policy, Inyo County/Los Angeles Standing Committee.
Letter to Greg James, Director Inyo County Water Department from Gene L. Coufal, Manager, Aqueduct Business Group, LADWP, dated May 26, 2000.
Hereinafter, Appendix 1 is referred to as "Manning," Appendix 2 is referred to as "Harrington," Appendix 3 is referred to as "Steinwand," Appendix 4 is referred to as the "Agreement" or the "Green Book," as appropriate, and Appendix 6 is referred to as the "Drought Recovery Policy." Appendices 5 and 7 are referenced by their full titles.
(LADWP is in possession of copies of the Agreement and the Green Book; therefore these documents comprising Appendix 4 are not attached hereto. In addition, data and reports referenced in Appendices 1, 2 and 3 have been previously provided to LADWP; therefore, these data and reports are not attached hereto. However, the Agreement, the Green Book and/or any data or reports referenced in the appendices will be provided to LADWP upon request, and will be presented to any mediator/arbitrator(s) involved in this dispute.)
Appendices 1, 2 and 3 each present "expert" testimony together with the facts, data and information that supports each author’s testimony. The name, address, phone number, curriculum vitae of the author of each Appendix, and a statement of qualifications of each author to testify as an expert, is presented at the end of each Appendix.
BACKGROUND
The Agreement
In 1991, the City of Los Angeles, LADWP and the County settled nearly two decades of litigation concerning the environmental impacts of LADWP’s groundwater pumping and other water related operations in the Owens Valley, and concerning the County’s right to regulate such activities. The settlement was memorialized in the Agreement and in a related environmental impact report ("EIR").
Legal challenges to the adequacy of the EIR were presented by the California Department of Fish and Game, the California State Lands Commission, the Sierra Club and the Owens Valley Committee. In 1997, the challenges were resolved through the approval by all parties of a Memorandum of Understanding. On June 13, 1997, the Agreement (in the form of a "Stipulation and Order for Judgment") was entered as a final order of the Inyo County Superior Court. (Although the Agreement was not finalized until 1997, as allowed by the courts, LADWP and the County began managing the water resources of the Owens Valley in accordance with the provisions of a draft version of the Agreement in 1989, and in accordance with the final version of the Agreement in 1991.)
The Agreement provides that the Standing Committee, consisting of elected and appointed officials from the City of Los Angeles, LADWP and the County, and a Technical Group, consisting of staff representatives from LADWP and the County, will represent the City of Los Angeles, LADWP and the County in implementing the goals and principles of the Agreement. (Agreement, Section II, p. 6.)
Overall Management Under the Agreement
In regard to the management of water resources, the Agreement provides:
The overall goal of managing the water resources within Inyo County is to avoid certain described decreases and changes in vegetation and to cause no significant effect on the environment which cannot be acceptably mitigated while providing a reliable supply of water for export to Los Angeles and for use in Inyo County. (Agreement, Section III.A, p. 10.)
The technical appendix to the Agreement, a document called the "Green Book"
(see
Agreement, Section III.E, p. 12) (the Green Book is included in Appendix 4), clarifies the
overall goal by stating:
This means that groundwater pumping and changes in surface water management practices will be managed with the goal of avoiding significant decreases and changes in Owens Valley vegetation from conditions documented in 1984 to 1987, and of avoiding other significant environmental impacts. (Green Book, Section I.A, p. 1.) (Italics added for emphasis.)
A vegetation inventory conducted by LADWP between 1984 and 1987 was used to document the Agreement’s baseline vegetation conditions on approximately 227,000 acres of the floor of the Owens Valley. For the purpose of the inventory, and for the establishment of baseline conditions, the inventoried area was broken into over 2,000 vegetation parcels of more or less homogeneous vegetation units. The baseline for each vegetation parcel is the inventoried percent live vegetation cover and the percent composition for each species present in each parcel. (Green Book, Section II, p.p. 34-45.)
Using LADWP’s 1984-1987 inventory, the vegetation was classified into one of five types (A through E) for management purposes under the Agreement. (See Agreement, Section III, p.p. 8-9; and Green Book, Section II.A.1 and 2, p.p. 34-39.) The vegetation was classified into types based on the following criteria:
Type A: vegetation with evapotranspiration approximately equal to precipitation (approximately 150,347 acres),
Type B: shrub communities with evapotranspiration greater than precipitation (approximately 10,390 acres),
Type C: grassland/meadow vegetation communities with evapotranspiration greater than precipitation (approximately 42,013 acres),
Type D: riparian vegetation (approximately 5,580 acres), and
Type E: vegetation on lands where water is supplied (approximately 18,830 acres).
Management of Vegetation
In regard to the groundwater dependent grassland/meadow (Type C) which comprises the dominant vegetation within the vegetation parcels in Laws that is of concern in Issue 1, the Agreement recognizes that:
The communities comprising this classification exist because of high groundwater conditions, natural surface water drainage, and/or surface water management practices in the area, i.e., conveyance facilities, wet year water spreading, etc. (Agreement, Section II.A, p. 9.) (Italics added for emphasis.)
The Agreement’s goal for the management of this vegetation is:
…to manage groundwater pumping and surface water management practices so as to avoid causing significant decreases in live vegetation cover, and to avoid causing a significant amount of vegetation comprising either the Type B, C, or D classification to change to vegetation in a classification type which precedes it alphabetically (for example, Type D changing to either Type C, B, or A vegetation). (Agreement, Section IV.A, p. 14.) (Italics added for emphasis.)
Management of Groundwater Pumping. The Agreement and the Green Book contain provisions for an extensive monitoring program designed with the intent of identifying water management caused problems before significant impacts occur. In general, under the Agreement, with regard to Types B and C vegetation, groundwater pumping is managed based upon measurements of the "water balance" at permanent monitoring sites. LADWP groundwater wells are linked to these monitoring sites. If it is projected that the estimated amount of soil
water available to the vegetation at a monitoring site is less than the estimated water needs of the vegetation for a growing season ("soil water deficit"), LADWP’s wells linked to that monitoring site are turned off, and once turned off, wells cannot be turned on until soil water at the relevant monitoring site has recovered to a specified level. (Agreement, Section V.A, p.p. 20-23; Green Book, Section I.B.2, p.p. 3-13.)
Management of Surface Water Management Practices. In regard to the management of "surface water management practices," for Types B and C vegetation, the Green Book states:
Should water balance calculations project that less soil water will be available in an area of Type B or C vegetation than is required by the vegetation, and…[I]f the projected soil water deficit is attributable to changes in surface water management practices, such action as is feasible and necessary will be taken to avoid significant decreases and changes in the vegetation. (Green Book, Section I.B.2.b, p. 14.) (Italics added for emphasis.)
Moreover, concerning Types B, C and D vegetation, the Agreement states in regard to the management of "surface water management practices:"
The Department shall continue to operate canals in accordance with its practices from 1970 (past practices have included taking canals out of service for maintenance and for operational purposes). However, any permanent change in canal operations, compared to past practices, shall be subject to prior Standing Committee approval. (Agreement, Section IV.A, p. 16.) (Italics added for emphasis.)
Annual Operations Plan. Under the Agreement, LADWP is to prepare an "Annual Operations Plan" which sets forth its proposed operations and pumping for each runoff year (April 1st through March 31st). The plan, and the pumping program, must be consistent with the goals and principles of the Agreement. (Agreement, Section V.D, p.p. 23-24.)
Drought Recovery Policy
In response to a prolonged drought and in recognition of the experimental nature of the management and mitigation techniques set forth in the Agreement, in 1990, the Standing Committee adopted a "Drought Recovery Policy." (A copy of the policy is Appendix 6 hereto.) The goal of the policy "…is that soil moisture within the rooting zone recover to a degree sufficient so that the vegetation protection goals of the Agreement are achieved." The policy provides that during the then current drought, and during a period of recovery, "[T]he Standing Committee will establish annual pumping programs based on an evaluation of current conditions, including soil type, vegetation conditions, the results of studies pertaining to vegetation recovery, and compliance with the goals of the Agreement." The Drought Recovery Policy is still in effect during the recovery period following the drought.
Vegetation Change Monitoring
The Green Book provides that "[V]egetation transects are included within the Green Book to serve two purposes: 1) to estimate transpiration from a monitoring site, and 2) for use in determining whether vegetation has decreased or changed significantly from the previous cover." (Italics added for emphasis.) The Green Book states that if there is suspected vegetation change, vegetation transects may be established to monitor vegetation changes. The Green Book provides that at such vegetation change monitoring sites, plant cover shall be measured by the line-point technique, and the 1984-1987 vegetation inventory baseline is to be used to determine whether vegetation cover or species composition has changed. (See Green Book, Box I.C.1.a.ii, p. 22.)
At a Technical Group meeting conducted on March 6 and 8, 1991, County representatives suggested that additional monitoring using line-point transects be established to monitor vegetation recovery following the then existing drought. (See Summary of Technical Group meeting conducted on March 6 and 8, 1991, p.p. 3-4.) Subsequently, a cooperative study proposal incorporating such line-point vegetation change monitoring was developed by the County and reviewed by LADWP. During the summer of 1991, the line-point monitoring was commenced. (Manning, p. 1.)
On April 15, 1992, the Technical Group agreed that the line-point vegetation monitoring would continue to be conducted, and that the line-point monitoring would be considered a joint effort of LADWP and the County. (See Summary of Technical Group meeting conducted on April 15, 1992, p. 4.) (Copies of the summaries of the Technical Group meeting conducted on March 6 and 8, 1991, and the summary of the Technical Group meeting conducted on April 15, 1992, are in LADWP’s possession; therefore, copies of these summaries are not attached hereto. However, copies of these referenced summaries will be provided to LADWP upon request, and will be presented to any mediator/arbitrator(s) involved in this dispute.) Since 1992, the line-point vegetation monitoring program has been annually conducted at up to 100 vegetation parcels employing fundamentally the same monitoring protocol each year. (Manning, p.p. 2-3.)
SPECIFIC ISSUES IN DISPUTE
AND THE COUNTY’S POSITION ON EACH ISSUE
STATEMENT OF ISSUE 1
Whether operation of one or both of the McNally canals should be commenced during this runoff year, and continued as necessary, until perennial vegetation cover in parcels 52, 82 and 85 in the Laws area has recovered to baseline conditions.
THE COUNTY’S POSITION ON ISSUE 1
Vegetation Declined in Parcels 52, 82 and 85 in Laws
Eighteen of the line-point vegetation monitoring parcels are located in the Laws area. Of the 3,737 acres of groundwater dependent vegetation in the Laws area, the eighteen Laws line-point vegetation parcels encompass 719 acres. (Manning, p. 3, and Table 2.) A map identifying the vegetation parcels that have been monitored in Laws under the line-point vegetation change monitoring program is presented as Figure 2 (p. 7a) of this document. (Figure 2 is a true and correct copy of Figure 2 presented in the Manning report at p. 6.)
Table 1 presents the baseline percentage of perennial vegetation cover (shown in the column titled "DWP"), and the subsequently measured percentages from 1991 to the present within each of the eighteen parcels monitored in Laws. The shaded boxes on the table indicate parcels where the vegetation cover is statistically significantly below baseline. (The table is a true and correct copy of Table 5, presented in the Manning report at p.p. 9-10.)
Table 1
Average perennial cover in all Laws parcels monitored by Inyo County Water Dept. (INY) from 1991 through 2000. Baseline perennial cover is listed under DWP. t-tests were performed and significant differences from baseline are denoted with an asterisk. Results that are significantly lower than baseline are shaded; results that are significantly greater than baseline appear in bold.
% COVER, PERENNIALS ONLY |
|||||||||||
| Parcel | DWP | INY91 | INY92 | INY93 | INY94 | INY95 | INY96 | INY97 | INY98 | INY99 | INY00 |
| LAW030 | 23.08 |
12.00* |
16.25* |
21.16 |
27.25 |
32.07 |
|||||
| LAW040 | 14.67 |
9.17* |
11.75 |
9.25 |
16.75 |
13.83 |
9.43 |
||||
| LAW052 | 27.83 |
4.16* |
4.91* |
7.75* |
8.83* |
4.50* |
|||||
| LAW062 | 21.44 |
1.50* |
3.00* |
5.50* |
9.71* |
11.21* |
18.07 |
13.50* |
|||
| LAW063 | 11.50 |
4.54* |
2.44* |
5.31* |
5.50* |
7.92 |
8.75 |
11.37 |
6.31* |
15.13 |
9.88 |
| LAW065 | 9.67 |
1.75* |
4.08* |
3.58* |
7.58 |
6.00 |
5.28* |
5.07* |
7.92 |
7.00 |
|
| LAW076 | 6.50 |
2.80* |
9.79 |
||||||||
| LAW078 | 51.71 |
7.50* |
20.21* |
24.57* |
44.50 |
55.41 |
|||||
| LAW082 | 16.50 |
5.50* |
2.58* |
5.83* |
4.33* |
5.14* |
|||||
| LAW085 # | 30.64 |
5.11 |
5.79 |
17.92 |
5.50 |
18.75 |
13.79 |
9.78 |
10.87 |
12.50 |
19.00 |
| LAW104 | 9.00 |
5.58* |
|||||||||
| LAW107 | 46.86 |
22.08* |
13.08* |
18.08* |
26.25* |
24.66* |
34.83 |
38.00 |
62.25* |
61.71* |
|
| LAW109 | 18.50 |
3.54* |
|||||||||
| LAW110 | 35.17 |
11.33* |
10.89* |
20.64* |
29.14 |
40.88 |
38.81 |
59.41* |
63.71* |
||
| LAW112 | 20.33 |
16.33 |
14.50* |
20.33 |
13.83* |
20.50 |
13.67* |
11.57* |
|||
| LAW120 | 25.92 |
14.18* |
12.58* |
19.17* |
11.58* |
29.08 |
28.83 |
29.50 |
41.66* |
33.17 |
41.29* |
| LAW122 | 59.56 |
58.92 |
58.08 |
43.00* |
57.58 |
68.25* |
64.33 |
65.58 |
88.25* |
56.29 |
|
| LAW137 | 20.42 |
8.63* |
15.25 |
12.43* |
16.00 |
18.36 |
21.86 |
16.50 |
|||
# = DWP baseline data not available, so statistical analyses not performed.
As shown on the table, perennial vegetation cover in all eighteen parcels has declined below baseline at some time since line-point vegetation monitoring commenced in 1991. In most parcels, perennial vegetation cover has recovered from its lowest levels to baseline or above (but in some of these recovered parcels, vegetation cover has again declined below baseline). However, vegetation cover in three parcels located in proximity to the Lower McNally Canal, and to each other, (parcels 52, 82 and 85) had declined below baseline in 1991, and has never recovered to baseline. Therefore, as of this year, vegetation cover in these parcels remains statistically significantly below baseline. (The statistical significance of the decline of perennial vegetation in parcel 85 has not been calculated because only the percentage of the overall perennial baseline cover is available; the actual inventory data upon which the overall percentage baseline cover was derived by LADWP is not available from LADWP.)
The Depth to Water Declined Under Parcels 52, 82, and 85 in Laws
As shown on Table 2 below, the depth to the water table beneath parcels 52, 82 and 85 in the Laws area has declined, risen, and declined since these parcels were inventoried in 1987. (The table is a true and correct copy of Table 3, presented in the Manning report at p. 7.) The depth to water information presented in the table below was developed by interpolating shallow monitoring well data collected in April of each year. (Harrington, at p.p. 4-8, concurs that the depth to water under these parcels is estimated to have varied as stated, and these estimates are consistent with nearby monitoring wells.(Harrington, p.p. 4-8.)
Table 2
Depth to Water (In Meters) Beneath Monitored Laws Parcels
baseline |
|||||||||||||||||
PCL |
avg (85-87) |
1985 |
1986 |
1987 |
1988 |
1989 |
1990 |
1991 |
1992 |
1993 |
1994 |
1995 |
1996 |
1997 |
1998 |
1999 |
2000 |
LAW030 |
6.74 |
4.21 |
7.83 |
8.18 |
10.77 |
9.86 |
9.87 |
10.97 |
9.82 |
9.78 |
10.06 |
9.94 |
10.03 |
9.96 |
9.13 |
8.29 |
8.92 |
LAW040 |
5.94 |
3.67 |
7.31 |
6.82 |
11.09 |
9.01 |
7.97 |
9.02 |
9.00 |
8.93 |
10.88 |
11.15 |
9.35 |
10.16 |
8.97 |
5.00 |
6.94 |
LAW052 |
2.92 |
3.13 |
2.47 |
3.16 |
8.96 |
8.29 |
6.68 |
8.10 |
8.14 |
8.91 |
6.61 |
7.63 |
5.84 |
6.93 |
6.39 |
2.79 |
4.86 |
LAW062 |
3.92 |
2.83 |
4.20 |
4.75 |
8.17 |
8.71 |
8.82 |
9.06 |
9.07 |
9.00 |
7.82 |
8.87 |
6.07 |
7.94 |
6.35 |
3.45 |
5.38 |
LAW063 |
4.06 |
2.63 |
4.63 |
4.92 |
8.02 |
7.47 |
8.21 |
8.42 |
8.40 |
8.33 |
7.92 |
8.81 |
6.59 |
8.25 |
7.17 |
3.75 |
5.74 |
LAW065 |
3.14 |
2.10 |
3.52 |
3.80 |
6.57 |
5.73 |
6.25 |
6.15 |
6.31 |
6.40 |
6.66 |
7.47 |
5.83 |
7.19 |
6.62 |
3.91 |
5.51 |
LAW076 |
2.73 |
2.15 |
3.49 |
2.55 |
5.37 |
4.65 |
5.48 |
5.25 |
5.50 |
5.62 |
5.14 |
5.73 |
4.24 |
5.35 |
5.03 |
2.80 |
4.00 |
LAW078 |
2.28 |
2.27 |
2.11 |
2.44 |
5.50 |
7.10 |
6.77 |
7.02 |
7.01 |
7.97 |
5.73 |
6.56 |
4.16 |
5.40 |
4.59 |
2.24 |
3.40 |
LAW082 |
3.95 |
3.95 |
4.09 |
3.81 |
9.16 |
10.57 |
10.47 |
10.92 |
10.31 |
11.00 |
7.61 |
8.82 |
6.43 |
7.75 |
6.89 |
3.28 |
4.86 |
LAW085 |
4.21 |
3.70 |
5.06 |
3.85 |
8.01 |
9.94 |
10.24 |
9.87 |
9.25 |
9.83 |
7.28 |
7.98 |
5.85 |
6.82 |
5.98 |
3.71 |
4.36 |
LAW104 |
4.87 |
3.85 |
5.72 |
5.05 |
8.84 |
10.37 |
11.45 |
10.62 |
9.74 |
9.22 |
7.67 |
7.92 |
6.64 |
7.34 |
6.78 |
5.16 |
5.46 |
LAW107 |
1.99 |
1.78 |
2.36 |
1.81 |
3.95 |
5.17 |
5.40 |
5.55 |
5.55 |
5.83 |
4.40 |
4.72 |
3.15 |
3.84 |
3.45 |
1.82 |
2.47 |
LAW109 |
2.82 |
2.29 |
3.11 |
3.06 |
5.29 |
5.34 |
5.80 |
5.80 |
5.64 |
5.63 |
5.25 |
5.48 |
4.30 |
4.78 |
4.55 |
3.28 |
3.91 |
LAW110 |
2.80 |
2.45 |
3.34 |
2.61 |
4.66 |
4.98 |
5.64 |
5.64 |
5.42 |
5.37 |
4.78 |
5.01 |
3.91 |
4.48 |
4.50 |
3.14 |
3.65 |
LAW112 |
3.80 |
3.03 |
4.56 |
3.81 |
6.77 |
7.99 |
9.37 |
8.16 |
7.49 |
7.01 |
6.15 |
5.81 |
4.77 |
5.54 |
4.77 |
3.82 |
4.01 |
LAW120 |
4.17 |
4.03 |
4.80 |
3.67 |
6.97 |
7.26 |
8.10 |
7.84 |
6.95 |
7.45 |
6.55 |
6.30 |
5.48 |
6.50 |
5.79 |
4.79 |
5.23 |
LAW122 |
2.96 |
2.77 |
3.68 |
2.41 |
3.46 |
3.70 |
4.74 |
4.36 |
4.53 |
4.45 |
4.55 |
3.84 |
3.16 |
3.42 |
3.54 |
2.82 |
3.31 |
LAW137 |
4.96 |
4.48 |
4.70 |
5.71 |
8.59 |
9.58 |
9.58 |
9.74 |
9.41 |
9.56 |
8.38 |
8.63 |
6.52 |
6.91 |
7.08 |
5.68 |
5.88 |
The Decline in the Depth to Water Under Parcels 52, 82 and 85
is Attributable to LADWP’s Operations
As set forth in the preceding section, since the vegetation inventory of parcels 52, 82 and 85 in Laws was conducted in 1987, the water table significantly declined in the Laws area, including beneath these parcels. (Harrington, Figures 2-6, p.p. 4-8). The water table decline in the Laws area was caused by LADWP’s groundwater pumping (Harrington, p. 11 and Tables 3 and 4), and recovery of the water table was reduced and delayed by reductions in the frequency of the operation of the McNally canals. (Harrington, p. 16-23.)
It is important to note that once the water table in the Laws area has declined, recovery of the water table is primarily caused by the operation of the McNally canals. In other areas of the Owens Valley, most groundwater recharge results from percolation from stream channels. In the Laws well field, however, regression analysis of shallow monitoring well hydrographs and evaluation of the water budget for the Laws area indicates that recharge from the unlined McNally canals, water spreading activities associated with the operation of the canals, and groundwater pumping are the primary variables influencing fluctuations in the water table. (Harrington, p.p. 8-24, Green Book, Tables 10, 11, and 13.)
The amount of recharge provided by the McNally canals is not known precisely because a rigorous water balance for the Laws area has not been conducted. It is estimated that seepage from the McNally canals recharges 5,325 acre feet per year when they are operated (Green Book, Table IV.7 and equation IV.4); however, this amount ranges from negligible to over 10,000 acre feet per year, varying with the rate and duration of canal operation. Water spreading activities add an additional volume of recharge, the amount of which ranges from negligible to over 20,000 acre feet, depending on the extent and duration of water spreading activities. (Green Book, Table IV.10, p. 165-166.)
Runoff-years 1996 and 1997 were 131% and 120% of normal runoff years respectively. It has been LADWP’s past practice from 1970 to 1995 to divert approximately 10,000 to 20,000 acre feet of water into the McNally canals under such runoff conditions (Harrington, Figure 8, p. 17.) However, in 1996, no diversions were undertaken, and in 1997, only 4,892 acre feet were diverted into the canal system. Additionally, during runoff years 1999 and 2000, (approximately 97% and 91% of normal runoff respectively), no water was diverted into the McNally canals. In contrast, it was LADWP’s practice from 1970 to 1995 to divert approximately 4,000 to 19,000 acre feet into the canals under such runoff conditions. (Harrington, Figure 8, p. 17.) Thus, it appears that since 1996, LADWP has deviated from its past practices.
In regard to the change in the frequency of the operation of the McNally canals, LADWP’s decision to deviate from its past surface water management since 1996 has been estimated to result in a reduction in the water table elevation in the Laws area of between approximately 0.45 meters and 1.85 meters below where it would have been at the end of runoff year 2000 had the canals been operated in accordance with past practices. This decline varies within the Laws area depending on proximity to the McNally canals and pumping wells. (Harrington, p.p. 17-23.)
The Decline of Vegetation in Parcels 52, 82 and 85 was
Caused by the Decline in the Depth to Water Under these Parcels
Since the beginning of the line-point vegetation monitoring program in 1991, the data have documented significant declines in perennial groundwater dependent vegetation cover throughout the Owens Valley in areas where the water table has declined. This conclusion is supported by the fact that in control areas of similar vegetation, where there has been little or no decline in water tables, the data show that the perennial vegetation cover has not significantly declined. (Manning, p. 1.) This difference between vegetation response to water table decline in well field areas versus control parcels is documented on Figure 2a which summarizes results from control and well field parcels. (The figure is a true and correct copy of Figure 1, presented in the Manning report at p. 2).
Figure 2a
Average change in cover relative to baseline for parcels monitored 1991-1999. Parcels are grouped as control (not affected by pumping or changes in surface water management practices) and well field, which include the two categories: DRP (unrecovered well field parcels) and DRP free (well field parcels exhibiting recovery of water table and perennial cover.)
Asterisks denote statistically significant changes from baseline (p < 0.05)
using the t-test. As shown on Figures 3, 4 and 5, and the text accompanying each figure,
perennial vegetation cover in parcels 52, 82 and 85 in Laws declined in relation to the
decline of the water table under these parcels. Moreover, these figures show that the
depth to water, as of April 2000, is below the rooting zone (2 meters) of the dominant
meadow vegetation in all three parcels. (Figures 3, 4 and 5 are true and correct copies of
Figures 8, 14 and 15 presented in the Manning
report, and the language accompanying each figure is a true and correct copy of language
appearing on p. 11 (LAW052) and p. 12 (LAW082 and LAW085) of the Manning report.)
Figure 3
LAW052 (Figure 8): From 1988 to 1998, the water table was below the 1985-1987 baseline
average depth of 2.92m and also below 4m. In 1999, the water table briefly reached the
baseline average depth, but by 2000, it had dropped over 2m and thus fell below 4m.
Perennial cover has been significantly below baseline in all years this parcel has been
monitored, including 1999 and 2000. Grass cover has dropped substantially and tumbleweed
is dominant in wet years.
Figure 4
LAW082 (Figure 14): The water table beneath this parcel was below baseline (3.95m) and
below 4m from 1988 to 1998. Perennial cover was significantly below baseline in all years
this parcel was monitored (1991, 1997-2000). Although the water table rose above baseline
between April 1998 and spring 1999, perennial cover remained significantly below baseline
in 1999. Between 1999 and 2000, the water table dropped below 4m and 2000 perennial cover
was also significantly less than baseline. Despite being mapped by DWP as a rabbitbrush
meadow, grass cover as recorded with transects has been extremely low. Tumbleweeds
proliferate in wet years.
Figure 5
LAW085 (Figure 15: The water table beneath this parcel was below baseline (4.21m) from
1988 to 1998. In 1999, the water table rose to 3.71m, then it declined to 4.36m in 2000.
Perennial cover was below baseline in all years this parcel was monitored (1991 through
2000). Because original transect data for this parcel do not exist, statistics were not
used to analyze the perennial cover decreases.
The Decline of the Water Table Under Parcel 85 has Caused a
Soil Water Deficit in this Parcel
A fundamental management precept of the Green Book is that if there is inadequate soil water available to Types B and C vegetation (a projected "soil water deficit"), the vegetation will adversely decrease and/or change. Therefore, if there is a projected soil water deficit at a permanent monitoring site, pumping is discontinued from wells that are linked to the monitoring site to promote soil water recovery by allowing the water table to recover to a level where water moves by capillary action from the water table into the rooting zone of the vegetation. (Green Book, Section I. B.2, p.p. 3-13.)
As documented by Steinwand at p.p. 8-10, presently there is a measurable soil water deficit at a permanent monitoring site, L2, located in the northern portion of parcel 85 near well V001G. (See in Figure 1 hereto for the location of well V001G.) L2 is also located near the southern portion of parcel 82.
If the Operation of the McNally Canals Commences this Runoff
Year,
Water Tables Under Parcels 52, 82 and 85 will be Raised
Statistical analyses show that for every 1,000 acre feet of water that is diverted from the Owens River into the McNally canals, the water table will rise between approximately 0.151 and 0.426 feet. (Harrington, p. 23.) (As much as 41,500 acre feet annually have been diverted into the McNally canals under LADWP’s past practices from 1970 to the present. (Harrington, Table 1, p. 3.) As projected by Harrington, this recovery would vary depending on the location within the Laws area, but in areas such as parcels 52, 82 and 85, which are in proximity to the McNally canals and to water spreading, there would be relatively large rises in the water table if the McNally canals are operated and no groundwater pumping occurs. (It should be noted that a portion of the surface water diverted into the McNally canals is used to supply irrigated lands in the Laws area, and some of the water returns to the river/aqueduct system by groundwater flow and through the Laws return ditch.)
Raising the Water Table Under Parcels 52, 82 and 85 Will Cause an
Increase in the Soil Water
As described by Steinwand on p.p. 2-3, as the water table rises, the soil water within the rooting zone of this vegetation will increase once the soil water is capable of being supplied via capillarity from the water table. Further, as discussed by Steinwand on p.p. 3, water supplied to the root zone from the water table is a much larger and more lasting component of the soil water balance than is soil water derived from precipitation. The effect of precipitation on the soil water balance is ephemeral and, typically, precipitation is exhausted by the end of the growing season and seldom do appreciable quantities of soil water carry over until next growing season.
If the Water Tables Under Parcels 52, 82 and 85 are Raised, the Perennial Vegetation Cover Within these Parcels Will Have an Opportunity to Recover to Baseline
Analysis of the relationship between water table and perennial cover shows that higher water tables are significantly correlated with higher perennial cover. This relationship was statistically significant for Laws parcels 62, 63, 78, 107, 110, 120, 122 and 137. (Manning, p.p. 32-36.) If the water table beneath parcels 52, 82 and 85 is raised high enough to recharge soil water in the root zone of the groundwater dependent vegetation, the analysis by Manning concludes that improved perennial cover conditions will result.
The Agreement and the Green Book Require the
Commencement of the Operation of the McNally Canals
As noted above, if there is a risk of a significant decrease or change in vegetation, and if the potential decrease or change is attributable to a change in surface water management practices, the Green Book requires that:
…such action as is feasible and necessary will be taken to avoid significant decreases and changes in the vegetation. (Green Book, Section I.B.2.b, p. 14.) (Italics added for emphasis.)
Also as noted above, the Drought Recovery Policy has a similar goal, "…that soil moisture within the rooting zone recover to a degree sufficient so that the vegetation protection goals of the Agreement are achieved."
It has been shown above that the lowering of the water tables under parcels 52, 82 and 85 is attributable to LADWP’s groundwater pumping in combination with LADWP’s changes in the frequency of the operation of the McNally canals. Further, the decline in the water table under these parcels caused the perennial vegetation cover within these parcels to decline significantly below baseline conditions. Moreover, the perennial vegetation in these parcels has been below baseline for at least ten years.
It is both feasible and necessary to commence operation of the McNally canals this runoff year to promote recovery of the water tables under parcels 52, 82 and 85 to provide an opportunity for the perennial vegetation cover in these parcels to recover to achieve the goals of the Agreement. The County requested that the McNally canals be operated this runoff year as part of LADWP’s Annual Operations Plan. LADWP objected, and stated that operation of the McNally canals this runoff year would be inconsistent with past practices; however, LADWP presented no reason why it would be infeasible to commence operation of the canals this year.
If the operation of the canals is not commenced this runoff year, water levels under these parcels will remain below the rooting zone of the vegetation within the parcels, and the vegetation cover will continue to remain significantly below baseline conditions. If not this year, when, if ever, will the affected vegetation be given an opportunity to recover? This question is
especially relevant since LADWP’s groundwater pumping in the Laws area continues to further lower water tables in the area, and since LADWP intends to continue its reductions in the frequency of the operation of the McNally canals. (See the County’s position on Issue 2 presented below which is incorporated herein as if fully set forth at this point.)
As shown above, perennial vegetation cover that has declined below baseline conditions due to a lowering of the water table beneath the vegetation has recovered to baseline once the water table has been allowed to recover to supply water to the vegetation for a sufficient period of time. Therefore, it is reasonable to assume that the best chance for recovery of perennial vegetation in parcels 52, 82 and 85 is to promote water table recovery to improve soil moisture conditions in the rooting zone of the vegetation in these parcels.
The recovery of the water tables should not be further delayed. The vegetation within parcels 52, 82 and 85 has been degraded for a long time. A further delay may jeopardize the recovery of this vegetation. (See Figures 3, 4 and 5 above.)
Conclusion—Issue 1
The goal of the Agreement is to avoid significant decreases and changes to vegetation.
It is both feasible and necessary to commence operation of the McNally canals this runoff
year to avoid significant decreases and/or changes in the vegetation within parcels 52, 82
and 85 and to achieve the goals of the Agreement. The operation of the McNally canals
should be commenced this year.
STATEMENT OF ISSUE 2
Whether LADWP’s announced intent to continue reductions in the frequency of the operation of the McNally canals is a permanent change in the operation of the McNally canals that requires prior Standing Committee approval under the Agreement.
THE COUNTY’S POSITION ON ISSUE 2
The Agreement Requires Prior Standing Committee Approval of
Any Permanent Change in Canal Operations
The Agreement is very specific in regard to permanent changes in canal operations. Section IV.A of the Agreement provides:
The Department shall continue to operate canals in accordance with its practices from 1970 (past practices have included taking canals out of service for maintenance and for operational purposes). However, any permanent change in canal operations, compared to past practices, shall be subject to prior Standing Committee approval. (Agreement, p. 16.) (Italics added for emphasis.)
LADWP’s Actual Operation of the McNally Canals Has Deviated
from Past Surface Water Management Practices
Section I of the Green Book provides:
When reference is made to changes in surface water management practices, changes will be determined in comparison with past practices since 1970. (Green Book, p. 1)
As noted in the County’s position on Issue 1 (which is incorporated herein as if fully set forth at this point), LADWP has already deviated from its past surface water management practices of the McNally canals by reducing the frequency of canal operations. (Consistent with the Green Book and the Agreement, past practices are the frequency and volume of diversions into the McNally canals since 1970, and the distribution and use of the diverted water.)
LADWP has Announced its Intent to Continue to Reduce the
Frequency of the Operation of the McNally Canals
During the May 2, 2000 meeting of the Technical Group, LADWP representatives stated that the McNally canals have been, and will be, operated less frequently than in the past. In addition, this change was reiterated in a letter dated May 26, 2000, from Gene L. Coufal, Manager, Aqueduct Business Group, LADWP to Greg James, Director, Inyo County Water Department. (A copy of the letter is Appendix 7 hereto.) In regard to change in the operation of the McNally canals, the letter stated on page 2: "[I]n your letter you make the point that recent use of the McNally Canals is different from historic use. While this is undoubtedly true for a variety of reasons (extended drought, loss of Mono Basin exports, etc)…."
LADWP has stated that the McNally canals will only be operated in a 140 percent or higher runoff year. At the September 14, 2000 Standing Committee meeting, LADWP representatives contended that such a change in the frequency of the operation of the canals did not constitute a permanent change in the operation of the canals because LADWP has not changed its policy in regard to the operation of the canals.
During the September 14th Standing Committee meeting, LADWP representatives explained that LADWP’s policy has been, and remains, to operate the McNally canals only when the amount of water in LADWP’s river/aqueduct system requires water to be removed from the system to avoid overloading the system. LADWP representatives explained that, when such conditions occur, LADWP diverts water into the McNally canals from the Owens River (and perhaps spreads water from the canals in the Laws area) in order to reduce the amount of water in its river/aqueduct system. LADWP representatives noted that because of reduced flows in the Owens River resulting from reduced diversions from the Mono Basin, under its existing policy, the McNally canals have not been, and will not be, operated as frequently as when the river flows were higher due to diversions from the Mono Basin.
Changes in the Frequency of the Operation of the McNally
Canals Affect
Groundwater Dependent Vegetation in the Laws Area
The Agreement clearly acknowledges that Type C vegetation (grasslands/meadow) and Type D vegetation (riparian/marshland) exist, "…because of high groundwater conditions, natural surface water drainage, and/or surface water management practices in the area, i.e., conveyance facilities, wet year spreading, etc." (Agreement, Section II.C and D, p. 9.) (Italics added for emphasis.) The goal for these two vegetation types is to, "…manage groundwater pumping and surface water management practices so as to avoid significant decreases in vegetation cover…." (Agreement, Section IV. A, p. 14.) (Italics added for emphasis.)
As is set forth in the County’s position on Issue 1, there is no question that Type C vegetation in the Laws area is actually dependent on the surface water management practices of the McNally canals. Groundwater in the Laws area is primarily replenished by the operation of the McNally canals. Groundwater levels under such Type C vegetation will be lower if the McNally canals are not operated as frequently as in the past.
The Requirement that the Standing Committee Approve Changes
in Canal Operations is an Important Tool for Achieving
the Vegetation Protection Goals of the Agreement
It is significant that the provision requiring Standing Committee approval of permanent changes in canal operations is incorporated into the Agreement’s section on "Vegetation Management." The intent of the Agreement in requiring prior Standing Committee approval of a permanent change in canal operations is to prevent unilateral operational changes by LADWP that could negatively affect the vegetation of the Owens Valley, and to insure that the Standing Committee has considered the potential impacts of the proposed changes in relation to achieving the vegetation protection (and other) goals of the Agreement.
LADWP’S Intent to Continue its Past Reductions in the Frequency
of the McNally Canal Operation is a Permanent Change
in Canal Operations that Requires
Prior Approval of the Standing Committee
LADWP contends that because its policy has not changed in regard to the operation of the McNally canals, there is no permanent change in canal operations. The County believes that it is irrelevant that LADWP’s policy has not changed, the relevant issue under the Agreement is whether there will be a permanent physical change in the operation of the McNally canals. If there is such a permanent change, prior Standing Committee approval of the change is required by the Agreement.
There has been, and will be, a reduction in the frequency of the canal operations, and as a result, a decrease in the net amount of surface water supplied to the Laws area for groundwater recharge, maintenance of riparian vegetation adjacent to the McNally canals and irrigation. Such a physical change will result in a long-term reduction in the amount of surface water that passes
through the canals and a reduction of groundwater recharge in the Laws area. Therefore, LADWP’s long-term reduction in the frequency of the operation of the McNally canals that has occurred, and will occur, requires Standing Committee approval.
Conclusion—Issue 2
One of the Agreement’s primary means of managing surface water management practices is the requirement that changes in the operation of conveyance facilities, such as the McNally canals, upon which Types C and D vegetation are dependent, will not be altered unless the consequences have been first fully considered by the Standing Committee. LADWP’s long-term reduction in the frequency of the operation of the McNally canals is a permanent change in canal operations. This permanent change in canal operations requires Standing Committee approval.
THE COUNTY’S PROPOSED RESOLUTION OF THE DISPUTED ISSUES
The County requests that the two issues in dispute be resolved as follows:
Issue 1
That it be determined that the operation of one or both of the McNally canals should be commenced during this runoff year, and continued as necessary, until perennial vegetation cover in parcels 52, 82 and 85 in the Laws area has recovered to baseline conditions.
Issue 2
That it be determined that:
LADWP’s long-term reduction in the frequency of the operation of the McNally canals is a permanent change in canal operations.
Under the Agreement, this permanent change in canal operations requires prior Standing Committee approval.
PROPOSED DATE, TIME AND LOCATION FOR
STANDING COMMITTEE MEETING TO CONSIDER
RESOLUTION OF THE DISPUTED ISSUES
The County proposes that the Standing Committee convene on or before December 4, 2000, at 10:00 a.m. in Independence or Bishop, California, to conduct a hearing on the matters at issue in this dispute.
END