B. Description of Proposed Boundary Modification

1. Short Description

   Define and identify the non-adjudicated areas of the Riverside-Arlington subbasin (8-02.03).
2. Type of basin boundary revision

   • Jurisdiction Internal
3. Provide a narrative overview of the boundary modification request and how the resulting modification would affect likelihood of sustainable management.

   The Riverside-Arlington Subbasin (8-02.03) is partially exempt from portions of SGMA because of the 1969 Western-San Bernardino Judgment. The adjudicated portions of the basin are jointly reported by two Court-appointed Watermasters, one from San Bernardino Valley Municipal Water District and the other from Western Municipal Water District. This Basin Boundary Request is to specifically identify the non-adjudicated areas of the Riverside-Arlington Subbasin, the areas that are not exempt from SGMA. In 2012, Western's Board of Directors, following years of stakeholder input and public meetings, adopted the Arlington Basin Groundwater Management Plan with the expressed purpose of identifying sound objectives, protocols and mechanisms for effective groundwater management for the provision of safe, reliable and sustainable water supplies in the Basin. The clear definition of the non-adjudicated areas within the larger Riverside-Arlington subbasin as defined by Bulletin 118 will ensure clear understanding of the Arlington Basin boundaries under SGMA.

   Attachment(s):
4. List the existing basin(s)/subbasin(s) to be modified by this request

   • 8-002.03 UPPER SANTA ANA VALLEY - RIVERSIDE-ARLINGTON
5. Provide the proposed name for the new basin(s) or subbasin(s)

   Upper Santa Ana Valley - Arlington Basin

C. Initial Notification and Combination of Requests

1. Was an initial notification submitted to the Department?

   Yes
   List of submitted initial notification for the selected basin(s)/subbasin(s).

   Local Agency	Potential Basin(s)/Subbasin(s)
   San Bernardino Valley Municipal Water District	8-002.04 UPPER SANTA ANA VALLEY - RIALTO-COLTON , 8-002.03 UPPER SANTA ANA VALLEY - RIVERSIDE-ARLINGTON , 8-002.07 UPPER SANTA ANA VALLEY - YUCAIPA
   Western Municipal Water District Of Riverside	8-002.03 UPPER SANTA ANA VALLEY - RIVERSIDE-ARLINGTON

2. Does this application include a combination of requests?

   Yes

   If yes, describe:

   Both the San Bernardino Valley Municipal Water District and Western Municipal Water District are requesting that the Riverside-Arlington Subbasin be separated along the 1969 Western-San Bernardino Judgment boundary. The Riverside Basin remains adjudicated. The Arlington Basin is a non-adjudicated area under SGMA.

D. Required Documents for All Modifications

1. A copy of the statutory or other legal authority under which the requesting agency was created with specific citations to the provisions setting forth the duties and responsibilities of the agency.

Attachment(s):

• WMWD Articles of Incorporation.pdf (843kB) Uploaded on 03/28/2016 at 10:57AM

2. A copy of the signed resolution adopted by the requesting agency formally initiating the boundary modification request process.

Attachment(s):

• WMWD Resolution 2937_Arlington Boundaries.pdf (184.4kB) Uploaded on 03/28/2016 at 11:00AM

3. A map of adequate scale (no greater than 1:24,000; e.g., 1:10,000 is not acceptable) showing the proposed modified basin boundary in relation to the existing Bulletin-118 basin boundary and the local agencies that are within or bordering the existing and proposed basin.

Attachment(s):

• Arlington Basin Map.pdf (828.6kB) Uploaded on 03/30/2016 at 02:03PM

4. A GIS shapefile of the proposed modified groundwater basin boundaries. Download Existing B118 basin shape file | DWR Spatial Data Standards

Attachment(s):

• NewProposedBasin.zip (10.3kB) Uploaded on 03/30/2016 at 03:00PM

5. A GIS shapefile of the political boundaries of any affected or adjacent local agency. Download water agency shape file

Attachment(s):

• WaterDistricts_InVicinity.zip (148.9kB) Uploaded on 03/31/2016 at 07:40AM

6. Any information, if necessary, to enable DWR to satisfy the requirements of a responsible agency pursuant to the California Environmental Quality Act.

This request to modify basin boundaries is exempt from the California Environmental Quality Act (CEQA) because there is no possibility that the adoption of the proposed Jurisdictional Internal modifications to the basin boundary for the purposes of identifying non-adjudicated areas will have a significant effect on the environment, this activity is taken in protection of natural resources, and this activity is taken in protection of the environment. Further, SGMA exempts preparation and adoption of Groundwater Sustainability Plans from CEQA review for the purposes of which this basin boundary modification request is a necessary initial step.

E. General Information

1. Describe the lateral boundaries of the alluvial aquifer or aquifers that form the groundwater basin and the definable bottom of the basin. The description must be in terms that are clear, definite, and sufficiently detailed to allow an authoritative map of the proposed basin boundaries to be plotted using the given description.

For the purposes of SGMA compliance and clear definition of the management area of the non-adjudicated portion, only one section of the larger Riverside-Arlington Subbasin (8-02.03) would be modified in this request. The balance of the basin boundaries would conform to the existing Bulletin 118 defined boundaries. Western is requesting that the Riverside-Arlington subbasin be bisected along the Judgement boundary as defined by the 1969 Western-San Bernardino Judgment. The non-adjudicated/SGMA management area would be the south-west portion.

F. Notice and Consultation

1. List all local agencies and public water systems affected by the basin(s) modification request.

Riverside Public Utilities, Western Municipal Water District

2. Explain the methods used to identify interested local agencies and public water systems in the affected basin(s):

Local agencies were identified in the Arlington Basin Groundwater Management Plan. The Plan was adopted in October 2012 following years of stakeholder workshops and participation. A map showing the water agencies is attached.

Attachment(s):

• Water Agencies.pdf (487.1kB) Uploaded on 03/30/2016 at 09:36AM

3. Provide information regarding the nature of consultations with affected or interested agencies. Attach and cite any copies of correspondences with local agencies and public water systems and/or any other persons or entities consulted.

The only boundary that is being modified from the existing Bulletin 118 boundaries is on the north-east side of the basin which is in the Riverside Public Utilities (RPU) service area. As such, Western reached out to RPU staff via email. A copy of this correspondence is attached.

Attachment(s):

• RPU Email_SGMA - Basin Boundary Modification for Arlington Basin.pdf (1.7MB) Uploaded on 03/30/2016 at 09:47AM

4. Provide a summary of all public meetings at which the proposed boundary modification was discussed or considered by the requesting agency. Attach and cite any copies of agendas and notices published.

On March 2, 2016, during the Staff Reports section (Sec. 6.A.2.c) of the Regular Board Meeting, staff gave a PowerPoint presentation regarding the exploration of a basin boundary adjustment for the Arlington Subbasin to identify the non-adjudicated areas of the larger Riverside-Arlington Basin. The published agenda, meeting minutes, and the PowerPoint have been attached. On March 16, 2016, during the Action Agenda section (Sec. 5.C) of the Regular Board Meeting, the Board of Directors unanimously approved Adoption of Resolution 2937 Requesting a Jurisdictional Boundary Adjustment for the Riverside-Arlington Subbasin to clearly identify the non-adjudicated area of the subbasin. The published agenda, the Board Letter, and a summary of the Board meeting have been attached. As the meeting minutes have not yet been approved by the Board of Directors, the document has not been attached. The March 16, 2016 meeting minutes will be considered by the Board on April 6, 2016.

Attachment(s):

• 03022016 Board Agenda.pdf (112.5kB) Uploaded on 03/30/2016 at 11:39AM
• Board PowerPoint from March 2 2016.pdf (876.5kB) Uploaded on 03/30/2016 at 11:39AM
• 16-03-02 Board Minutes.pdf (221.3kB) Uploaded on 03/30/2016 at 01:20PM
• Board Letter from March 16 2016.pdf (231.8kB) Uploaded on 03/30/2016 at 01:21PM
• 03162016 Board Agenda.pdf (113.3kB) Uploaded on 03/30/2016 at 01:20PM
• 03162016 Board Summary.pdf (464kB) Uploaded on 03/30/2016 at 01:21PM

5. Attach a copy of all comments regarding the proposed boundary modification received by the requesting agency and a summary of any responses made by the requesting agency.

Except the support correspondence with Riverside Public Utilities (attached in F-3 above), no comments have been received.

G. General Existing Groundwater Management

1. Explain how sustainable groundwater management exists or could likely be achieved in the basin:

This boundary modification is to clearly identify the non-adjudicated area of the Riverside-Arlington Basin. The adjudicated area (the Riverside Basin) is currently administered by the Court-appointed Western-San Bernardino Watermaster. A separate report will be filed as required by SGMA. The non-adjudicated area of the Riverside-Arlington Subbasin (the Arlington Basin) is already managed by Western MWD. Western adopted a Groundwater Management Plan in 2012. This Basin Boundary Request is simply to clearly define the non-adjudicated area to be managed under SGMA. Western, with stakeholder collaboration, will modify the existing Plan as necessary to meet the requirements of SGMA.

2. Explain how the proposed boundary modification would affect the ability of adjacent groundwater basins to sustainably manage groundwater in those groundwater basins.

This proposed boundary modification will have no negative impacts on the ability of adjacent groundwater basins to sustainably manage groundwater in those groundwater basins.

3. Provide a historical summary of the sustainable management of groundwater levels in the proposed basin(s) or subbasin(s).

The attached pages are from the 2012 Arlington Basin Groundwater Management Plan and include a map of the wells monitored for water levels and the associated hydrographs.

Attachment(s):

• Water Level Hydrographs_2012 Plan.pdf (863.5kB) Uploaded on 03/30/2016 at 03:08PM

4. Discuss potential impacts to state programs resulting from the proposed boundary modification, including, but not limited to, the California Statewide Groundwater Elevation Monitoring (CASGEM), Groundwater Management Plans developed pursuant to AB 3030, Groundwater Sustainability Plans developed pursuant to the Sustainable Groundwater Management Act, any applicable state or regional board plans, and other water management and land use programs.

Approval of this basin boundary modification is not likely to significantly impact other State programs. Western is already the designated CASGEM monitoring entity for the basin and will continue to report. Western also developed the 2012 Groundwater Management Plan. Western will update the 2012 Plan to ensure complete compliance with SGMA.

H. Local Support

1. Provide any evidence that sufficient information was provided to affected agencies and systems regarding the proposed boundary modification.

This request is for a Jurisdictional internal boundary modification effectively removing a small portion of adjudicated area on one side of the existing Bulletin 118 boundary. This single modification impacts only one of the three local agencies that overlie the basin, Riverside Public Utilities (RPU). Western staff contacted RPU directly. A copy of that email correspondence is attached.

Attachment(s):

• RPU Email_SGMA - Basin Boundary Modification for Arlington Basin.pdf (1.7MB) Uploaded on 03/30/2016 at 03:38PM

2. Provide a list of all affected agencies and affected systems that submitted comments and/or documents in support or opposition to the proposed boundary. The agency submitting their support or opposition for a boundary modification must provide a copy of a resolution formally adopted by the decision-making body of the affected agency or system or a letter signed by an executive officer or other official with appropriate delegated authority who represents the agency or system. Attach copies of the resolution and/or signed letter detailing the support or opposition submitted.

No formally adopted resolutions or letter signed by executive officers in support or opposition have been received by Western.

3. Provide any evidence that rebuts any opposition to the proposed boundary modification.

n/a

I. Hydrogeologic Conceptual Model

1. Principal aquifer units within requested basin.
2. Lateral boundaries of the proposed basin, including:
   1. Geologic features that significantly impede or impact groundwater flow.
   2. Aquifer characteristics that significantly impede or impact groundwater flow.
   3. Significant geologic and hydrologic features and conditions of the principle aquifer units, as appropriate, including information regarding the confined or unconfined nature of the aquifer, facies changes, truncation of units, the presence of faults or folds that impede groundwater flow, or other groundwater flow restricting features.
   4. Key surface water bodies, groundwater divides and significant recharge sources.
3. Recharge and discharge areas within the basin.
4. Definable bottom of the basin or subbasin.

The department may waive this requirement for an internal boundary modification if the requesting agency is able to demonstrate that the proposed boundary modification is unlikely to affect sustainable groundwater management.

This request is for an internal boundary modification that is unlikely to affect sustainable groundwater management. Nonetheless, attached is Section 2 - Hydrogeologic Setting, of Western's Arlington Basin Modeling Report completed in 2008.

Attachment(s):

• ArlingtonModelingReportSection2_Hydrogeologic Setting.pdf (5.1MB) Uploaded on 03/30/2016 at 03:28PM

L. Technical Studies for All Jurisdictional Modifications

1. A water management plan that covers or is in the immediate vicinity of the proposed basin or portion of the proposed basin and satisfies the requirement of Water Code sections 10753.7(a) or 10727 by attaching one of the following:
   1. An adopted groundwater management plan, a basin wide management plan, or other integrated regional water management program or plan.
   2. Management pursuant to an adjudication action.
   3. One or more technical studies that cover the relevant portion of a basin or subbasin and adjacent areas.

URL: http://www.wmwd.com/DocumentCenter/View/1213

2. A statement of the existing and planned coordination of sustainable groundwater management activities and responsibilities where required.

Western is committed to sustainable groundwater management in the Arlington Basin. Chapter 6 of the 2012 Arlington Basin Groundwater Management Plan (URL to the Plan provided in L-1 above) addresses the Plan's elements and actions items to address these elements. Chapter 7 addresses Implementation of the action items. Western operates a groundwater desalter in the basin to remove salts before delivery. The brines are disposed of outside the Basin via the Inland Empire Brine Line operated by SAWPA. Additionally, Western has secured land for future recharge o fthe basin