To: Members of the Castle Rock Water Commission
From: Mark Marlowe, P.E., Director of Castle Rock Water
Lauren Moore, Water Resources Manager
Adriana Alfaro, Water Resources Program Analyst
Title
Update: Water Court Cases [Cases located in Douglas County, Weld County and other areas near the Lower South Platte River)
Town Council Agenda Date: October 20, 2026
Body
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Executive Summary
The acquiring, changing, using and protecting of the Town’s water rights is a key component of the Town’s long-term renewable water plan as well as an important aspect of managing our groundwater rights. This requires the Town to file applications in Water Court and file oppositions where an application by another entity has the potential to injure the Town’s water rights. The Town is continuing to contract with Lyons Gaddis as our water attorneys and W.W. Wheeler Associates for water resources consulting support. The purpose of this memorandum is to update Town Council on the Town’s current Water Court cases.
The Town currently has six active cases where we are the applicant and three pending cases where we will be the applicant. One of the cases is related to Castle Rock’s future water rights along the lower South Platte River at Fremont Butte Reservoir. Castle Rock is partnering with Parker Water & Sanitation District and Lower South Platte Water Conservancy District on the Platte Valley Water Partnership (PVWP) Project. Four of the applications are for reasonable diligence related to Plum Creek water rights and Roth-Sublette Recharge Project. One case is for an application for an augmentation plan on Plum Creek, which would replace Town’s out-of-priority diversions on East Plum Creek and Plum Creek. There are sixteen cases that the Town is or was opposing that could have a negative impact (i.e. injure) our water rights. These cases are summarized in Attachment A with additional details in the following discussion.
To date in 2026, Castle Rock Water (CRW) has spent $716,586 of our budgeted $653,008 on costs related to water court cases. A budget transfer in the amount of $275,000 will be completed to account for additional legal costs to date and through the end of the year. The lions share of the costs have been associated with CRW’s work obtaining a water right for the Platte Valley Water Partnership project. This work was successful, and on 10/2/2026, CRW received that water right in huge victory for long-term water supply planning for the Town. This storage water right provides a maximum annual diversion of 16,037 AF in the Fremont Butte Reservoir and forebays on the South Platte River near Fort Morgan.
Discussion
The Town has six active and three pending Water Court Cases in which the Town is the applicant. These cases are summarized below:
1. 21CW3185 - This case was filed on October 25, 2021. This is an application for a conditional storage right on the South Platte River at (a future) Fremont Butte Reservoir. The case has been settled and CRW has secured the water right. The Town’s case was consolidated with Parker and Lower South Platte’s Case No. 19CW3253. This is a project with Parker Water and Sanitation District (PWSD) that would divert water from the lower South Platte River and pipe it south and west to Rueter-Hess Reservoir for delivery to Parker and the Town. The final decree was issued 10/2/2026.
To date in 2026, the Town has spent $325,016 on this case between legal and water resources consulting fees. Approximately $885,000 has been spent over the life of this case between legal and water resource consulting fees.
2. 25CW3133 - Application for diligence 17CW3211 and to make conditional water rights partially absolute for Plum Creek Diversion, Castle Rock Reservoir Nos. 1 and 2, and exchanges. The case is before the Water Referee and has one opposer with zero stipulating.
To date in 2026, the Town has spent $5,316 on this case between legal and water resources consulting fees.
3. 26CW3026 - Application for plan for augmentation on Plum Creek. Currently before the Water Referee with thirteen opposers and zero stipulating. The status conference is scheduled for 1/27/27.
To date in 2026, the Town has spent $28,681 on this case between legal and water resources consulting fees.
4. 26CW3098 - Application for diligence 86CW378/86CW379 (East Plum Creek and Exchanges). This case is currently before the Water Referee with zero opposers.
To date in 2026, the Town has spent $4,518 on this case between legal and water resources consulting fees.
5. 26CW3146 - Application for diligence 89CW212 for exchange (East Plum Creek). This case is currently before the Water Referee and statements of opposition are due 11/30/26.
To date in 2026, the Town has spent $3,830 on this case between legal and water resources consulting fees.
6. 26CW3037- Application for diligence 89CW27 for Roth-Sublette Recharge Project. This case is currently before the Water Referee. One opposer is the Lower Latham Reservoir Company. A status conference was held on 9/29/26.
To date in 2026, the Town has spent $917 on this case between legal and water resources consulting fees.
7. 27CW____ - Pending application for quantification of East Plum Creek lawn irrigation return flows (LIRFs). Goal is to file application by 12/31/2026.
To date in 2026, the Town has spent $2,132 on this case between legal and water resources consulting fees.
8. 27CW____ - Pending application for quantification of Cherry Creek LIRFs. Goal is to file application by 3/31/27.
To date in 2026, the Town has spent $0 on this case between legal and water resources consulting fees.
9. 27CW____ - Pending application for diligence 05CW270 for Ravenna Pipeline. Diligence application due 12/31/2027.
To date in 2026, the Town has spent $0 on this case between legal and water resources consulting fees.
The Town has sixteen current active cases where the Town is an opposer.
Costs for opposition to date in 2026 have been $235,329. Costs are typically on the order of $93,000 annually. A heavier load of cases came forward this year, however.
These cases are summarized below:
1. 19CW3253 - The Town was an opposer in the PWSD and Lower South Platte Water Conservancy District’s (LSP) storage rights, appropriative rights of exchange and change of water rights on the South Platte near Box Elder Creek during 2024. The Town was opposing this case because it may have caused injury to Town’s water rights on the South Platte River and Box Elder Creek. The Town is now a partner with PWSD and LSP. The Town has stipulated. Final decree was issued 10/2/2026.
To date in 2026, the Town has spent $0 as an opposer on this case.
2. 20CW3215 - The Town is currently an opposer in the BennT Creek Regional Water Authority and SP Water Company application for storage rights on South Platte River. The case is currently before a Water Judge, and the Town has stipulated. The Town was opposing this case because it may cause injury to Town’s water rights on South Platte.
To date in 2026, the Town has spent $32,649 on this case.
3. 21CW3193 - The Town was currently an opposer in the Central Colorado Water Conservancy District application for appropriative rights of exchange and approval of augmentation plan including exchanges. The case is currently before the Water Judge, and the Town has stipulated. The Town was opposing this case due to potential injury to Town’s water rights on Box Elder Creek.
To date in 2026, the Town has spent $0 on this case.
4. 23CW3129 - The Town is currently an opposer to the Mountain Plains Investment Corporation application for change of water rights and addition of replacement water to the existing plan for augmentation on Cherry Creek. The case went before the Water Judge, and a motion for final ruling was filed 9/25/2026. The Town was successful and the case was resolved in the Town’s favor. The Town was opposing this case due to potential injury to Town’s water rights on Cherry Creek.
To date in 2026, the Town spent $175,864 on this case. Town is seeking reimbursement of costs from Mountain Plains Investment Corporation and expects to be awarded some of those costs (estimate of $33,000).
5. 23CW3180 - The Town is currently an opposer to the Central Colorado Water Conservancy District application for change of water rights to include alternate places of storage and alternate points of diversion. This case is currently before the Water Judge and the status conference scheduled for 12/15/2026. The Town is opposing this case due to potential injury to the Town’s water rights in Chatfield Reservoir and Rueter-Hess Reservoir. The Town is trying to work with Central Colorado Water Conservancy District to partner on this water right.
To date in 2026, the Town has spent $543 on this case.
6. 24CW3088 - The Town is currently an opposer to the Central Colorado Water Conservancy District application to make conditional water rights partially absolute and for finding a reasonable diligence. The case was re-referred to the Water Judge. The Town is opposing this case due to potential injury to the Town’s water rights in Chatfield Reservoir.
To date in 2026, the Town has spent $931 on this case.
7. 24CW3164 - The Town is currently an opposer to the Equus Farms, Inc. application for water rights and approval of plan of augmentation on South Platte River. The case is before the Water Referee. The status conference is scheduled for 12/16/2026. The Town is opposing this case due to potential injury to the Town’s water rights on Box Elder Creek and the South Platte River.
To date in 2026, the Town has spent $4,921 on this case.
8. 25CW3046 - The Town is currently an opposer to the Central Colorado Water Conservancy District application to make conditional water rights partially absolute and for finding of reasonable diligence on Plum Creek and the South Platte River. The case is before the Water Referee. The Town has stipulated. The Town was opposing this case due to potential injury to the Town’s storage rights in Chatfield Reservoir.
To date in 2026, the Town has spent $81 on this case.
9. 25CW3062 - The Town is currently an opposer to the Riverside Irrigation Company, Riverside Reservoir and Land Company, and East Cherry Creek Valley (ECCV) application for alternate point of diversion. The case is before the Water Referee. The Town has stipulated. The Town was opposing this case due to potential injury to the Town’s water rights in South Platte River.
To date in 2026, the Town has spent $1,608 on this case.
10. 25CW3177 - The Town is currently an opposer to Colorado Water Conservation Board, Public Service Company of Colorado, and Colorado River Water Conservancy District application for change of water rights. The case is before the Water Referee with the trial scheduled for 7/10/2028. The Town is opposing this case in partnership with Aurora Water to protect the Town’s interest in the Water Infrastructure Supply Efficiency (WISE) Partnership Second Amended and Restated Water Delivery Agreement.
To date in 2026, the Town has spent $9,568 on this case.
11. 25CW3195 - The Town is currently an opposer to Dominion Water and Sanitation District application for direct flow and storage rights on Plum Creek and its tributaries and approval of plan for augmentation. The case is before the Water Referee. The Town was opposing this case due to potential injury to the Town’s water rights decreed to divert from East Plum Creek, Plum Creek, and South Platte River.
To date in 2026, the Town has spent $3,673 on this case.
12. 26CW04 - The Town is currently an opposer to the Assemany et al complaint for Declaratory Relief and Correction of Records. The case is before the Water Referee with a motion to consolidate multi-district litigation pending. The Town was opposing this case to protect the Town’s Denver Basin Groundwater adjudications.
To date in 2026, the Town has spent $1,128 on this case.
13. 26CW3040 - The Town is currently an opposer to the Greatrock North Water and Sanitation District application for approval for augmentation and change of water rights in Adams County. The case is before the Water Referee with a status conference scheduled for 10/27/26. The Town is opposing this case due to potential injury to the Town’s water rights in Box Elder Creek.
To date in 2026, the Town has spent $1,164 on this case.
14. 26CW3023 - The Town is currently an opposer to the State Engineer and Director of Colorado Division of Water Resources application for review of a substitute water supply plan for a decreed agricultural water protection water right. The case is before the Water Referee. The Town is opposing this case to protect the Town’s augmentation plans and changes of water rights.
To date in 2026, the Town has spent $1,296 on this case.
15. 26GW01 - The Town is currently an opposer to the Rodeo Dunes Water, LLC, Wisconsin Dunes, LLC, and Leopold Real Estates, LLC application for change of type of use and place of use of a well permit in the Lost Creek Designated Groundwater Basin. The case is before the Groundwater Commission. The Town is opposing this case due to potential injury to the Town’s water rights in Lost Creek.
To date in 2026, the Town has spent $2,439 on this case.
16. 26GW10 - The Town is currently an opposer to the LC Holding LLC application for change of type of use and place of use of a well permit in the Lost Creek Designated Groundwater Basin. The case is before the Groundwater Commission. The Town is opposing this case due to potential injury to the Town’s water rights in Lost Creek.
To date in 2026, the Town has spent $0 on this case.
Budget Impact
In the annual budgeting process, Castle Rock Water budgets money for Legal Services related to Water Court cases, other water resource legal matters, and Intergovernmental Agreement negotiations. Castle Rock Water also budgets money for water resources consulting services related to Water Court cases and the Town’s water rights, water resources planning and evaluation, preparation of technical memos and engineering reports, water rights accounting, and other as-directed matters.
To date in 2026, Castle Rock Water has spent $716,586 of our budgeted $653,008 on costs related to water court. Legal services costs for the Town to date have been $601,862 while engineering services have cost $141,724. To account for legal costs through the end of the year, a budget transfer of $275,000 will be completed from 211-4340-443.3070 (Professional Services) to 211-4340-443.30-50 (Legal Services).
Staff Recommendation
Staff recommends continuing to file and work water court cases as the applicant, which will provide maximum benefit for use of our water rights, and file cases as an opposer where our water rights could be impacted. Where we are the applicant, the goal is to obtain stipulations from opposers as quickly as possible while being protective of the Town’s water rights. On cases we oppose, we want to stipulate as early as possible, but we must make sure we can do this while protecting our rights. Staff will continue to keep Council updated regarding active Water Court cases on an annual basis.
Attachments
Attachment A: Summary of Cases