NVWS-REPLENISH-001 — Site-specific additional hydrological replenishment

DRAFT FOR CONSULTATION. NVWS v0.1 (October 2026). This is a proposed Nexus Water DAO LLC standard. It is not approved, adopted or independently assured. The methods have not been approved by an independent technical council. No Verified Water Credits (VWC) have been issued, and none are offered for sale. References to WRI, AWS, Gold Standard, ISO, EPA, FTC, SEC, CFTC or any other organization are not endorsements. Comments: josh@nexuswater.xyz

Version 0.1 · 2026-10-03 · Nexus Water DAO LLC

Status: proposed Nexus policy / technical draft. Not an approved or independently assured credit standard.

Required methodology specification

Field	Proposed requirement
1. Methodology ID	NVWS-REPLENISH-001
2. Version	0.1-draft; proposed, not approved
3. Effective date	None for live issuance; draft baseline 2026-10-03
4. Eligible activities	Managed aquifer recharge or other site-specific intervention with a validated hydrological model. Restoration, forests, soil practices and wetlands require activity-specific annexes; this umbrella draft does not approve a universal formula.
5. Geographic applicability	Pilot-specific only after local permit, source-catchment and technical applicability review; no blanket global approval.
6. Environmental objective	VWC-REPLENISH; method-specific additional recharge / instream availability; never a universal catch-all metric
7. Project boundary	Connected source, vadose zone/aquifer or stream reaches, extraction points, travel time, storage, competing users, evapotranspiration and downstream flows.
8. Water source	Identify official hydrogeological/catchment units and demonstrated hydraulic connectivity. Document permits, water quality, land/water rights and destination of retained water.
9. Baseline rules	Calibrated without-project counterfactual accounting for rainfall, recharge, runoff, evapotranspiration, abstraction and background conditions. Use controls/model validation suitable for local hydrology. Document uncertainty and time lag before choosing a crediting period.
10. Additionality rules	Apply the NVWS additionality policy (draft, publication pending); environmental counterfactual, regulatory and temporal tests required; method/project annex specifies practice and finance tests with evidence and rationale.
11. Monitoring	Inflow/outflow, precipitation, soil/storage changes, infiltration where relevant, groundwater levels/quality, evapotranspiration model inputs, extraction and receptor response. Flow into a basin alone is insufficient.
12. Devices	Calibrated, appropriately sized/installed meters with serial, unit, accuracy specification, commissioning and calibration history. Approved engineering models where the project annex permits; no brand endorsement implied.
13. Equations	Conceptual only: G_t = max(0, H_project,t − H_baseline,t), where H is the specific validated beneficial hydrological outcome in m³ at the eligible receptor and time. E_t = max(0, G_t − U_t − L_t) × A_t. Each project annex must define and validate H; this draft intentionally provides no executable default recharge estimator.
14. Uncertainty	Project annex defines uncertainty budget, missing-data rule, correlation/error propagation and chosen conservative deduction. No default confidence factor from evidence tier. Technical reviewer must approve parameters before real issuance.
15. Leakage / adverse effects	Infiltration ≠ recharge ≠ available beneficial water. Exclude water that would have arrived anyway, evapotranspiration loss, displaced downstream benefits, induced abstraction and counted storage that is later released within the same accounting period. Model return/withdrawal timing and persistent versus annual benefit explicitly.
16. Allocation	Explicit rights and pool-level allocation ≤100%; apply only once after conservative physical quantity. Coordinate utility and sponsor shares.
17. Data quality	Immutable originals, aligned periods, explicit units/read types, calibrated instruments, anomaly resolution and source reconciliation; no unresolved material gaps.
18. Verification	Independent qualified verifier and separate registry review; bind decision to exact baseline, calculation and evidence versions.
19. Issuance schedule	Ex-post only, on complete approved monitoring intervals. One annual vintage is preferred where seasonal comparability requires it; no automatic annualization from a short sample.
20. Crediting period	Project-specific, with annual eligibility/maintenance review. No guarantee of future issuance. Material baseline/operating change triggers revalidation.
21. Reversal/correction	Later equipment failure stops future crediting; it does not automatically negate a valid past measured reduction. If prior data or hydrological conclusions were wrong, investigate, cancel active units and invalidate retired claims with append-only history. Stored or time-dependent benefit annexes must define actual reversal obligations.
22. Reporting	Publish redacted PDD, method/version, boundary, metric, vintage, calculation, uncertainty, allocation, verifier opinion, serial batch and separately disclosed co-benefits.
23. Claim language	The exact receptor-specific hydrological outcome defined in the approved annex, with timing and uncertainty; not permanent conservation by default.
24. Exclusions	Rainfall captured credited directly, universal infiltration multiplier, unverified aquifer connectivity, inadequate groundwater-quality safeguards, forecasts credited as ex-post outcome.
25. Double counting	Use the same physical outcome pool across overlapping methods; detect overlapping dates, evidence/meters and external claims. Apply the NVWS double-counting policy (draft, publication pending).
26. Update history	2026-10-03: first technical draft based on user brief; no technical council approval, field validation or public consultation completed.

Worked example

HYPOTHETICAL EXAMPLE for arithmetic only: validated incremental eligible receptor availability 12,000 m³; uncertainty 1,500; adverse-effect deduction 500; allocated share 80% → 8,000 m³. No field inference or accepted coefficient is established by these numbers.

Approval blockers

Live issuance is disabled until a competent reviewer approves the specific baseline, boundary, uncertainty treatment, data-completeness criteria, measurement specifications, rights, safeguards and legal applicability. Publish technical consultation and council disposition. Examples and software calculations are not field validation. The REPLENISH methodology additionally requires an executable, independently reviewed site-specific hydrological annex.

Technical reference use

Use WRI VWBA 2.0 and applicable source-specific engineering as accounting references, not as certification of this formula. Consider AWS site/catchment context, EPA WaterSense specifications for applicable SAVE products, WQBA for quality effects and GHG Protocol for separately quantified carbon co-benefits. See the Nexus reference library (publication pending).