Modified Firm Storage Rights - Effective April 1, 2020

Date: March 12, 2020

The 2019 Gas Transmission and Storage (GT&S) Rate Case Final Decision (D.) 19-09-025, issued on September 23, 2019, adopted the Natural Gas Storage Strategy (NGSS) that substantially change PG&E’s gas storage asset holdings and CGT’s role in the market and operational functions. The NGSS balances PG&E’s system reliability and increased gas storage costs due to new storage maintenance regulations. In addition, as of part of the NGSS, the Commission adopted PG&E’s proposal to decommission the Los Medanos and Pleasant Creek fields. On January 31, 2020, PG&E filed with CPUC a plan to market the assets for sale. However, the sale of Los Medanos will not proceed until after PG&E files with the CPUC in 2022 showing McDonald Island will have adequate capacity to meet the reliability needs of the system.


Effective April 1, 2020, the PG&E firm storage services are shown in the table below:


Storage ServicesInjection (mmcf/d)Inventory (bcf)Withdrawal (mmcf/d)
Core Firm Service214243251210*307
Inventory Management (Balancing)752004575300
Reserve Capacity (New)025010250



*PG&E Storage Withdrawal – January 15


Modified Balancing Services and Impacts on OFOs


Effective April 1, 2020, there will be a change in the way PG&E determines if an OFO is needed.


  • Prior to April 1, 2020, pipeline balancing services are provided on California Gas Transmission's system by an allocated 4.040 Bcf of storage inventory, 75 MMcf/d of injection capacity, and 75 MMcf/d of withdrawal capacity. Currently (Pre-NGSS), PG&E utilizes the 75 MMcf/d of injection and withdrawal in the next-day daily plans for determining end-of-day inventory forecast and OFOs.
  • Beginning April 1, 2020, pipeline balancing services will increase to an allocated 5 Bcf of storage inventory, 200 MMcf/d of injection capacity, and 300 MMcf/d of withdrawal capacity. However, PG&E will only plan to use the balancing resources during the intraday to manage the end-of day pipeline inventory.
  • No changes to the balancing rules for daily and monthly imbalances.
  • PG&E will establish a new Reserve Capacity to provide reliability against a loss of supply of up to 250 mmscf/d that will be used to resolve significant, unplanned equipment outages, among other supply problems. The Reserve Capacity service is an allocated 1.0 Bcf of storage inventory, 25 MMcf/d of injection capacity, and 250 MMcf/d of withdrawal capacity


Customers should continue to monitor Pipe Ranger Recent NewsSystem Inventory Status and the Storage Activity Forecast for up-to-date information on pipeline balancing services. The current inventory of Imbalance Gas in Storage can be found on the Pipe Ranger Operations page.


If you have any questions, please call Allen DeBrum at 925.244.3498.