Storm water project redux or just a coincidence?
APIP 2008 & City of Berkeley Storm Drainage Master Plan 1994

Many of those concerned with the 2008 Aquatic Park Improvement Program (APIP) see it as a stormwater management plan weakly disguised as a habitat restoration plan. When we compare it to the City of Berkeley Storm Drainage Master Plan, presented to the city in July 1994, the parallels become more obvious.

Highlights from the Storm Drainage Master Plan from July 1994

In the map above, the brownish lines represent existing pipes:

• Two large, parallel connectors between Potter and Model Yacht Basin
• Two small pipes from Model Yacht Basin to the Main Lagoon
• One from Model Yacht Basin to the Bay (the bay side of this pipe has not been found, and there is little or now flow through it)
• One from Radio Tower Pond to the Bay (this one is mostly blocked, and is the cause of the lane closure on West Frontage Road)

Potter Creek and the south end

In the Potter Street Overflow Diversion (Project 18) section (page 6-11), the report states: [emphasis added by EGRET]

The lowest point in the Potter System is located in the vicinity of Potter and Bolivar Streets, this location is subject to flooding during high runoff and/or tide conditions. A high flow diversion structure would be constructed at Potter and Bay Streets to hydraulically relieve the portion of the Potter System downstream of this location. The diverted flow would be directed north to the main lagoon of Aquatic Park. Two 6- x 10-foot box culverts would be required to handle the diverted flow. [The "Recommended Hydrologic Alternative" of APIP calls for 30 square feet of opening, about one-quarter of this.]

During smaller storms, runoff would be discharged to the Bay through the existing outfall. The existing diversion in the vicinity of Potter and Bay Streets may be modified in accordance with plans developed in the Aquatic Park Master Plan.

This water project must be coordinated with other City projects, and with findings of the City's Water Quality Management Plan, Emergency Saltwater Fire Protection, and Aquatic Park Master Plan.

Necessity for pumping stations

In the Aquatic Park Pumping Station and Force Main (Project 19) section (page 6-12), the report states: [emphasis added by EGRET]

Preliminary calculations indicate that during the design storm approximately 4,330,000 cubic feet [99.4 acre-feet] of storm water would be discharged into the north end of Aquatic Park from the Addison Street Outfall and approximately 6,440,000 cubic feet [148 acre-feet] would be discharged into the south end of Aquatic Park from the Potter Street Overflow Diversion and Heinz Street overflow. This storm water would raise the water level in Aquatic Park by approximately 7.4 feet, assuming no outfall to the Bay. This level of water would flood the area adjacent to the park, including existing buildings along Bolivar Drive.

In the map above, the brownish line represents the connector between the Strawberry Creek culvert and the north end of the Main Lagoon.
Underground locations are approximate.

To prevent this flooding, a 150-mgd (225 cfs) pumping station would be required to pump water from Aquatic Park to the Bay during larger storm events, as shown in Figure 6-2. This station would be located at the northern end of the park and would discharge through two parallel 48-inch force mains that would parallel the existing University Avenue outfall. Consideration should be given to combining this station with the proposed Auxiliary Fire System pumping station to be located in the same area. Gravity flow from the park was considered but would not be feasible because of the small head [pressure] difference between Aquatic Park and the Bay.