Thursday, August 24, 2017

Baltimore water: A tangled web and smaller lakes

In 1920 Baltimore was a shining beacon of progressive public works and Baltimore local water engineer and Hopkins professor Abel Wolman a hero. His Baltimore water system lived even longer than he (Wolman died in 1989 at the age of 96) but decay and new rules have forced a multi billion dollar overhaul of Baltimore's water and sewer infrastructure including several open reservoirs located inside the city limits.
Visualization of a possible bandstand at Druid Lake (GWWO Architects)

Water has been a municipal affair since 1854 when the City of Baltimore bought the private Baltimore Water Works which had incorporated in 1808. Slowly but surely water supply from fountains and wells was changed to include water from the Jones Falls and storage and pumping stations were added. Lake Montebello and the 55 acre Druid Lake (then called Lake Chapman) were completed in 1881 and in 1871 respectively. Eventually Lake Ashburton was added and all lakes connected with pumping stations. The matter was further complicated after an additional water supply was created tapping into the Susquehannah during extreme drought conditions. All in all the current water service area encompasses some 560 square miles and serves 1.8 million people via 4,500 miles of pipe.
Under normal operating conditions, water flows by gravity from the Loch Raven Reservoir to the Montebello Filtration Plants through the Gunpowder falls-Montebello tunnel, a concrete lined tunnel, 12 fee in diameter, and approximately seven miles in length, this tunnel was constructed through solid rock.
14 acres less lake: Submerged tanks at the historic Druid Lake Park (DPW)
When the water level of the dam is lowered a few feet below the crest of the dam, the discharge valves at Prettyboy Dam are opened. The water released flows down the bed of the gunpowder Falls into Loch Raven Reservoir, thus maintaining the water level in the latter reservoir at a predetermined elevation. If the level in the Loch Raven Reservoir drops too low for gravity flow, water can be pumped from the Loch Raven reservoir ti the Montebello Filtration Plants by a pumping station located at the plants. The station, called the Montebello Raw Water Distribution Center, was constructed in 1958 in conjunction with the Susquehanna Water Supply Project. The station contains three pumps, each having a capacity of 120 million gallons per day, and appurtenant equipment.
Water from Liberty Reservoir flows through a concrete lined tunnel, 10 feet in diameter, to the Ashburton filtration Plant, a distance of approximately 12.5 miles. This tunnel was constructed through solid rock.
Since the service system is truly regional, it is since 1979 partly managed by a regional Reservoir Watershed Agreement that was renewed on 1984 and again in 2005 under the oversight  of a Watershed Protection Committee at the Baltimore Metropolitan Council. Watershed and drinking water sources are one thing, stroage tanks and treatment plants are another.
Rendering of completed project (DPW)

While the downtown sinkholes from sewer main failures and the water main breaks causing fountains and flooding have received widespread media coverage,  the much more visible aspect of Baltimore's open reservoir lakes largely flowed under the radar, stirring little interest except for the immediately surrounding communities.

The beauty of man-made lakes enhanced city neighborhoods and reliably provided healthy drinking water for over 100 years, especially since Wolman had introduced chlorination of drinking water and vastly reduced the risk of contamination. But no longer,  in 2006, bureaucrats concerned in equal parts about clean water and homeland security offered the nation with the not very beautiful acronym monster,  LTE2SWTR, which stands for Long Term 2 Enhanced Surface Water Treatment Rule.
A historic image of the current lake's western edge (Kilduff)

True to its forward looking history, DPW became active well before the new regulations went into effect and commissioned a study with Baltimore's engineering firm RKK which was published in 2004.  For a time it was seriously feared that the terrible name would require equally terrible actions, such as giant covers over the lakes. But by 2013 Baltimore's Department of Public Works (DPW) had developed better ideas and in June 2014 DPW and the Department of Recreation and Parks (DRP) signed an agreement about two underground storage tanks in Druid Lake.

The underground storage tanks submerged in the lakes sounds a lot smarter than covering the lakes, above ground storage or additional treatment of water gained from open surfaces. However, in detail, the tank solution isn't quite as innocent as residents around Druid Lake and the Friends of Druid Lake Park have found out over the years when actual plans were presented. In the version that is currently under construction, two combined 54 million gallon water tanks will be buried at the western end of the lake and actually reduce the lake by at least 6.3 acres (earlier presentations noted 14 acres). DPW touts this as new acres of park that will include a welcome center. "When finished, the New Druid Lake will be better than ever, with increased public amenities and more open green space", DPW's press release states. But funding for amenities is just as murky as the future of the reduced now merely decorative lake itself which would need measures to keep the water fresh that haven't been figured out in full. The Druid Lake project alone is projected to cost $164.1 million and is supposed to be complete in the spring of 2022.
Proposed tank locations for Ashburton Lake (AECOM)

There is no word about funding in the DRP/DPW agreement, but from what the Board of Public Works approved it is understood that DPW will pay for widening the path on the southern part of the lake and constructing the base for a band shell. The Baltimore City Department of Recreation and Parks is expected to find funding to complete the band shell and related park improvements. A video of a GWWO designed bandshell can be seen here.

Construction is complete at Lake Montebello and underway underway at the $75 million Guilford Reservoir project on West Cold Spring Lane where also two large storage tanks are submerged within the footprint of the current lake. Per DPW there are four phases of the project a bypass of the 48 inch water main is complete and work on the reservoir itself, including draining it and installing tanks is underway and will be completed by August 2018. The construction of a pump station and the activation of the tanks will follow in June 2018 and be completed in June 2019 with  site restoration and landscaping planned for June to November 2019. The last in the trio of reservoir-lake projects in the City will be the $120-140 million Ashburton Lake tanks. There a 2013 study shows the tanks to be submerged under Hanlon Park. A status report about compliance with the federal rule can be found here.
Design concept for an overlook option at Ashburton Lake (DPW)

Residents of Baltimore City and County already feel the pinch of DPW's large construction portfolio intended to upgrade the water and sewer for the future, in their water bills.

One has to wonder whether LTE2SWTR really brings better or safer water to the region. One can think of much else in Baltimore's water and sewer system that would need upgrades and would result in a measurable difference in water quality, namely the decrepit state of all the mains. The state of supply lines to many Baltimore schools is so poor, that drinking fountains have been shut off because of lead contamination. Instead, three of Baltimore's neighborhood assets, beautiful lakes, will be construction sites for years to come.

Klaus Philipsen, FAIA

Druid Lake project (DPW)

Friends of Druid Hill Park

Come out to celebrate the Baltimore region’s drinking water reservoirs! The celebration will be Saturday, Aug 26, from 9 a.m. to 3 p.m. This event takes place at the Cromwell Valley Park (Willow Grove Nature Center) 2175 Cromwell Bridge Road. 

Dam Jam is presented by the Baltimore City Department of Public Works (DPW), in partnership with Baltimore County and the Hamilton Art Collective.

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