Opflow India

Control Filter Rates Without Rate Controllers

During the filtration cycle (service cycle) the water’s initial operating level is low (height of outlet weir crest + initial head loss). As the media starts clogging, the water head above the media starts increasing gradually. Normally, the water level in the bed reaches up to the crest of the influent splitting weir, the service cycle is completed, and the filter is taken out of service for a backwash. ...Read More

Many Small Water Supply Schemes Need Greater Support

All these issues, and many more minor but relevant ones, make it difficult to provide the masses with safe, potable water. The Maharashtra government’s decision to decentralize its water supply schemes is logical and relevant in many cases. However, considering the ground reality of many rural areas, small capacity schemes need some kind of state assistance, aid, or subsidy in the immediate future if they’re to be sustainable and viable ...Read More

ACE18 Highlights Innovative Water Practice

With the 2015 launch of its India community, AWWAIndia, AWWA is using its knowledge and experience to help the Indian water industry maximize its resources and effectively distribute clean water throughout the country. To help get ACE18 under way, AWWAIndia’s Strategic Board Chair Shirish Kardile and Manager Aninda Sen assisted in the ceremonial lighting of the diya lamp of knowledge during the opening general session ...Read More

Consider the Pros and Cons of Slow Mixing

Hydraulic flocculation is another common approach in which baffled chambers provide turbulence to the water flowing over and under the baffles. “Around-the-corner” baffles are also used. Velocity gradients are generated when a change in flow direction
occurs. The energy input is in the form of head required to pass the flow through the baffles. In the old days, wooden partitions were used as baffles. More recently, brick, concrete, and plastic sheets have been used ...Read More

Installing the First Trilateral Underdrain System in India

The suggested filter underdrain included nozzles on a false-bottom floor for a uniform, concurrent air-water wash—a basic requirement for cleaning these types of beds. The process involves constructing a concrete slab about 0.90 m (3 ft) above the filter bottom to create a plenum chamber. The false slab is supported by multiple stub columns. The nozzles are embedded in the false bottom, over which the media is laid with minimum gravel support. This arrangement is cumbersome to construct and execute, and the additional concrete structural cost is considerable ...Read More

Weirs and Notches Are Honest Friends

Normally,
clarifier launders fall into this class. A peripheral launder is required to collect the clarified water uniformly to ensure equal surface and weir loading. It’s difficult to ensure an equal weir level in concrete over the unit’s entire periphery. In such cases, V-notch weir plates (metallic or plastic) are fixed over the entire weir crest. It’s easy to install and ensure a desired water level ...Read More

An Alert Operator Saves the Day!

At 9:10 a.m., the team leader became slightly anxious, as the residual chlorine still wasn’t reporting nil. He went to the SMBS tanks and checked the solution level and dosing pump. Soon the anxiety started showing on the commissioning team’s faces. The crowd was waiting in anticipation, and the pressure became palpable by 9:20 ...Read More

AICE ’17 to Promote India’s Sustainable Water Future

The time has come to think holistically about all these water-related concerns. Surface water, groundwater, seawater, irrigation water, wastewater, storm water, recycled water, industrial process water, and effluents are all interrelated. AWWA has come up with a practical term for this concept: total water solutions. ...Read More

Inspire India’s Children to Ensure a Sustainable Water Future

To crack the jigsaw puzzle of India’s total water solutions will require many and mighty efforts, but there is hope. Indeed, if the world’s mightiest democracy could do it in the past, why not the largest in the present! ...Read More

Remembering a Failed Clarifier With No Remedy in Sight

I investigated the plant, and everything looked normal on the outside. The clarifier was huge, with a 60-m (54.8-yd) diameter. However, a closer look at the clariflocculator revealed that the vertical hangers at the bottom of the scraper and supported from the rotating bridge were twisted. ...Read More

How Indian Railways Saved a Parched Latur District

Tankers, with a capacity of 20,000 liters each, transported the water to a nearly discarded WTP about 4 km away. Emergency modifications were done to the conventional plant; basically, sodium hypochlorite (bleaching powder) was administered to disinfect the water. Local administrators made this decision to help ensure the water was safe to drink. Another tanker filling station was erected at the Latur WTP to supply the water to various areas in the town. Although the town had a distribution system, the system leaked heavily. ...Read More

What They Don’t Teach You in Engineering School

About 25 years ago, a young civil designer received an urgent telegram, asking him to report to Karmala, a town in Solapur District, Maharashtra, because a new 5-mld water treatment plant was experiencing problems during commissioning. While visiting the site, he found the inlet units (cascade aerator, Parshall flume, and flash mixer) were flooded, and raw water was overflowing the walls. Only a small portion of the water was getting through to the clariflocculator and falling into a peripheral channel. ...Read More

Water Temperature Changes Can Create Clarifier Problems

However, the clarified water quality deteriorated daily between 1100 and 1700 because the sun heated the raw water in the shallow storage lagoons and the exposed pumping main. The temperature increase each afternoon disturbed the plant’s delicate physiochemical balance, as the site’s summer ambient temperature rose to 38°C–42°C during the daytime ...Read More

Save Energy by Refurbishing and Coating Pumps

The study showed that however much a pump’s performance falls below its original manufacturer’s performance curve (head, flow, and efficiency), on average, mechanical restoration only restored approximately 50 percent of a pump’s performance. Sandblasting and coating were necessary to restore the remaining 50 percent ...Read More

Water Treatment Plants Overcome Nature’s Unexpected Behavior

ormally a dam stores heavy silt and acts as a kind of settling basin. However, the reverse was happening at Hatnur. An investigation at the Varangaon intake site revealed that the dam authorities opened the sluices at the bottom of the wall during a monsoon.The heavily silted water found a natural path through the river and intake, causing turbidity to exceed 5,000 mg/L. ...Read More

For Want of a Nail, Poor Water Quality Plagued a Small City

Fresh bleaching powder with an available chlorine content of about 20 percent was procured at the plant. Because the raw water quality had improved considerably then, only a 0.5 mg/L powder dose was given for prechlorination. The pH of the raw water remained about the same. ...Read More

Sustainable Water Treatment Plants Offer Hope for India’s Residents

Raw water is pumped from a canal, located 15 km away, running from the Gangapur Dam. A new 12-mld water treatment plant was constructed, as the old plant had become defunct. The new plant consists of a cascade aerator, Parshall, flume, flash mixer, clariflocculator, three rapid sand filter beds, chemical house, pure water sump and pump house, chlorine room, and tonner platform. ...Read More

Ash Bund Seepage Water Makes Water Treatment Plant Redundant

To improve the area’s drinking water, a small drinking water supply scheme was commissioned about three years ago in a nearby village a couple of kilometers from the south side of the thermal plant. A carbon steel plant is now in place and using about half a million L/day from the Darna. The intake well is 3–4 km away on the village’s south side. ...Read More

Town Faces Double Trouble Because of Failed Drainage

The council officers had accepted this reality. The district’s public health laboratory routinely tested the plant’s water, confirming it as “potable.” ...Read More

Town’s Guardian Angel of Public Health

He quickly went downstairs and opened one of the drain valves to release excess incoming raw water to reduce the overload. Smiling, he told me the problem will soon be over, as it was nearly the end of September. Then there won’t be a problem for another seven to eight months. ...Read More

Let Me Introduce You to a Water ATM

I wondered how the marketing companies had made “RO” a “brand” and not a “process.” So complete is their advertising and selling strategies that villagers have started thinking that “RO ATM” is the safest drinking water available. ...Read More

No Operator, No Water

The plant used some of the simplest, most foolproof technologies available for a manually operated, compact system. Unfortunately, the operator was nowhere to be seen. ...Read More

Namami Ganga Projects Launched in Large-Scale Cleanup Initiative

In a major development on July 7, 2016, the minister of Water Resources, River Development, and Ganga Rejuvenation, Sushri Uma Bharti, announced the launch of 231 projects worth `1,500 crore at multiple locations in Uttarakhand, Uttar Pradesh, Bihar, Jharkhand, West Bengal, Haryana, and Delhi states ...Read More

Report Delves Into Indian State and Local Reforms Needed for Smart City Development

"While cities in India plan to embed technology in the delivery of urban infrastructure and services, they should also plan to bridge the demand-supply gap in the provision of core urban services such as water, waste management, and sanitation," said the forum’s Alice Charles ...Read More