LYNN – The top Water and Sewer Commission salary has increased from $131,300 to $144,500 since 2002 but the number of employees earning over $100,000 stayed level at four until this year.Wastewater treatment director Robert Tina’s salary climbed from $97,878 to $104,648 between 2006 and 2007. Like other top commission officials, Tina works under an employment contract negotiated by the five commissioners.Executive Director Daniel O’Neill is the top paid commission employee earning $144,513.17 in 2007, up from $142,822 in 2006, according to commission earnings records.Director of management operations Robert Tucker’s salary stayed level at $126,938, making him the second highest-paid commission worker while Treasurer David Travers and Chief Engineer Anthony Marino both saw increases in their $100,000-plus pay.Click here for a complete list of Water and Sewer salariesIn 2002, former executive director Stephen Smith earned $131,331 and O’Neill, Travers and Tucker each earned more than $100,000.The commissioners gave O’Neill and other top Water and Sewer earners five-year contracts last year compared to three-year pacts O’Neill and the others previously worked under.The longer-term contracts more than halved sick days the officials receive and the amount of sick time they can buy back when they retire.The commission hopes this spring to hold an anticipated water and sewer rate increase to roughly $25 – 3 to 4 percent of the average ratepayer’s $866 annual bill.A rate hike in that range would match the current consumer price index and be significantly smaller than the 14 percent rate hike approved by the commission in 2006 and the 11 percent hike approved last year.The combined water and sewer rate, or the amount the commission charges per 100 cubic feet of water use, has climbed from $2.58 in 1987 to $5.10 in 1997 with rate hikes remaining under 5 percent annually between 1997 and 2004.Lynn’s combined rate is relatively low compared to many northeastern Massachusetts communities like Nahant and Swampscott that had combined rates of over $1,000 apiece three years ago.