The House put a hold on water projects money in a spending bill yesterday after several lawmakers warned that approval would take the steam out of reform legislation designed to force more cost-sharing from local governments.

The vote was 258 to 170 to freeze $48 million for 41 water projects in the end-of-the-fiscal-year spending measure.

The House then approved, 320 to 106, the overall spending bill, which includes $27 million in nonmilitary aid to Nicaraguan rebels sought by the Reagan administration.

The measure was negotiated by House and Senate conferees and must be approved by the full Senate before it goes to President Reagan for his signature. If the Senate does not accept the House action, the conferees will have to reconvene and the bill could be delayed.

The House vote on the water projects vacated an agreement forged last week stipulating that the money would be released only if cost-sharing arrangements were worked out on each project with the Army Corps of Engineers or Congress approved cost-sharing legislation, which is pending in both chambers.

Under law, the government pays most of the cost of water projects, an arrangement that environmentalists and the White House say discourages localities from selecting among projects and creates a huge and costly pork barrel for Congress.

Opponents of the water projects money said that while the supplemental spending bill embodied the concept of cost-sharing, it contained 21 projects that had never been authorized by the House Public Works and Transportation Committee.

In addition, many projects were located in the congressional districts of members of the House and Senate Appropriations committees, which put together the spending bill. And the cost-sharing agreement specifically exempted projects along the Mississippi River and its tributaries, which are the special province of House Appropriations Committee Chairman Jamie L. Whitten (D-Miss.).

Public Works committee members said the list of projects in the supplemental spending measure was skewed toward a handful of states and lawmakers. They said their panel has approved an omnibus water bill with cost-sharing formulas and a more regionally balanced group of about 200 water projects. Funding 41 water projects now, they said, would relieve the pressure to pass that bill.